Avinger (AVGR) 10-Q 7 Nov 24 2024 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2024	Nov. 04, 2024
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2024
Document Transition Report	false
Entity File Number	001-36817
Entity Registrant Name	AVINGER, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-8873453
Entity Address, Address Line One	400 Chesapeake Drive
Entity Address, City or Town	Redwood City
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94063
City Area Code	650
Local Phone Number	241-7900
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	AVGR
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		3,196,791
Entity Central Index Key	0001506928
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Amendment Flag	false

Condensed Balance Sheets (Curre

Condensed Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 5,901	$ 5,275
Accounts receivable, net of allowance for doubtful accounts of $56 and $41 at September 30, 2024 and December 31, 2023, respectively	877	1,014
Inventories, net	3,759	5,298
Prepaid expenses and other current assets	947	575
Total current assets	11,484	12,162
Right of use asset	1,427	1,102
Property and equipment, net	466	487
Other assets	224	19
Total assets	13,601	13,770
Current liabilities:
Accounts payable	921	777
Accrued compensation	1,962	2,311
Preferred stock dividends payable	653	0
Accrued expenses and other current liabilities	589	817
Leasehold liability, current portion	1,210	1,102
Borrowings	4,168	14,293
Total current liabilities	9,503	19,300
Leasehold liability, long-term portion	217	0
Other long-term liabilities	6	672
Total liabilities	9,726	19,972
Commitments and contingencies (Note 6)
Stockholders’ equity (deficit):
Preferred stock issuable in series, par value of $0.001; Shares authorized: 5,000,000 at September 30, 2024 and December 31, 2023; Shares issued and outstanding: 30,229 and 62,881 at September 30, 2024 and December 31, 2023, respectively; aggregate liquidation preference of $18,338 and $62,796 at September 30, 2024 and December 31, 2023, respectively	0	0
Common stock, par value of $0.001; Shares authorized: 100,000,000 at September 30, 2024 and December 31, 2023; Shares issued and outstanding: 2,783,891 and 1,279,928 at September 30, 2024 and December 31, 2023, respectively	3	1
Additional paid-in capital	438,153	414,493
Accumulated deficit	(434,281)	(420,696)
Total stockholders’ equity (deficit)	3,875	(6,202)
Total liabilities and stockholders’ equity (deficit)	$ 13,601	$ 13,770

Condensed Balance Sheets (Cur_2

Condensed Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Accounts Receivable, Allowance for Credit Loss, Current	$ 56	$ 41
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Preferred Stock, Shares Authorized (in shares)	5,000,000	5,000,000
Preferred Stock, Shares Issued (in shares)	30,229	62,881
Preferred Stock, Shares Outstanding (in shares)	30,229	62,881
Preferred Stock, Liquidation Preference, Value	$ 18,338	$ 62,796
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001	$ 0.001
Common Stock, Shares Authorized (in shares)	100,000,000	100,000,000
Common Stock, Shares, Issued (in shares)	2,783,891	1,279,928
Common Stock, Shares, Outstanding (in shares)	2,783,891	1,279,928

Condensed Statements of Operati

Condensed Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenues	$ 1,650	$ 1,817	$ 5,356	$ 5,746
Cost of revenues	1,224	1,429	4,209	4,117
Gross profit	426	388	1,147	1,629
Operating expenses:
Research and development	1,086	1,044	3,052	3,388
Selling, general and administrative	3,009	3,377	10,980	10,261
Total operating expenses	4,095	4,421	14,032	13,649
Loss from operations	(3,669)	(4,033)	(12,885)	(12,020)
Interest expense, net	(48)	(455)	(698)	(1,292)
Other income (expense), net	11	12	(2)	16
Net loss and comprehensive loss	(3,706)	(4,476)	(13,585)	(13,296)
Accretion of preferred stock dividends	(349)	2,436	(652)	0
Gain on exchange of Series A for Series A-1 convertible preferred stock	0	0	1,908	0
Net loss applicable to common stockholders	$ (4,055)	$ (2,040)	$ (12,329)	$ (13,296)
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (1.82)	$ (2.92)	$ (6.93)	$ (21.48)
Weighted average common shares used to compute net loss per share, basic and diluted (in shares)	2,224	698	1,780	619

Condensed Statements of Stockho

Condensed Statements of Stockholders' Equity (Deficit) (Unaudited) - USD ($) $ in Thousands	Preferred Stock [Member] Private Placement [Member]	Preferred Stock [Member] Series A-1 Preferred Stock [Member]	Preferred Stock [Member]	Common Stock [Member] Private Placement [Member]	Common Stock [Member]	Additional Paid-in Capital [Member] Private Placement [Member]	Additional Paid-in Capital [Member] Series A-1 Preferred Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member] Private Placement [Member]	Retained Earnings [Member] Series A-1 Preferred Stock [Member]	Retained Earnings [Member]	Private Placement [Member]	Series A-1 Preferred Stock [Member]	Total
Balance (in shares) at Dec. 31, 2022			60,961		522,177
Balance at Dec. 31, 2022			$ 0		$ 8			$ 406,514			$ (402,376)			$ 4,146
Issuance of common stock in public offerings, net of commissions and issuance costs (in shares)			0		607,236
Issuance of common stock in public offerings, net of commissions and issuance costs			$ 0		$ 1			5,173			0			5,174
Conversion of CRG loan principal into Series E convertible preferred stock (in shares)			1,920		0
Conversion of CRG loan principal into Series E convertible preferred stock			$ 0		$ 0			1,920			0			1,920
Employee stock-based compensation			$ 0		$ 0			703			0			703
Reclassifications and adjustments due to rounding impact from reverse stock split for fractional shares (in shares)			0		56,896
Reclassifications and adjustments due to rounding impact from reverse stock split for fractional shares			$ 0		$ (9)			9			0			0
Net and comprehensive loss											(13,296)			(13,296)
Exercises of pre-funded warrants for common stock (in shares)			0		91,325
Exercises of pre-funded warrants for common stock			$ 0		$ 1			(2)			0			(1)
Issuance of common stock upon vesting of restricted stock units (in shares)			0		2,294
Issuance of common stock upon vesting of restricted stock units			$ 0		$ 0			0			0			0
Net Income (Loss) Attributable to Parent											(13,296)			(13,296)
Balance (in shares) at Sep. 30, 2023			62,881		1,279,928
Balance at Sep. 30, 2023			$ 0		$ 1			414,317			(415,672)			(1,354)
Balance (in shares) at Dec. 31, 2022			60,961		522,177
Balance at Dec. 31, 2022			$ 0		$ 8			406,514			(402,376)			4,146
Balance (in shares) at Dec. 31, 2023			62,881		1,279,928
Balance at Dec. 31, 2023			$ 0		$ 1			414,493			(420,696)			(6,202)
Balance (in shares) at Jun. 30, 2023			60,961		622,578
Balance at Jun. 30, 2023			$ 0		$ 9			404,597			(411,196)			(6,590)
Issuance of common stock in public offerings, net of commissions and issuance costs (in shares)			0		600,454
Issuance of common stock in public offerings, net of commissions and issuance costs			$ 0		$ 1			5,136			0			5,137
Conversion of CRG loan principal into Series E convertible preferred stock (in shares)			1,920		0
Conversion of CRG loan principal into Series E convertible preferred stock			$ 0		$ 0			1,920			0			1,920
Employee stock-based compensation			$ 0		$ 0			219			0			219
Reclassifications and adjustments due to rounding impact from reverse stock split for fractional shares (in shares)			0		56,896
Reclassifications and adjustments due to rounding impact from reverse stock split for fractional shares			$ 0		$ (9)			9			0			0
Waiver of Series A preferred stock dividends			0		0			2,436			0			2,436
Net and comprehensive loss			0		0			0			(4,476)			(4,476)
Net Income (Loss) Attributable to Parent			$ 0		$ 0			0			(4,476)			(4,476)
Balance (in shares) at Sep. 30, 2023			62,881		1,279,928
Balance at Sep. 30, 2023			$ 0		$ 1			414,317			(415,672)			(1,354)
Balance (in shares) at Dec. 31, 2023			62,881		1,279,928
Balance at Dec. 31, 2023			$ 0		$ 1			414,493			(420,696)			(6,202)
Issuance of common stock in public offerings, net of commissions and issuance costs (in shares)	7,224	10,000	0	75,327	330,000
Issuance of common stock in public offerings, net of commissions and issuance costs	$ 0	$ 0	$ 0	$ 0	$ 0	$ 6,880	$ 0	5,155	$ 0	$ 0	0	$ 6,880	$ 0	5,155
Conversion of CRG loan principal into Series E convertible preferred stock (in shares)			11,000		0
Conversion of CRG loan principal into Series E convertible preferred stock			$ 0		$ 0			11,000			0			11,000
Employee stock-based compensation			0		0			1,525			0			1,525
Net and comprehensive loss			$ 0		$ 0			0			(13,585)			(13,585)
Exercises of pre-funded warrants for common stock (in shares)			0		867,457
Exercises of pre-funded warrants for common stock			$ 0		$ 1			0			0			1
Accretion of preferred stock dividends			0		0			(652)			0			(652)
Net Income (Loss) Attributable to Parent			$ 0		$ 0			0			(13,585)			(13,585)
Issuance of common stock warrants in connection with the Private Placement (in shares)			0		0
Issuance of common stock warrants in connection with the Private Placement			$ 0		$ 0			127			0			127
Issuance of common stock warrants in connection with the Private Placement			$ 0		$ 0			127			0			127
Cancellation of Series A preferred stock (in shares)			(60,876)		0
Cancellation of Series A preferred stock			$ 0		$ 0			0			0			0
Issuance of common stock upon vesting of restricted stock awards (in shares)			0		368,503
Issuance of common stock upon vesting of restricted stock awards			$ 0		$ 1			0			0			1
Net share settlement of restricted stock awards in satisfaction of tax obligations (in shares)			0		(137,324)
Net share settlement of restricted stock awards in satisfaction of tax obligations			$ 0		$ 0			(374)			0			(374)
Balance (in shares) at Sep. 30, 2024			30,229		2,783,891
Balance at Sep. 30, 2024			$ 0		$ 3			438,153			(434,281)			3,875
Balance (in shares) at Jun. 30, 2024			30,229		1,916,434
Balance at Jun. 30, 2024			$ 0		$ 2			438,326			(430,575)			7,753
Conversion of CRG loan principal into Series E convertible preferred stock (in shares)			0		0
Conversion of CRG loan principal into Series E convertible preferred stock			$ 0		$ 0			0			0			0
Employee stock-based compensation			0		0			222			0			222
Net and comprehensive loss			0		0			0			(3,706)			(3,706)
Issuance of common stock in public offerings, net of commissions and issuance costs			$ 0		$ 0			(45)			0			(45)
Exercises of pre-funded warrants for common stock (in shares)			0		867,457
Exercises of pre-funded warrants for common stock			$ 0		$ 1			0			0			1
Accretion of preferred stock dividends			0		0			(349)			0			(349)
Net Income (Loss) Attributable to Parent			$ 0		$ 0			0			(3,706)			(3,706)
Balance (in shares) at Sep. 30, 2024			30,229		2,783,891
Balance at Sep. 30, 2024			$ 0		$ 3			$ 438,153			$ (434,281)			$ 3,875

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Cash flows from operating activities
Net Income (Loss) Attributable to Parent	$ (13,585)	$ (13,296)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	245	214
Amortization of debt issuance costs and debt discount	32	62
Stock-based compensation	1,525	703
Noncash interest expense and other charges	844	1,488
Change in right of use asset	16	42
Provision for excess and obsolete inventories	111	350
Other non-cash charges	14	(51)
Changes in operating assets and liabilities:
Accounts receivable	122	278
Inventories	1,205	(996)
Prepaid expenses and other current assets	(372)	(188)
Other assets	(221)	21
Accounts payable	144	(82)
Accrued compensation	(349)	(250)
Accrued expenses and other current liabilities	(228)	240
Other long-term liabilities	(666)	422
Net cash used in operating activities	(11,163)	(11,043)
Cash flows from investing activities
Purchase of property and equipment	0	(8)
Net cash used in investing activities	0	(8)
Cash flows from financing activities
Proceeds from issuance of common stock upon warrant exercises	1	0
Net share settlement on restricted stock awards in satisfaction of tax obligations	(374)	0
Net cash provided by financing activities	11,789	5,173
Net change in cash and cash equivalents	626	(5,878)
Cash and cash equivalents, beginning of period	5,275	14,603
Cash and cash equivalents, end of period	5,901	8,725
Supplemental disclosure of cash flow information
Increase to right of use asset and leasehold liability arising from lease amendment	1,177	0
Conversion of CRG loan principal and accrued interest into Series H convertible preferred stock	11,000	1,920
Accretion of preferred stock dividends	652	0
Reclassification of other long-term liabilities to accrued compensation	0	796
Transfers between inventory and property and equipment	223	32
Private Placement [Member]
Cash flows from financing activities
Proceeds from the issuance of common stock and convertible preferred stock in a private placement, net of commissions and issuance costs	7,007	0
Public Offering [Member]
Cash flows from financing activities
Proceeds from the issuance of common stock and convertible preferred stock in a private placement, net of commissions and issuance costs	$ 5,155	$ 5,173

Note 1 - Organization

Note 1 - Organization	9 Months Ended
	Sep. 30, 2024
Notes to Financial Statements
Nature of Operations [Text Block]	1. Organization Organization, Nature of Business Avinger, Inc. (the “Company”), a Delaware corporation, was incorporated in March 2007. The Company designs, manufactures and sells image-guided, catheter-based systems that are used by physicians to treat patients with peripheral artery disease (“PAD”). Patients with PAD have a build-up of plaque in the arteries that supply blood to areas away from the heart, particularly the pelvis and legs. The Company manufactures and sells a suite of products in the United States (“U.S.”) and in select international markets. The Company has developed its Lumivascular platform, which integrates optical coherence tomography (“OCT”) visualization with interventional catheters and is the industry’s only system that provides real-time intravascular imaging during the treatment portion of PAD procedures. The Company’s Lumivascular platform consists of a capital component, Lightbox consoles, as well as a variety of disposable catheter products. The Company’s current catheter products include Ocelot, Tigereye and Tigereye ST, which are designed to allow physicians to penetrate a total blockage in an artery, known as a chronic total occlusion (“CTO”). The Company also has image-guided atherectomy products, Pantheris, Pantheris SV and Pantheris LV, which are designed to allow physicians to precisely remove arterial plaque in PAD patients. The Company is in the process of developing next-generation CTO crossing devices to target coronary CTO markets. The Company is located in Redwood City, California. Liquidity Matters The accompanying financial statements have been prepared assuming that the Company will continue as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business. The Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) No. 2014-15, Presentation of Financial Statements - Going Concern (Subtopic 205-40) In the course of its activities, the Company has incurred losses and negative cash flows from operations since its inception. As of September 30, 2024, the Company had an accumulated deficit of $434.3 million. The Company expects to incur losses for the foreseeable future. The Company believes that its cash and cash equivalents of $5.9 million at September 30, 2024, together with debt and other financing activities and expected revenues from operations will be sufficient to allow the Company to fund its current operations through the end of the fourth quarter of 2024. On March 5, 2024, the Company entered into a financing as part of a broader strategic collaboration with Zylox-Tonbridge Medical Technology Co., Ltd. (“Zylox-Tonbridge”) in which the Company received an aggregate of $7.5 million before any commissions, legal and accounting fees, and other ancillary expenses as described more fully below. On June 17, 2024, the Company completed a public offering in which it received an aggregate of $6.0 million before any commissions, legal and accounting fees, and other ancillary expenses. The Company had also received net proceeds of approximately $6.5 million from the sale of its common stock under an At The Market Offering Agreement from the time of activation through the quarter ended September 30, 2024. On October 17, 2024, the Company reactivated the ATM Agreement. During October and part of November 2024, the Company sold 107,080 shares of common stock pursuant to the ATM Agreement at an average price of $0.82 per share for aggregate proceeds of approximately $88,000, of which approximately $2,600 was paid in the form of commissions to the Agent. The Company may seek to raise additional funds in future equity offerings to meet its operational needs and capital requirements for product development, clinical trials and commercialization or other strategic objectives. The Company can provide no assurance that it will be successful in raising funds pursuant to additional equity or debt financings or that such funds will be raised at prices that do not create substantial dilution for its existing stockholders. Given the volatility in the Company’s stock price, any financing that the Company may undertake in the next twelve months could cause substantial dilution to its existing stockholders, and there can be no assurance that the Company will be successful in acquiring additional funding at levels sufficient to fund its various endeavors. These conditions raise substantial doubt about the Company’s ability to continue as a going concern. In addition, the macroeconomic environment has in the past resulted in and could continue to result in reduced consumer and investor confidence, instability in the credit and financial markets, volatile corporate profits and reduced business and consumer spending, which could increase the cost of capital and/or limit the availability of capital to the Company. If the Company is unable to raise additional capital in sufficient amounts or on terms acceptable to it, the Company may have to significantly reduce its operations or delay, scale back or discontinue the development and sale of one or more of its products. The financial statements do not include any adjustments that might result from the outcome of this uncertainty. The Company’s ultimate success will largely depend on its continued development of innovative medical technologies, its ability to successfully commercialize its products and its ability to raise significant additional funding. Additionally, due to the substantial doubt about the Company’s ability to continue operating as a going concern and the “Material Adverse Change” clause in the Loan Agreement with CRG Partners III L.P. and certain of its affiliated funds (collectively “CRG”), the entire amount of outstanding borrowings at September 30, 2024 and December 31, 2023 has been classified as current in these financial statements. CRG has not purported that an Event of Default (as defined in the Loan Agreement) has occurred due to a Material Adverse Change. Currently substantially all of the Company’s cash and cash equivalents are held at a single financial institution. The Company’s previous banking partner was acquired by another financial institution in 2023 following closure by state regulators. The Company has regained access to its accounts with the new institution and is currently reviewing its banking relationships. Potential future disruptions to financial institutions where the Company holds accounts or has credit arrangements, or more widespread disruptions in the financial services industry, could negatively impact the Company’s access to cash and cash equivalents. If the Company is unable to access its cash and cash equivalents as needed, its financial position and ability to operate its business will be adversely affected. Public Offerings June 2024 Offering On June 13, 2024, the Company entered into a securities purchase agreement with two institutional investors for the issuance and sale of 3,614,457 shares of its common stock in a best efforts public offering (“the Offering”) at a purchase price of $1.66 per share, or pre-funded warrants in lieu thereof. The Company received aggregate net proceeds of approximately $5.2 million after underwriting discounts, commissions, legal and accounting fees, and other ancillary expenses. As a result, the Company issued (i) 330,000 shares of common stock, (ii) and pre-funded warrants in lieu of common stock to purchase up to an aggregate of 3,284,457 shares of common stock (the “Pre-Funded Warrants”). During the third quarter of 2024, a total of 867,457 shares of the Pre-Funded Warrants were exercised resulting in the issuance of an aggregate of 867,457 shares of common stock. After giving effect to these aforementioned exercises, as of September 30, 2024, 2,417,000 Pre-Funded Warrants remain outstanding. In addition, the Company issued to the investors in the Offering (i) Series A-1 warrants (the “Series A-1 Warrants”) to purchase up to an aggregate of 3,614,457 shares of common stock, (ii) Series A-2 warrants (the “Series A-2 Warrants”) to purchase up to an aggregate of 3,614,457 shares of common stock, and (iii) Series A-3 warrants (the “Series A-3 Warrants,” and together with the Series A-1 Warrants and Series A-2 Warrants, the “Warrants”) to purchase up to an aggregate of 3,614,457 shares of common stock. Each share of common stock or Pre-Funded Warrant was sold together with one one one one one one The Series A-1 Warrants expire on the earlier of August 12, 2029 and 60 days following the public announcement by the Company of the Company receiving FDA clearance of second image-guided coronary device with a therapeutic indication other than diagnostic imaging or coronary CTO crossing. The Series A-2 Warrants expire on the earlier of August 12, 2026 60 days following the date of the public announcement by the Company of the occurrence of the Company receiving 510(k) clearance of image-guided Coronary CTO crossing device. The Series A-3 Warrants expire on the earlier of May 12, 2025 60 days following the date of the public announcement by the Company of the occurrence of the Company receiving FDA approval of image-guided Coronary CTO investigational device exemption (“IDE”) application. Pursuant to an engagement letter (the “Engagement Letter”) with H.C. Wainwright & Co., LLC (the “Placement Agent”), the Company, in connection with the Offering, issued warrants to designees of the Placement Agent (the “Placement Agent Warrants”) to purchase up to an aggregate of 216,867 shares of common stock (the “Placement Agent Warrant Shares”). The Placement Agent Warrants have substantially the same terms as the Warrants issued and sold in the Offering, except that the Placement Agent Warrants have an exercise price of $2.075 per share and expire on June 13, 2029. At The Market Offering Agreement On May 20, 2022, the Company entered into an At The Market Offering Agreement (the “ATM Agreement”) with H.C. Wainwright & Co., LLC (the “Agent”), as sales agent, pursuant to which the Company may offer and sell shares of common stock, par value $0.001 per share (the “Shares”) up to an aggregate offering price of $7,000,000 from time to time, in an at the market public offering. Sales of the Shares are to be made at prevailing market prices at the time of sale, or as otherwise agreed with the Agent. The Agent will receive a commission from the Company of 3.0% of the gross proceeds of any Shares sold under the ATM Agreement. The Shares sold under the ATM Agreement are offered and sold pursuant to the Company’s shelf registration statement on Form S-3, which was initially filed with the SEC on March 29, 2022 and declared effective on April 7, 2022, and a prospectus supplement and the accompanying prospectus relating to the At The Market Offering filed with the SEC on May 20, 2022. On August 3, 2022, the Company suspended sales under the ATM Agreement. On March 17, 2023, the Company reactivated the ATM Agreement. During the year ended December 31, 2023, the Company sold 607,241 shares of common stock at an average price of $9.01 per share for aggregate proceeds of approximately $5.5 million, of which approximately $164,000 was paid in the form of commissions to the Agent. There were no Other than the ATM Agreement, the Company currently does not have any commitments to obtain additional funds. Strategic Partnership and Private Placement On March 4, 2024, the Company entered into a License and Distribution Agreement (the “License Agreement”) with Zylox-Tonbridge effective as of the Initial Closing (defined below), pursuant to which the Company will license and distribute certain of the Company’s products (including consumables) in the Greater China region, including mainland China, Hong Kong, Macao, and Taiwan (the “Territory”). Zylox-Tonbridge will lead all regulatory activities for the registration of the Avinger products in the Territory. Avinger will also license its intellectual property and know-how related to Avinger products to Zylox-Tonbridge so that Zylox-Tonbridge can manufacture the localized products in the Territory. Avinger will supply Avinger products to Zylox-Tonbridge until Zylox-Tonbridge’s manufacturing capability has been established and Zylox-Tonbridge has obtained the regulatory approval of the localized products manufactured by Zylox-Tonbridge. All sales of Avinger products locally manufactured by Zylox-Tonbridge with regulatory approval by the regulatory authorities in the Territory and commercialized in the Territory will be royalty bearing to Avinger at a rate from a mid-single to high-single digit percentage depending on the amount of gross revenue as defined in the License Agreement, with certain increases depending on the amount of product gross margin. The License Agreement has an initial term of 20 years, which shall be further automatically extended for additional 20-year terms, subject to certain conditions. The License Agreement may not be terminated by either party, other than for certain uncured material breaches or the other party’s insolvency. During the three and nine months ended September 30, 2024, the Company received approximately $0.2 million and $0.4 million respectively from Zylox-Tonbridge related to inventory consumed for regulatory approval which is recorded as a reduction to research and development expenses in the Condensed Statement of Operations and Comprehensive Loss for the three months ended September 30, 2024 which substantially offset the related expenditures associated with the inventory consumption. In connection with the License Agreement, on March 4, 2024, the Company and Zylox-Tonbridge also entered into a Strategic Cooperation and Framework Agreement in conjunction with the Initial Closing (the “Collaboration Agreement” and, together with the License Agreement, the “Strategic Collaboration”), which provides the opportunity for the Company to access certain Zylox-Tonbridge peripheral vascular products for distribution in the U.S. and Germany. The agreement also provides the option for Avinger to source finished goods inventory from Zylox-Tonbridge following registration of Zylox-Tonbridge’s manufacturing facility with the FDA. Private Placement On March 4, 2024, in connection with the Strategic Collaboration, the Company and Zylox-Tonbridge Medical Limited, a wholly-owned subsidiary of Zylox-Tonbridge (the “Purchaser”), entered into a Securities Purchase Agreement (the “Purchase Agreement”), pursuant to which the Purchaser agreed to purchase, in two tranches, up to an aggregate of $15 million in shares of the Company’s common stock, and shares of two new series of the Company’s preferred stock (the “Private Placement”). On March 5, 2024, (the “Initial Closing”), the Company issued to the Purchaser 75,327 shares of the common stock at a purchase price per share of $3.664 (the “Purchase Price”), and 7,224 shares of a newly authorized Series F convertible preferred stock, par value $0.001 per share (the “Series F Preferred Stock”), at a purchase price per share of $1,000, for an aggregate purchase price of $7.5 million. Each share of Series F Preferred Stock has a stated value of $1,000 and is initially convertible into approximately 273 shares of common stock at a conversion price equal to the Purchase Price, subject to the terms of the Certificate of Designation of Preferences, Rights, and Limitations of the Series F Preferred Stock (the “Series F Certificate of Designation”). Upon completion of the following as mutually agreed upon by the Company and the Purchaser: (i) the successful registration and listing under 21 CFR part 807 with the FDA of the Purchaser and one of its designated affiliates to manufacture Avinger’s products, and (ii) the Company achieving an aggregate of $10 million in gross revenue within any four consecutive fiscal quarters after the Initial Closing, excluding any gross revenue achieved by Avinger under the License Agreement discussed above (together, the “Milestones”), the Purchaser will invest an additional $7.5 million (the “Milestone Closing”) to purchase shares of the Company’s new Series G convertible preferred stock, par value $0.001 per share (the “Series G Preferred Stock”). Each share of Series G Preferred Stock will have a stated value of $1,000 and will be convertible into shares of common stock at a conversion price of equal to the lowest of (x) the Purchase Price, (y) the closing price of the common stock on the date immediately preceding the Milestone Closing, and (z) the average closing price for the last five trading days preceding the Milestone Closing, provided that the conversion price will be no less than $0.20. The Milestone Closing was determined to be a separate freestanding equity-classified instrument issued together with the common stock and Series F preferred stock, all of which are classified within equity. On May 22, 2024, the Company held a special meeting of stockholders to vote on the following proposals resulting from the Private Placement (i) accept conversion of the shares of Series F Preferred Stock in excess of 19.9% of the Company’s outstanding common stock, which may be deemed a “change of control” under Nasdaq Listing Rule 5635(b) and (ii) issue and sell shares of Series G Preferred Stock upon completion of the Milestones. Both proposals were approved by the Company’s stockholders. There were no conversions of Series F Preferred Stock during the three months ended September 30, 2024. The Company engaged two financial advisors in connection with the Private Placement and agreed to pay them an aggregate cash fee equal to 7% of the gross proceeds to the Company. Additionally, the Company agreed to issue to one financial advisor warrants to purchase an aggregate number of shares of common Stock equal to 2% of the gross proceeds. In connection with the Private Placement, the Company issued the financial advisor warrants (the “Advisor Warrants”) to purchase 40,938 shares of common stock. The cash fee of approximately $0.5 million and warrants with a fair value of approximately $0.1 million are considered financing costs and are recognized as a reduction of the proceeds from the Private Placement. Series A Preferred Stock Exchange On March 5, 2024, the Company entered into a Securities Purchase Agreement (the “A-1 Securities Purchase Agreement”) with CRG to exchange all outstanding shares of Series A preferred stock for 10,000 shares of Series A-1 preferred stock (the “Exchange”). Among other things, the shares of Series A-1 preferred stock: (i) are convertible into an aggregate of approximately 2,729,257 shares of common stock at a conversion price equal to the Purchase Price, (ii) do not accrue or pay dividends payable solely on the Series A-1 preferred stock, (iii) will have no liquidation preference and (iv) will be junior in rank to shares of the Company’s Series E preferred stock, Series F preferred stock and Series G preferred stock. The Exchange resulted in approximately $1.9 million gain included in the net loss applicable to common holders for the nine months ended September 30, 2024. CRG Loan Amendment Also on March 5, 2024, the Company entered into Amendment No. 9 to Loan Agreement effective as of the Initial Closing (the “Amendment”) with CRG, which amends the Loan Agreement to, among other things: - extend the interest-only period through December 31, 2026; - provide that interest payable through December 31, 2026 may be payable in kind rather than in cash; and - permit the payment of dividends on the preferred stock issued or issuable to the Purchaser.

Note 2 - Summary of Significant

Note 2 - Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2024
Notes to Financial Statements
Basis of Presentation and Significant Accounting Policies [Text Block]	2. Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”) and pursuant to the rules and regulations of the SEC. The accompanying unaudited condensed interim financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the Company’s financial information. The results for the three and nine months ended September 30, 2024 are not necessarily indicative of results to be expected for the year ending December 31, 2024, or for any other interim period or for any future year. The December 31, 2023 condensed balance sheet data has been derived from audited financial statements. Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to SEC rules and regulations relating to interim financial statements. These unaudited condensed financial statements and notes should be read in conjunction with the financial statements included in the Company’s Form 10-K for the fiscal year ended December 31, 2023, which was filed with the SEC on March 20, 2024. The Company’s significant accounting policies are more fully described in Note 2 of the Notes to Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts and disclosures reported in the financial statements. Management uses significant judgment when making estimates related to its stock-based compensation, accruals related to compensation, the valuation of the common stock warrants, provisions for doubtful accounts receivable and excess and obsolete inventories, clinical trial accruals, and its reserves for sales returns and warranty costs. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions. Concentration of Credit Risk, and Other Risks and Uncertainties Financial instruments that potentially subject the Company to credit risk consist of cash and cash equivalents and accounts receivable to the extent of the amounts recorded on the balance sheets. The Company’s policy is to invest in cash and cash equivalents, consisting of money market funds. These financial instruments are held in Company accounts at one financial institution, First Citizens Bank, which acquired the Company’s prior banking partner, Silicon Valley Bank, in March 2023. The counterparties to the agreements relating to the Company’s investments consist of financial institutions of high credit standing. The Company provides for uncollectible amounts when specific credit problems arise. Management’s estimates for uncollectible amounts have been adequate, and management believes that all significant credit risks have been identified at September 30, 2024 and December 31, 2023. The Company’s previous banking partner was acquired by another financial institution in 2023 following closure by state regulators. Although the Company has regained access to its accounts with this institution, now a division of the acquiring bank, and is currently reviewing its banking relationships, potential future disruptions to financial institutions where the Company holds accounts or has credit arrangements, or more widespread disruptions in the financial services industry, could negatively impact the Company’s access to cash and cash equivalents. The Company’s accounts receivable are due from a variety of healthcare organizations in the United States and select international markets. The Company provides for uncollectible amounts when specific credit problems arise. Management’s estimates for uncollectible amounts have been adequate, and management believes that all significant credit risks have been identified at September 30, 2024 and December 31, 2023. At September 30, 2024, there was one one one two one Product Warranty Costs The Company typically offers a one Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Beginning balance $ 150 $ 128 $ 193 $ 109 Warranty provision 3 18 35 52 Usage/Release (25 ) (7 ) (100 ) (22 ) Ending balance $ 128 $ 139 $ 128 $ 139 Net Loss per Share Attributable to Common Stockholders Basic net loss per share attributable to common stockholders is computed by dividing the net loss applicable to common stockholders by the weighted average number of shares of common stock outstanding during the period, without consideration for potential dilutive common shares. Diluted net loss per share attributable to common stockholders is computed by dividing the net loss applicable to common stockholders by the weighted average number of shares of common stock and dilutive potential shares of common stock outstanding during the period. Any common stock shares subject to repurchase are excluded from the calculations as the continued vesting of such shares is contingent upon the holders’ continued service to the Company. As of September 30, 2024 and 2023, there were no Net loss per share applicable to common stockholders was determined as follows (in thousands, except per share data): Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Net loss applicable to common stockholders $ (4,055 ) $ (2,040 ) $ (12,329 ) $ (13,296 ) Weighted average common stock outstanding, basic and diluted 2,224 698 1,780 619 Net loss per share attributable to common stockholders, basic and diluted $ (1.82 ) $ (2.92 ) $ (6.93 ) $ (21.48 ) The following potentially dilutive securities outstanding have been excluded from the computations of diluted weighted average shares outstanding because such securities have an anti-dilutive impact due to losses reported: Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Common stock warrants equivalents 14,425,040 459,019 5,844,318 483,947 Common stock options 15 20 15 20 Convertible preferred stock 30,229 62,151 35,121 61,362 Unvested restricted stock units 112,459 91,630 114,730 88,585 14,567,743 612,820 5,944,184 633,914 Segment and Geographical Information The Company operates and manages its business as one Fair Value Measurements As of September 30, 2024 and December 31, 2023, cash equivalents were all categorized as Level 1 and consisted of money market funds. As of September 30, 2024 and December 31, 2023, there were no financial assets and liabilities categorized as Level 2 or 3. There were no transfers between fair value hierarchy levels during the three or nine months ended September 30, 2024 and September 30, 2023. Recent Accounting Pronouncements Recent accounting standards not yet adopted In August 2020, the FASB issued ASU No. 2020-06, Debt Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging Contracts in Entity s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity s Own Equity In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280) Improvements to Reportable Segment Disclosures In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures

Note 3 - Inventories

Note 3 - Inventories	9 Months Ended
	Sep. 30, 2024
Notes to Financial Statements
Inventory Disclosure [Text Block]	3. Inventories Inventories consisted of the following (in thousands): September 30, December 31, 2024 2023 Raw materials $ 1,863 $ 3,203 Work-in-process 154 25 Finished products 1,742 2,070 Total inventories $ 3,759 $ 5,298

Note 4 - Borrowings

Note 4 - Borrowings	9 Months Ended
	Sep. 30, 2024
Notes to Financial Statements
Debt Disclosure [Text Block]	4. Borrowings CRG On September 22, 2015, the Company entered into a Term Loan Agreement, as amended (the “Loan Agreement”) with CRG under which, subject to certain conditions, the Company had the right to borrow up to $50 million in principal amount from CRG on or before the end of the twenty-fourth (24th) month period commencing on the first Borrowing Date (as defined in the Loan Agreement). The Company borrowed $30 million on September 22, 2015. The Company borrowed an additional $10 million on June 15, 2016 under the Loan Agreement. On February 14, 2018, the Company and CRG further amended the Loan Agreement concurrent with the conversion of $38 million of the principal amount of the senior secured term loan (plus $3.8 million in back-end fees and prepayment premium applicable thereto) into a newly authorized Series A convertible preferred stock. On August 2, 2023, the Company and CRG entered into a Securities Purchase Agreement (“Series E Purchase Agreement”) pursuant to which the Company issued 1,920 shares of a newly authorized Series E convertible preferred stock (“Series E Preferred Stock”) in exchange for CRG surrendering for cancellation $1.92 million of outstanding principal and accrued interest of the senior secured term loan under the Loan Agreement. Each share of Series E preferred stock has a stated value of $1,000 per share and is convertible into 93 shares of the Company’s common stock at a conversion price of $10.725 per share. On May 16, 2024, the Company and CRG entered into another Securities Purchase Agreement (“Series H Purchase Agreement”) pursuant to which the Company issued 11,000 shares of a newly authorized Series H convertible preferred stock (“Series H Preferred Stock”) in exchange for CRG surrendering for cancellation $11.0 million of outstanding principal and accrued interest of the senior secured term loan under the Loan Agreement. Each share of Series H preferred stock has a stated value of $1,000 per share and is convertible into 259 shares of the Company’s common stock at a conversion price of $3.86 per share. Both the shares of Series E preferred stock and Series H preferred stock cannot be converted into common stock to the extent the applicable holder would beneficially own in excess 9.99% of the Company’s outstanding voting power and in no case will the beneficial ownership limitation exceed 19.99% of the Company’s outstanding voting power on a combined basis (as CRG collectively holds all of the issued and outstanding shares of the Company’s Series A-1 Convertible Preferred Stock, Series E Convertible Preferred Stock and Series H Convertible Preferred Stock), unless approved by the Company's stockholders in accordance with Nasdaq Listing Rule 5635(b). The Company has entered into several amendments to the Loan Agreement (the “Amendments”) with CRG since September 2015. The Amendments, among other things: (1) extended the interest-only period through December 31, 2026; (2) extended the period during which the Company may elect to pay a portion of interest in payment-in-kind (“PIK”), interest payments through December 31, 2026 so long as no Default (as defined in the Loan Agreement) has occurred and is continuing; (3) permitted the Company to make the entire interest payments in PIK interest payments through December 31, 2026 so long as no Default has occurred and is continuing; (4) extended the Stated Maturity Date (as defined in the Loan Agreement) to December 31, 2028; (5) reduced the minimum liquidity covenant to $3.5 million at all times; (6) eliminated the minimum revenue covenants for all years (7) changed the date under the on-going stand-alone representation regarding no “Material Adverse Change” to December 31, 2020; (8) amended the on-going stand-alone representation and stand-alone Event of Default (as defined in the Loan Agreement) regarding Material Adverse Change such that any adverse change in or effect upon the revenue of the Company and its subsidiaries due to the outbreak of COVID-19 will not constitute a Material Adverse Change; (9) provided CRG with board observer rights and (10) provide that the board observer may be appointed or removed by written notice from the Majority Lenders (as defined in the Loan Agreement). On January 26, 2024, the Company entered into Amendment No. 8 to the Loan Agreement with CRG, which reduced the minimum liquidity requirement of the Loan Agreement from $3.5 million to $1.0 million until April 1, 2024. Thereafter, the Company was subject to the minimum liquidity requirement of $3.5 million. On March 5, 2024, the Company entered into Amendment No. 9 to the Loan Agreement with CRG, which (1) extended the interest-only period through December 31, 2026; (2) extended the period during which the Company may elect to pay a portion of interest in PIK interest payments through December 31, 2026 so long as no Default (as defined in the Loan Agreement) has occurred and is continuing; (3) permitted the Company to make the entire interest payments in PIK interest payments through December 31, 2026 so long as no Default has occurred and is continuing; and (4) permit the payment of dividends on the preferred stock issued or issuable to the Purchaser. The Company assessed Amendment No. 9 to the Loan Agreement and determined that this represented a loan modification. As such, the unamortized portion of previous issuance costs incurred will be amortized over the modified term, and costs incurred with third parties was expensed as incurred. On June 5, 2024, the Company entered into Amendment No. 10 to the Loan Agreement with CRG, which reduced the minimum liquidity requirement of the Loan Agreement from $3.5 million to $1.5 million for the period commencing June 1, 2024 and ending July 31, 2024. Thereafter, the Company will be subject to the minimum liquidity requirement of $3.5 million. Under the amended Loan Agreement, no cash payments for either principal or interest are required until the first quarter of 2027. The interest will be accrued and included in the debt balance based (to the extent not paid) on principal amounts outstanding at the beginning of the quarter at an interest rate of 12.5%. Beginning in the first quarter of 2027, the Company will be required to make quarterly principal payments (in addition to the interest) of $0.5 million with total principal payments of $1.8 million in 2027 and $1.8 million in 2028. Total cash interest payments required to be made are $0.4 million and $0.1 million for 2027 and 2028 respectively. The maturity date of the Loan (as defined in the Loan Agreement) is December 31, 2028. The Company may voluntarily prepay the borrowings in full, with a prepayment premium beginning at 5.0% and declining by 1.0% annually thereafter, with no premium being payable if prepayment occurs after seven and half years of the loan. There is currently no prepayment premium payable. Each tranche of borrowing required the payment, on the borrowing date, of a financing fee equal to 1.5% of the borrowed loan principal, which is recorded as a discount to the debt. In addition, a facility fee equal to 15.0% of the amounts borrowed plus any PIK is to be payable at the end of the term or when the borrowings are repaid in full. A short-term liability is being accreted using the effective interest method for the facility fee over the term of the Loan Agreement with a corresponding discount to the debt. The borrowings are collateralized by a security interest in substantially all of the Company’s assets. The Loan Agreement requires that the Company adheres to certain affirmative and negative covenants, including financial reporting requirements, certain minimum financial covenants for a pre-specified liquidity requirement and a prohibition against the incurrence of indebtedness, or creation of additional liens, other than as specifically permitted by the terms of the Loan Agreement. In particular, the covenants of the amended Loan Agreement included a covenant that the Company maintain a minimum of $3.5 million of cash and certain cash equivalents. The minimum liquidity requirement was temporarily reduced to $1.5 million until July 31, 2024. The Loan Agreement also prohibits the payment of cash dividends on the Company’s capital stock and also places restrictions on mergers, sales of assets, investments, incurrence of liens, incurrence of indebtedness and transactions with affiliates. CRG may accelerate the payment terms of the Loan Agreement upon the occurrence of certain “Events of Default” set forth therein, which include the failure of the Company to make timely payments of amounts due under the Loan Agreement, the failure of the Company to adhere to the covenants set forth in the Loan Agreement, the insolvency of the Company or upon the occurrence of a “Material Adverse Change” thereunder. As of September 30, 2024, the Company was in compliance with all applicable covenants under the Loan Agreement. As of September 30, 2024, principal, final facility fee and PIK payments under the Loan Agreement, as amended, were as follows (in thousands): Year Ending December 31, 2024 (remaining three months of the year) $ — 2025 — 2026 — 2027 2,176 2028 4,060 Total 6,236 Less: Amount of PIK additions and final facility fee to be incurred subsequent to September 30, 2024 (1,934 ) Less: Amount representing debt issuance costs (134 ) Borrowings, current portion, as of September 30, 2024 $ 4,168 In connection with drawdowns under the Loan Agreement, the Company recorded aggregate debt discounts of $1.3 million as contra-debt. The debt discounts are being amortized as non-cash interest expense using the effective interest method over the term of the Loan Agreement. As of September 30, 2024 and December 31, 2023, the balance of the aggregate debt discount was approximately $134,000 and $166,000, respectively. The Company’s interest expense associated with the amortization of debt discount was approximately $8,000 and $21,000 during the three months ended September 30, 2024 and 2023, respectively. The Company’s interest expense associated with the amortization of debt discount was approximately $32,000 and $62,000 during the nine months ended September 30, 2024 and 2023, respectively. For the three months ended September 30, 2024 and 2023, the Company incurred interest expense of approximately $116,000 and $512,000, respectively. For the nine months ended September 30, 2024 and 2023, the Company incurred interest expense of approximately $0.8 million and $1.6 million, respectively. While, as of the date hereof, CRG has not purported that an Event of Default has resulted due to a Material Adverse Change (as those terms defined in the Loan Agreement), due to the substantial doubt about the Company’s ability to continue operating as a going concern, the entire outstanding amount of borrowings under the Loan Agreement and associated aggregate debt discount at September 30, 2024 and December 31, 2023 were classified as current in these financial statements.

Note 5 - Leases

Note 5 - Leases	9 Months Ended
	Sep. 30, 2024
Notes to Financial Statements
Lessee, Operating Leases [Text Block]	5. Leases The Company’s operating lease obligations primarily consist of leased office, laboratory, and manufacturing space under a non-cancelable operating lease. In addition to the minimum future lease commitments presented below, the lease requires the Company to pay property taxes, insurance, maintenance, and repair costs. The most recent amendment also provides an optional one The current lease was to expire on November 30, 2024. On March 6, 2024, the Company entered into an amendment to the lease which extended the lease term for a period of one year, subsequent to the original expiration. As amended, the lease will expire on November 30, 2025. Under the terms of the amendment, the Company will be obligated to pay an additional $1.3 million in base rent payments through November 2025, beginning on December 1, 2024. In total, the Company is obligated to pay approximately $7.1 million in base rent payments through November 2025, which began on December 1, 2019. The weighted average remaining lease term as of September 30, 2024 is 1.2 years. In connection with the amendment the Company adjusted its right-of-use asset and lease liability to $2.2 million. As of the date of the amendment, the operating lease was included on the balance sheet at the present value of the future base payments discounted at a 6.5% discount rate using the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and amount equal to the lease payments in a similar economic environment as the lease does not provide an implicit rate. The Company’s operating lease expense, excluding variable maintenance fees and other expenses on a monthly basis, was approximately $105,000. Rent expense for the three months ended September 30, 2024 and 2023 was approximately $316,000 and $314,000, respectively. Rent expense for the nine months ended September 30, 2024 and 2023 was approximately $947,000 and $942,000, respectively. The Company’s variable expenses for the three months ended September 30, 2024 and 2023 were approximately $90,000 and $65,000, respectively. The Company’s variable expenses for the nine months ended September 30, 2024 and 2023 were approximately $263,000 and $233,000, respectively. Operating right-of-use asset amortization for the three months ended September 30, 2024 and 2023 was approximately $290,000 and $288,000, respectively. Operating right-of-use asset amortization for the nine months ended September 30, 2024 and 2023 was approximately $867,000 and $852,000, respectively. The following table presents the future operating lease payments and leasehold liability included on the balance sheet related to the Company’s operating lease as of September 30, 2024 (in thousands): Year Ending December 31, 2024 (remaining three months of the year) $ 313 2025 1,166 Total 1,479 Less: Imputed interest (52 ) Leasehold liability as of September 30, 2024 $ 1,427 The following table shows ROU assets and lease liabilities, and the associated financial statement line items, as of September 30, 2024 and December 31, 2023 (in thousands): Lease-Related Assets and Liabilities Financial Statement Line Items September 30, 2024 December 31, 2023 Right of use assets: Operating lease Right of use asset $ 1,427 $ 1,102 Total right of use assets $ 1,427 $ 1,102 Lease liabilities: Operating lease Leasehold liability, current portion $ 1,210 $ 1,102 Leasehold liability, long-term portion 217 — Total lease liabilities $ 1,427 $ 1,102

Note 6 - Commitments and Contin

Note 6 - Commitments and Contingencies	9 Months Ended
	Sep. 30, 2024
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	6. Commitments and Contingencies Purchase Obligations Purchase obligations consist of agreements to purchase goods and services entered into in the ordinary course of business. The Company had non-cancelable commitments to suppliers for purchases totaling approximately $0.7 million as of September 30, 2024. The majority of this amount is related to commitments to purchase inventory components and services related to the manufacturing of inventory. Legal Proceedings The Company is not currently involved in any pending legal proceedings that it believes could have a material adverse effect on our financial condition, results of operations or cash flows. From time to time, the Company may be involved in legal proceedings or investigations, which could harm our reputation, business and financial condition and divert the attention of our management from the operation of our business.

Note 7 - Stockholders' Equity

Note 7 - Stockholders' Equity	9 Months Ended
	Sep. 30, 2024
Notes to Financial Statements
Equity [Text Block]	7. Stockholders Equity Convertible Preferred Stock As of September 30, 2024 and December 31, 2023, the Company’s certificate of incorporation, as amended and restated, authorizes the Company to issue up to 5,000,000 shares of convertible preferred stock with $0.001 par value per share. As of September 30, 2024 and December 31, 2023, 30,229 and 62,881 shares, respectively, were issued and outstanding. Series A Preferred Stock Exchange On March 5, 2024, the Company entered into the A-1 Securities Purchase Agreement with CRG to exchange all 60,876 outstanding shares of Series A preferred stock for 10,000 shares of Series A-1 preferred stock. Consequently, there are no The exchange was accounted for as a capital transaction constituting an extinguishment of the Series A preferred stock through the issuance of Series A-1 preferred stock with no net impact to stockholders’ deficit. At the time of the exchange, the Series A preferred stock had approximately $1.9 million excess fair value in comparison to the Series A-1 preferred stock. The difference in fair value is treated as an adjustment to net loss applicable to common stockholders for the purpose of calculating earnings per share, see Note 2 for details. Series A-1 Convertible Preferred Stock Each share of Series A-1 preferred stock has a stated value of $1,000 per share and is convertible into 273 shares of the Company’s common stock at $3.664 per share. The Series A-1 preferred stock is convertible into a total of 2,729,257 shares of common stock subject to certain limitations contained in the A-1 Securities Purchase Agreement. Shares of Series A-1 preferred stock cannot be converted into common stock to the extent the applicable holder would beneficially own in excess of 9.99% of the Company’s outstanding voting power and in no case will the beneficial ownership limitation exceed 19.99% of the Company’s outstanding voting power, unless approved by the Company's stockholders in accordance with Nasdaq Listing Rule 5635(b).The Series A-1 preferred stock has no liquidation preference, no voting rights and ranks junior to shares of the Company’s Series E Preferred Stock, Series F Preferred Stock, Series G Preferred Stock and Series H Preferred Stock in terms of repayment and certain other rights. The Series A-1 preferred stock is immediately convertible at the option of the holder, has no stated maturity, and does not pay regularly stated dividends or interest. As of September 30, 2024, 10,000 shares of Series A-1 preferred stock were outstanding. Series B Convertible Preferred Stock The Series B preferred stock has a liquidation preference of $0.001 per share, full ratchet price based anti-dilution protection, has no voting rights and is subject to certain ownership limitations. The Series B preferred stock is immediately convertible at the option of the holder, has no stated maturity, and does not pay regularly stated dividends or interest. As of September 30, 2024 and December 31, 2023, 85 shares of Series B preferred stock remained outstanding, which are currently convertible into shares of the Company’s common stock at $1.66 per share. Series E Convertible Preferred Stock Each share of Series E preferred stock has a stated value of $1,000 per share and is convertible into 93 shares of the Company’s common stock at a conversion price of $10.725 per share. The Series E preferred stock is convertible into a total of 178,560 shares of common stock subject to certain limitations contained in the Series E Purchase Agreement. Shares of Series E preferred stock cannot be converted into common stock to the extent the applicable holder would beneficially own in excess of 9.99% of the Company’s outstanding voting power and in no case will the beneficial ownership limitation exceed 19.99% of the Company’s outstanding voting power, unless approved by the Company's stockholders in accordance with Nasdaq Listing Rule 5635(b). The holders of Series E preferred stock are entitled to receive annual accruing dividends at a rate of 8%, payable in additional shares of Series E preferred stock or cash, at the Company’s option. The shares of Series E preferred stock have full voting rights, on an as-converted basis, subject to certain limitations. The Series E preferred stock rank junior to Series H preferred stock and are senior to all other classes and series of the Company’s equity in terms of repayment and certain other rights. The Series E preferred stock accrued additional dividends of less than $0.1 million and $0.1 million during the three and nine months ended September 30, 2024, respectively, which were recognized as a reduction to additional paid-in capital in the statement of stockholders’ equity (deficit). As of September 30, 2024 and December 31, 2023, 1,920 shares of Series E preferred stock were outstanding. Series F Convertible Preferred Stock On March 4, 2024, in connection with the Purchase Agreement (see Note 1), the Company issued 7,224 shares of Series F Preferred Stock, at a purchase price per share of $1,000. Each share of Series F preferred stock is convertible into 273 shares of the Company’s common stock at a conversion price of $3.664 per share. The Series F preferred stock is convertible into a total of 1,972,152 shares of common stock subject to certain limitations contained in the Purchase Agreement. Shares of Series F preferred stock cannot be converted into common stock to the extent the applicable holder would beneficially own in excess of 49.9% of the Company’s outstanding voting power. The holders of Series F preferred stock are entitled to receive annual accruing dividends at a rate of 5% until the third anniversary of their issuance and 8% thereafter. The dividends are payable in additional shares of Series F preferred stock or cash, at the Company’s option through the third anniversary of their issuance, and at the holder’s option thereafter. The shares of Series F preferred stock have full voting rights, on an as-converted basis, subject to certain limitations. The Series F preferred stock ranks junior to Series H preferred stock, pari passu with Series E preferred stock and are senior to all other classes and series of the Company’s equity in terms of repayment and certain other rights. The Series F preferred stock accrued additional dividends of $0.1 million and $0.2 million during the three and nine months ended September 30, 2024, respectively, which were recognized as a reduction to additional paid-in capital in the statement of stockholders’ deficit. As of September 30, 2024, 7,224 shares of Series F preferred stock were outstanding. Series H Convertible Preferred Stock On May 16, 2024, in connection with the Series H Purchase Agreement (see Note 4), the Company issued 11,000 shares of Series H Preferred Stock, at a purchase price per share of $1,000. Each share of Series H preferred stock is convertible into 259 shares of the Company’s common stock at a conversion price of $3.86 per share. The Series H preferred stock is convertible into a total of 2,849,000 shares of common stock subject to certain limitations contained in the Purchase Agreement. Shares of Series H preferred stock cannot be converted into common stock to the extent the applicable holder would beneficially own in excess of 9.99% of the Company’s outstanding voting power and in no case will such beneficial ownership limitation exceed 19.99%, unless approved by the Company's stockholders in accordance with Nasdaq Listing Rule 5635(b). The holders of Series H preferred stock are entitled to receive annual accruing dividends at a rate of 8%, payable in additional shares of Series E preferred stock or cash, at the Company’s option. The shares of Series H preferred stock have full voting rights, on an as-converted basis, subject to certain limitations. The Series H preferred stock rank senior to all other classes and series of the Company’s equity in terms of repayment and certain other rights. The Series H preferred stock accrued additional dividends of $0.2 million and $0.3 million during the three and nine months ended September 30, 2024, which were recognized as a reduction to additional paid-in capital in the statement of stockholders’ deficit. As of September 30, 2024, 11,000 shares of Series H preferred stock were outstanding. Common Stock As of September 30, 2024, the Company’s certificate of incorporation, as amended and restated, authorizes the Company to issue up to 100,000,000 shares of common stock with $0.001 par value per share, of which 2,783,891 shares were issued and outstanding. March 2024 Offering On March 5, 2024, in connection with the Purchase Agreement (see Note 1), the Company issued 75,327 shares of common stock at a purchase price per share of $3.664. June 2024 Offering On June 17, 2024, in connection with the June 2024 Offering (see Note 1), the Company issued 330,000 shares of common stock at a purchase price per share of $1.66. Common Stock Warrants As of September 30, 2024, the Company had outstanding warrants to purchase common stock as follows: Total Outstanding and Exercisable Underlying Shares of Common Stock Exercise Price per Share Expiration Date Series 1 Warrants issued in the February 2018 Series B financing 8,979,000 2,993 $ 6,000.00 February 2025 Series 2 Warrants issued in the February 2018 Series B financing 8,709,500 2,903 $ 6,000.00 February 2025 Placement agent warrants issued in the January 2022 financing 1,330,000 4,433 $ 150.00 January 2027 Warrants issued in the January 2022 financing 16,150,000 53,833 $ 144.00 July 2027 Series A Preferred Investment Options issued in August 2022 financing 2,853,883 190,259 $ 22.53 February 2028 Placement agent Preferred Investment Options issued in the August 2022 financing 171,233 11,416 $ 32.85 August 2027 Advisor Warrants issued in the March 2024 financing 40,938 40,938 $ 3.664 March 2029 Pre-Funded Warrants issued in the June 2024 financing 2,417,000 2,417,000 $ 0.001 n/a Series A-1 Warrants issued in the June 2024 financing 3,614,457 3,614,457 $ 1.66 See note (1) Series A-2 Warrants issued in the June 2024 financing 3,614,457 3,614,457 $ 1.66 See note (2) Series A-3 Warrants issued in the June 2024 financing 3,614,457 3,614,457 $ 1.66 See note (3) Placement Agent Warrants issued in the June 2024 financing 216,867 216,867 $ 2.075 June 2029 Total as of September 30, 2024 51,711,792 13,784,013 (1) The Series A-1 Warrants expire on the earlier of August 12, 2029 and 60 days following the public announcement by the Company of the Company receiving FDA clearance of second image-guided coronary device with a therapeutic indication other than diagnostic imaging or coronary CTO crossing. (2) Series A-2 Warrants expire on the earlier of August 12, 2026 and 60 days following the date of the public announcement by the Company of the occurrence of the Company receiving 510(k) clearance of image-guided Coronary CTO crossing device. (3) The Series A-3 Warrants expire on the earlier of May 12, 2025 and 60 days following the date of the public announcement by the Company of the occurrence of the Company receiving FDA approval of image-guided Coronary CTO IDE application. During the three months ended September 30, 2024, a total of 867,457 Pre-Funded Warrants were exercised resulting in the issuance of an aggregate of 867,457 shares of common stock. After giving effect to these aforementioned exercises, 2,417,000 Pre-Funded Warrants remained outstanding. On October 3, 2024, holders of Pre-Funded Warrants opted to exercise a total of 306,000 shares of their warrants into common stock leaving 2,111,000 remaining. In accordance with their terms, the 2,853,833 Series B Preferred Investment Options, exercisable for 190,259 shares of common stock at an exercise price of $22.53 per share, expired on August 8, 2024. As of December 31, 2023, the Company had outstanding warrants to purchase common stock as follows: Total Outstanding and Exercisable Underlying Shares of Common Stock Exercise Price per Share Expiration Date Series 1 Warrants issued in the February 2018 Series B financing 8,979,000 2,993 $ 6,000.00 February 2025 Series 2 Warrants issued in the February 2018 Series B financing 8,709,500 2,903 $ 6,000.00 February 2025 Placement agent warrants issued in the January 2022 financing 1,330,000 4,433 $ 150.00 January 2027 Warrants issued in the January 2022 financing 16,150,000 53,833 $ 144.00 July 2027 Series A Preferred Investment Options issued in August 2022 financing 2,853,883 190,259 $ 22.53 February 2028 Series B Preferred Investment Options issued in August 2022 financing 2,853,883 190,259 $ 22.53 August 2024 Placement agent Preferred Investment Options issued in the August 2022 financing 171,233 11,416 $ 32.85 August 2027 Total as of December 31, 2023 41,047,499 456,096 March 2024 Private Placement On March 7, 2024, in connection with the closing of the Strategic Partnership and Private Placement, the Company issued Advisor Warrants at an exercise price of $3.664 per share which were immediately exercisable. The Advisor Warrants will expire five The exercise price and the number of shares of common stock issuable upon exercise of each Advisor Warrant are subject to appropriate adjustments in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting the common stock. In addition, in certain circumstances, upon a fundamental transaction, a holder of Advisor Warrants will be entitled to receive, upon exercise, the kind and amount of securities, cash or other property that such holder would have received had they exercised the Advisor Warrants prior to the fundamental transaction. The Advisor Warrants can be exercised at the option of the holders at any time after they become exercisable provided that shares cannot be exercised into common stock if the applicable holder would beneficially own in excess of 4.99% of the Company’s outstanding common stock immediately after giving effect to the exercise. A holder of the Advisor Warrants may, upon notice to the Company, increase or decrease such beneficial ownership limitation, but not in excess of 9.99%. June 2024 Offering On June 13, 2024, the Company entered into a securities purchase agreement with two institutional investors resulting in the issuance of among other things, Pre-Funded Warrants in lieu of common stock to purchase up to an aggregate of 3,284,457 shares of common stock of which 2,417,000 remain outstanding as of September 2024. The Pre-Funded Warrants have an exercise price of $0.001 per share, are immediately exercisable, and have no expiration date. On October 3, 2024, holders of Pre-Funded Warrants opted to exercise a total of 306,000 of their warrants into common stock leaving 2,111,000 remaining. In addition, the Company issued to the investors in the Offering (i) Series A-1 Warrants to purchase up to an aggregate of 3,614,457 shares of common stock, (ii) Series A-2 Warrants to purchase up to an aggregate of 3,614,457 shares of common stock, and (iii) Series A-3 Warrants to purchase up to an aggregate of 3,614,457 shares of common stock. Each share of common stock or Pre-Funded Warrant was sold together with one one one one one one The Series A-1 Warrants expire on the earlier of August 12, 2029 and 60 days following the public announcement by the Company of the Company receiving FDA clearance of second image-guided coronary device with a therapeutic indication other than diagnostic imaging or coronary CTO crossing. The Series A-2 Warrants expire on the earlier of August 12, 2026 and 60 days following the date of the public announcement by the Company of the occurrence of the Company receiving 510(k) clearance of image-guided Coronary CTO crossing device. The Series A-3 Warrants expire on May 12, 2025 and 60 days following the date of the public announcement by the Company of the occurrence of the Company receiving FDA approval of image-guided Coronary CTO IDE application. In connection with the Offering, the Company also issued to the placement agent Placement Agent or its designees Placement Agent Warrants to purchase up to an aggregate of 216,867 shares of common stock. The Placement Agent Warrants have substantially the same terms as the warrants issued and sold in the Offering, except that the Placement Agent Warrants have an exercise price of $2.075 per share and expire on June 13, 2029. The exercise price and the number of shares of common stock issuable upon exercise of each Pre-Funded Warrants, Series A-1 Warrants, Series A-2 Warrants, Series A-3 Warrants, and Placement Agent Warrants are subject to appropriate adjustments in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting the common stock. In addition, in certain circumstances, upon a fundamental transaction, a holder of Pre-Funded Warrants, Series A-1 Warrants, Series A-2 Warrants, Series A-3 Warrants, and Placement Agent Warrants will be entitled to receive, upon exercise, the kind and amount of securities, cash or other property that such holder would have received had they exercised the Pre-Funded Warrants, Series A-1 Warrants, Series A-2 Warrants, Series A-3 Warrants, and Placement Agent Warrants immediately prior to the fundamental transaction. The Pre-Funded Warrants, Series A-1 Warrants, Series A-2 Warrants, Series A-3 Warrants, and Placement Agent Warrants can be exercised at the option of the holders at any time after they become exercisable provided that shares of the Pre-Funded Warrants, Series A-1 Warrants, Series A-2 Warrants, Series A-3 Warrants, and Placement Agent Warrants cannot be exercised into common stock if the applicable holder would beneficially own in excess of 4.99% (or, upon election by such holder prior to the issuance of any shares of Pre-Funded Warrants, Series A-1 Warrants, Series A-2 Warrants, Series A-3 Warrants, and Placement Agent Warrants, 9.99%) of the Company’s outstanding common stock immediately after giving effect to the exercise. A holder of the Pre-Funded Warrants, Series A-1 Warrants, Series A-2 Warrants, Series A-3 Warrants, and Placement Agent Warrants may, upon notice to the Company, increase or decrease such beneficial ownership limitation, but not in excess of 9.99%. In the event of a fundamental transaction in which the holders of our voting securities immediately prior to such fundamental transaction will not, following such fundamental transaction, directly or indirectly own more than 50% of the voting securities of the surviving entity or successor entity, and in which the Company is not the successor entity or does not continue as a reporting issuer under the Exchange Act, then, at the request of the holder, the Company or the successor entity shall purchase the unexercised portion of the Pre-Funded Warrants, Series A-1 Warrants, Series A-2 Warrants, Series A-3 Warrants, and Placement Agent Warrants from the holder by paying to the holder an amount, in cash, equal to the fair value of the remaining unexercised portion of the Pre-Funded Warrants, Series A-1 Warrants, Series A-2 Warrants, Series A-3 Warrants, and Placement Agent Warrants on the date of such fundamental transaction, subject to certain limitations in the event of a fundamental transaction not within our control.

Note 8 - Stock-based Compensati

Note 8 - Stock-based Compensation	9 Months Ended
	Sep. 30, 2024
Notes to Financial Statements
Share-Based Payment Arrangement [Text Block]	8. Stock-Based Compensation Stock Plans In January 2015, the Board of Directors adopted and the Company’s stockholders approved the 2015 Equity Incentive Plan (“2015 Plan”). On December 22, 2023, the Company’s stockholders approved an additional 300,000 shares of common stock for issuance under the 2015 Plan, which was later registered in an S-8 registration statement filed on January 10, 2024. The 2015 Plan provides for the grant of incentive stock options (“ISOs”) to employees and for the grant of non-statutory stock options (“NSOs”), restricted stock, restricted stock awards (“RSAs”), restricted stock units (“RSUs”), stock appreciation rights, performance units and performance shares to employees, directors and consultants. As of September 30, 2024, 15 share grants were outstanding with 71,442 shares of common stock were available and outstanding for grant under the 2015 Plan. The Company’s RSUs and RSAs generally vest annually over two years in equal increments. RSAs and RSUs largely contain the same contractual terms except RSAs have the ability to vote along with common holders as an RSA is considered an outstanding security at the time of grant, subject to certain vesting and other restrictions. The Company measures the fair value of RSAs using the closing stock price of a share of the Company’s common stock on the grant date and is recognized as expense on a straight-line basis over the vesting period of the award. A summary of all RSA activity is presented below: Number of Shares Weighted Average Grant Date Fair Value Weighted Average Remaining Contractual Term Awards outstanding at December 31, 2023 90,190 $ 18.45 1.04 Awarded 394,105 $ 2.75 — Released (368,503 ) $ 4.89 — Forfeited (3,333 ) $ 18.45 — Awards outstanding at September 30, 2024 112,459 $ 7.85 0.30 As of September 30, 2024, there was $0.300 million of remaining unamortized stock-based compensation expense associated with RSAs, which will be expensed over a weighted average remaining service period of approximately 0.3 years. The outstanding non-vested and expected to vest RSAs at September 30, 2024 have an aggregate fair value of approximately $0.1 million. The Company used the closing market price of $0.95 per share at September 30, 2024, to determine the aggregate fair value for the RSAs outstanding at that date. For the nine months ended September 30, 2024 and 2023, the fair value of RSAs vested was approximately $1.0 million and less than $0.1 million, respectively. For the three months ended September 30, 2024 and 2023, stock-based compensation expense recognized associated with the vesting of RSAs was $222,000 and $219,000, respectively. For the nine months ended September 30, 2024 and 2023, stock-based compensation expense recognized associated with the vesting of RSAs was $1.5 million and $0.7 million, respectively. Total noncash stock-based compensation expense relating to the Company’s RSAs recognized, before taxes, during the three and nine months ended September 30, 2024 and 2023, is as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Cost of revenues $ 36 $ 36 $ 228 $ 99 Research and development expenses 42 24 397 158 Selling, general and administrative expenses 144 159 900 446 $ 222 $ 219 $ 1,525 $ 703

Note 9 - Restructuring Charges

Note 9 - Restructuring Charges and Expenses	9 Months Ended
	Sep. 30, 2024
Notes to Financial Statements
Restructuring and Related Activities Disclosure [Text Block]	9. Restructuring Charges and Expenses In June 2024, the Company undertook an organizational realignment and cost reduction plan which included a reduction in force, lowering its total headcount by approximately 24%, or 17 employees, compared to March 31, 2024. Accordingly, the Company recorded a restructuring charge of approximately $66,000, relating to severance related costs at that time. As of September 30, 2024, all 17 employees’ severance costs related to the June 2024 termination had been incurred and paid. As of September 30, 2024, $4,000 of the total severance costs was included within accrued compensation on the condensed balance sheet. During the three months ending September 30, 2024, the Company recorded $14,000 in severance costs related to R&D and $53,000 to SG&A. For the nine months ending September 30, 2024, an additional $23,000 in severance expenses was recorded to SG&A.

Insider Trading Arrangements

Insider Trading Arrangements	9 Months Ended
	Sep. 30, 2024
Insider Trading Arr Line Items
Material Terms of Trading Arrangement [Text Block]	ITEM 5. OTHER INFORMATION 10b5-1 Trading Plans During the second quarter of 2024, none
Rule 10b5-1 Arrangement Adopted [Flag]	false
Non-Rule 10b5-1 Arrangement Adopted [Flag]	false
Rule 10b5-1 Arrangement Terminated [Flag]	false
Non-Rule 10b5-1 Arrangement Terminated [Flag]	false

Significant Accounting Policies

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”) and pursuant to the rules and regulations of the SEC. The accompanying unaudited condensed interim financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the Company’s financial information. The results for the three and nine months ended September 30, 2024 are not necessarily indicative of results to be expected for the year ending December 31, 2024, or for any other interim period or for any future year. The December 31, 2023 condensed balance sheet data has been derived from audited financial statements. Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to SEC rules and regulations relating to interim financial statements. These unaudited condensed financial statements and notes should be read in conjunction with the financial statements included in the Company’s Form 10-K for the fiscal year ended December 31, 2023, which was filed with the SEC on March 20, 2024. The Company’s significant accounting policies are more fully described in Note 2 of the Notes to Financial Statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023.
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts and disclosures reported in the financial statements. Management uses significant judgment when making estimates related to its stock-based compensation, accruals related to compensation, the valuation of the common stock warrants, provisions for doubtful accounts receivable and excess and obsolete inventories, clinical trial accruals, and its reserves for sales returns and warranty costs. Management bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions.
Concentration of Credit Risk and Other Risks and Uncertainties [Policy Text Block]	Concentration of Credit Risk, and Other Risks and Uncertainties Financial instruments that potentially subject the Company to credit risk consist of cash and cash equivalents and accounts receivable to the extent of the amounts recorded on the balance sheets. The Company’s policy is to invest in cash and cash equivalents, consisting of money market funds. These financial instruments are held in Company accounts at one financial institution, First Citizens Bank, which acquired the Company’s prior banking partner, Silicon Valley Bank, in March 2023. The counterparties to the agreements relating to the Company’s investments consist of financial institutions of high credit standing. The Company provides for uncollectible amounts when specific credit problems arise. Management’s estimates for uncollectible amounts have been adequate, and management believes that all significant credit risks have been identified at September 30, 2024 and December 31, 2023. The Company’s previous banking partner was acquired by another financial institution in 2023 following closure by state regulators. Although the Company has regained access to its accounts with this institution, now a division of the acquiring bank, and is currently reviewing its banking relationships, potential future disruptions to financial institutions where the Company holds accounts or has credit arrangements, or more widespread disruptions in the financial services industry, could negatively impact the Company’s access to cash and cash equivalents. The Company’s accounts receivable are due from a variety of healthcare organizations in the United States and select international markets. The Company provides for uncollectible amounts when specific credit problems arise. Management’s estimates for uncollectible amounts have been adequate, and management believes that all significant credit risks have been identified at September 30, 2024 and December 31, 2023. At September 30, 2024, there was one one one two one
Standard Product Warranty, Policy [Policy Text Block]	Product Warranty Costs The Company typically offers a one Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Beginning balance $ 150 $ 128 $ 193 $ 109 Warranty provision 3 18 35 52 Usage/Release (25 ) (7 ) (100 ) (22 ) Ending balance $ 128 $ 139 $ 128 $ 139
Earnings Per Share, Policy [Policy Text Block]	Net Loss per Share Attributable to Common Stockholders Basic net loss per share attributable to common stockholders is computed by dividing the net loss applicable to common stockholders by the weighted average number of shares of common stock outstanding during the period, without consideration for potential dilutive common shares. Diluted net loss per share attributable to common stockholders is computed by dividing the net loss applicable to common stockholders by the weighted average number of shares of common stock and dilutive potential shares of common stock outstanding during the period. Any common stock shares subject to repurchase are excluded from the calculations as the continued vesting of such shares is contingent upon the holders’ continued service to the Company. As of September 30, 2024 and 2023, there were no Net loss per share applicable to common stockholders was determined as follows (in thousands, except per share data): Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Net loss applicable to common stockholders $ (4,055 ) $ (2,040 ) $ (12,329 ) $ (13,296 ) Weighted average common stock outstanding, basic and diluted 2,224 698 1,780 619 Net loss per share attributable to common stockholders, basic and diluted $ (1.82 ) $ (2.92 ) $ (6.93 ) $ (21.48 ) The following potentially dilutive securities outstanding have been excluded from the computations of diluted weighted average shares outstanding because such securities have an anti-dilutive impact due to losses reported: Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Common stock warrants equivalents 14,425,040 459,019 5,844,318 483,947 Common stock options 15 20 15 20 Convertible preferred stock 30,229 62,151 35,121 61,362 Unvested restricted stock units 112,459 91,630 114,730 88,585 14,567,743 612,820 5,944,184 633,914
Segment Reporting, Policy [Policy Text Block]	Segment and Geographical Information The Company operates and manages its business as one
Fair Value Measurement, Policy [Policy Text Block]	Fair Value Measurements As of September 30, 2024 and December 31, 2023, cash equivalents were all categorized as Level 1 and consisted of money market funds. As of September 30, 2024 and December 31, 2023, there were no financial assets and liabilities categorized as Level 2 or 3. There were no transfers between fair value hierarchy levels during the three or nine months ended September 30, 2024 and September 30, 2023.
New Accounting Pronouncements, Policy [Policy Text Block]	Recent Accounting Pronouncements Recent accounting standards not yet adopted In August 2020, the FASB issued ASU No. 2020-06, Debt Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging Contracts in Entity s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity s Own Equity In November 2023, the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280) Improvements to Reportable Segment Disclosures In December 2023, the FASB issued ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures

Note 2 - Summary of Significa_2

Note 2 - Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2024
Notes Tables
Schedule of Product Warranty Liability [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Beginning balance $ 150 $ 128 $ 193 $ 109 Warranty provision 3 18 35 52 Usage/Release (25 ) (7 ) (100 ) (22 ) Ending balance $ 128 $ 139 $ 128 $ 139
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Net loss applicable to common stockholders $ (4,055 ) $ (2,040 ) $ (12,329 ) $ (13,296 ) Weighted average common stock outstanding, basic and diluted 2,224 698 1,780 619 Net loss per share attributable to common stockholders, basic and diluted $ (1.82 ) $ (2.92 ) $ (6.93 ) $ (21.48 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Common stock warrants equivalents 14,425,040 459,019 5,844,318 483,947 Common stock options 15 20 15 20 Convertible preferred stock 30,229 62,151 35,121 61,362 Unvested restricted stock units 112,459 91,630 114,730 88,585 14,567,743 612,820 5,944,184 633,914

Note 3 - Inventories (Tables)

Note 3 - Inventories (Tables)	9 Months Ended
	Sep. 30, 2024
Notes Tables
Schedule of Inventory, Current [Table Text Block]	September 30, December 31, 2024 2023 Raw materials $ 1,863 $ 3,203 Work-in-process 154 25 Finished products 1,742 2,070 Total inventories $ 3,759 $ 5,298

Note 4 - Borrowings (Tables)

Note 4 - Borrowings (Tables)	9 Months Ended
	Sep. 30, 2024
Notes Tables
Schedule of Debt [Table Text Block]	Year Ending December 31, 2024 (remaining three months of the year) $ — 2025 — 2026 — 2027 2,176 2028 4,060 Total 6,236 Less: Amount of PIK additions and final facility fee to be incurred subsequent to September 30, 2024 (1,934 ) Less: Amount representing debt issuance costs (134 ) Borrowings, current portion, as of September 30, 2024 $ 4,168

Note 5 - Leases (Tables)

Note 5 - Leases (Tables)	9 Months Ended
	Sep. 30, 2024
Notes Tables
Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]	Year Ending December 31, 2024 (remaining three months of the year) $ 313 2025 1,166 Total 1,479 Less: Imputed interest (52 ) Leasehold liability as of September 30, 2024 $ 1,427
Right of Use Asset and Liabilities [Table Text Block]	Lease-Related Assets and Liabilities Financial Statement Line Items September 30, 2024 December 31, 2023 Right of use assets: Operating lease Right of use asset $ 1,427 $ 1,102 Total right of use assets $ 1,427 $ 1,102 Lease liabilities: Operating lease Leasehold liability, current portion $ 1,210 $ 1,102 Leasehold liability, long-term portion 217 — Total lease liabilities $ 1,427 $ 1,102

Note 7 - Stockholders' Equity (

Note 7 - Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2024
Notes Tables
Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]	Total Outstanding and Exercisable Underlying Shares of Common Stock Exercise Price per Share Expiration Date Series 1 Warrants issued in the February 2018 Series B financing 8,979,000 2,993 $ 6,000.00 February 2025 Series 2 Warrants issued in the February 2018 Series B financing 8,709,500 2,903 $ 6,000.00 February 2025 Placement agent warrants issued in the January 2022 financing 1,330,000 4,433 $ 150.00 January 2027 Warrants issued in the January 2022 financing 16,150,000 53,833 $ 144.00 July 2027 Series A Preferred Investment Options issued in August 2022 financing 2,853,883 190,259 $ 22.53 February 2028 Placement agent Preferred Investment Options issued in the August 2022 financing 171,233 11,416 $ 32.85 August 2027 Advisor Warrants issued in the March 2024 financing 40,938 40,938 $ 3.664 March 2029 Pre-Funded Warrants issued in the June 2024 financing 2,417,000 2,417,000 $ 0.001 n/a Series A-1 Warrants issued in the June 2024 financing 3,614,457 3,614,457 $ 1.66 See note (1) Series A-2 Warrants issued in the June 2024 financing 3,614,457 3,614,457 $ 1.66 See note (2) Series A-3 Warrants issued in the June 2024 financing 3,614,457 3,614,457 $ 1.66 See note (3) Placement Agent Warrants issued in the June 2024 financing 216,867 216,867 $ 2.075 June 2029 Total as of September 30, 2024 51,711,792 13,784,013 Total Outstanding and Exercisable Underlying Shares of Common Stock Exercise Price per Share Expiration Date Series 1 Warrants issued in the February 2018 Series B financing 8,979,000 2,993 $ 6,000.00 February 2025 Series 2 Warrants issued in the February 2018 Series B financing 8,709,500 2,903 $ 6,000.00 February 2025 Placement agent warrants issued in the January 2022 financing 1,330,000 4,433 $ 150.00 January 2027 Warrants issued in the January 2022 financing 16,150,000 53,833 $ 144.00 July 2027 Series A Preferred Investment Options issued in August 2022 financing 2,853,883 190,259 $ 22.53 February 2028 Series B Preferred Investment Options issued in August 2022 financing 2,853,883 190,259 $ 22.53 August 2024 Placement agent Preferred Investment Options issued in the August 2022 financing 171,233 11,416 $ 32.85 August 2027 Total as of December 31, 2023 41,047,499 456,096

Note 8 - Stock-based Compensa_2

Note 8 - Stock-based Compensation (Tables)	9 Months Ended
	Sep. 30, 2024
Notes Tables
Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block]	Number of Shares Weighted Average Grant Date Fair Value Weighted Average Remaining Contractual Term Awards outstanding at December 31, 2023 90,190 $ 18.45 1.04 Awarded 394,105 $ 2.75 — Released (368,503 ) $ 4.89 — Forfeited (3,333 ) $ 18.45 — Awards outstanding at September 30, 2024 112,459 $ 7.85 0.30
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Cost of revenues $ 36 $ 36 $ 228 $ 99 Research and development expenses 42 24 397 158 Selling, general and administrative expenses 144 159 900 446 $ 222 $ 219 $ 1,525 $ 703

Note 1 - Organization (Details

Note 1 - Organization (Details Textual)						1 Months Ended	3 Months Ended			9 Months Ended		12 Months Ended	28 Months Ended
	Oct. 03, 2024 shares	Jun. 17, 2024 USD ($) $ / shares shares	Jun. 13, 2024 USD ($) $ / shares shares	Mar. 05, 2024 USD ($) $ / shares shares	Mar. 04, 2024 USD ($) $ / shares shares	Oct. 31, 2024 USD ($) $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Jun. 13, 2024 $ / shares shares	Sep. 30, 2023 USD ($) shares	Sep. 30, 2024 USD ($) $ / shares shares	Sep. 30, 2023 USD ($) shares	Dec. 31, 2023 USD ($) $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	May 22, 2024	Dec. 23, 2023 shares	Aug. 02, 2023	May 20, 2022 USD ($) $ / shares
Retained Earnings (Accumulated Deficit) | $							$ (434,281,000)			$ (434,281,000)		$ (420,696,000)	$ (434,281,000)
Cash and Cash Equivalents, at Carrying Value | $							$ 5,901,000			$ 5,901,000		$ 5,275,000	$ 5,901,000
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) | shares							13,784,013			13,784,013			13,784,013		456,096
Class of Warrant or Right, Outstanding (in shares) | shares							51,711,792			51,711,792			51,711,792		41,047,499
Common Stock, Par or Stated Value Per Share (in dollars per share)							$ 0.001			$ 0.001		$ 0.001	$ 0.001
Preferred Stock, Par or Stated Value Per Share							$ 0.001			$ 0.001		$ 0.001	0.001
Gain (Loss) On Convertible Preferred Stock Converted to Other Securities | $							$ 0		$ 0	$ 1,908,000	$ 0
Exchange of Series A Preferred Stock Into Series A-1 Preferred Stock [Member]
Conversion of Stock, Shares Issued | shares				10,000
Gain (Loss) On Convertible Preferred Stock Converted to Other Securities | $										$ 1,900,000
Series F Preferred Stock [Member]
Stock Issued During Period, Shares, New Issues | shares					7,224
Shares Issued, Price Per Share					$ 1,000
Preferred Stock, Stated Value				$ 1,000
Preferred Stock, Convertible, Conversion Ratio				273	273
Preferred Stock, Convertible, Conversion Price (in dollars per share)					$ 3.664
Preferred Stock, Convertible, Beneficial Ownership Percentage					49.90%
Series G Preferred Stock [Member]
Preferred Stock, Stated Value					$ 1,000
Preferred Stock, Par Value					$ 0.001
Series A-1 Preferred Stock [Member]
Preferred Stock, Stated Value							$ 1,000			$ 1,000			$ 1,000
Preferred Stock, Convertible, Conversion Ratio							273			273			273
Preferred Stock, Convertible, Conversion Price (in dollars per share)							$ 3.664			$ 3.664			$ 3.664
Preferred Stock, Convertible, Beneficial Ownership Percentage																9.99%
Preferred Stock, Convertible, Shares Issuable | shares				2,729,257			2,729,257			2,729,257			2,729,257
Common Stock [Member]
Stock Issued During Period, Shares, New Issues | shares									600,454	330,000	607,236
Stock Issued During Period, Shares, Warrants Exercised (in shares) | shares							867,457			867,457	91,325
License and Distribution Agreement [Member]
License Agreement, Term					20 years
License Agreement, Renewal Term					20 years
Revenue from Collaborative Arrangement, Excluding Revenue from Contract with Customer | $							$ 200,000			$ 400,000
Pre-funded Warrants [Member]
Class of Warrant or Right, Exercised (in shares) | shares							867,457
Stock Issued During Period, Shares, Warrants Exercised (in shares) | shares							867,457
Class of Warrant or Right, Outstanding (in shares) | shares							2,417,000			2,417,000			2,417,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 0.001					$ 0.001
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 0.001					$ 0.001
Series A-1 Warrants [Member]
Number of Warrants Issued Per Unit			1					1
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right | shares			1					1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 1.66					$ 1.66
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 1.66					$ 1.66
Warrants and Rights Outstanding, Term, Period Following Public Announcement			60 days
Series A-2 Warrants [Member]
Number of Warrants Issued Per Unit			1
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right | shares			1					1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 1.66					$ 1.66
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 1.66					$ 1.66
Warrants and Rights Outstanding, Term, Period Following Public Announcement			60 days
Series A-3 Warrants [Member]
Number of Warrants Issued Per Unit			1
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right | shares			1					1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 1.66					$ 1.66
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 1.66					1.66
Warrants and Rights Outstanding, Term, Period Following Public Announcement			60 days
Placement Agent Warrants [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 2.075					2.075
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 2.075					$ 2.075
Advisor Warrants Issued In The March 2024 Financing [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) | shares				40,938			40,938			40,938			40,938
Class of Warrant or Right, Outstanding (in shares) | shares							40,938			40,938			40,938
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)							$ 3.664			$ 3.664			$ 3.664
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)							$ 3.664			$ 3.664			$ 3.664
Class of Warrant or Right, Exercise Percentage of Shares Issued in Equity Offering				2%
Maximum [Member] | Series F Preferred Stock [Member]
Preferred Stock, Convertible, Beneficial Ownership Percentage														19.90%
Maximum [Member] | Series A-1 Preferred Stock [Member]
Preferred Stock, Convertible, Beneficial Ownership Percentage							19.99%			19.99%			19.99%
Maximum [Member] | Pre-funded Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) | shares			3,284,457					3,284,457
Maximum [Member] | Series A-1 Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) | shares			3,614,457					3,614,457
Maximum [Member] | Series A-2 Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) | shares			3,614,457					3,614,457
Maximum [Member] | Series A-3 Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) | shares			3,614,457					3,614,457
Maximum [Member] | Placement Agent Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) | shares			216,867					216,867
Subsequent Event [Member] | Pre-funded Warrants [Member]
Class of Warrant or Right, Exercised (in shares) | shares	306,000
Class of Warrant or Right, Outstanding (in shares) | shares	2,111,000
Securities Purchase Agreement [Member]
Proceeds from Issuance or Sale of Equity | $				$ 7,500,000
Payments of Stock Issuance Costs | $				500,000
Agreement to Purchase Common Stock, Maximum Amount | $					$ 15,000,000
Milestone Payment, Minimum Revenue Required | $					10,000,000
Milestone Payment, Additional Authorized Amount | $					$ 7,500,000
Equity Offering, Cash Fee, Percentage of Gross Proceeds					7%
Warrants and Rights Outstanding | $				$ 100,000
Securities Purchase Agreement [Member] | Series F Preferred Stock [Member]
Stock Issued During Period, Shares, New Issues | shares				7,224
Shares Issued, Price Per Share				$ 1,000
Preferred Stock, Par or Stated Value Per Share				$ 0.001
Securities Purchase Agreement [Member] | Common Stock [Member]
Stock Issued During Period, Shares, New Issues | shares				75,327
Shares Issued, Price Per Share				$ 3.664
Securities Purchase Agreement [Member] | Minimum [Member] | Series G Preferred Stock [Member]
Preferred Stock, Convertible, Conversion Price (in dollars per share)							$ 0.2			$ 0.2			$ 0.2
Public Offering [Member]
Proceeds from Issuance or Sale of Equity | $		$ 6,000,000
The Market Offering Agreement (the “ATM Agreement”) [Member]
Proceeds from Issuance or Sale of Equity | $												$ 5,500,000
Proceeds from Issuance of Common Stock, Net | $													$ 6,500,000
Stock Issued During Period, Shares, New Issues | shares							0			0		607,241
Payments of Stock Issuance Costs | $												$ 164,000
Stock Issued During Period, Average Price Per Share												$ 9.01
The Market Offering Agreement (the “ATM Agreement”) [Member] | Subsequent Event [Member]
Proceeds from Issuance or Sale of Equity | $						$ 88,000
Stock Issued During Period, Shares, New Issues | shares						107,080
Shares Issued, Price Per Share						$ 0.82
Payments of Stock Issuance Costs | $						$ 2,600
June 2024 Offering [Member]
Stock Issued During Period, Shares, New Issues | shares		330,000	330,000
Shares Issued, Price Per Share		$ 1.66
Share Offering, Shares Issuable in Best Efforts (in shares) | shares			3,614,457					3,614,457
Share Offering, Purchase Price Per Share (in dollars per share)			$ 1.66					$ 1.66
Proceeds from Issuance or Sale of Equity, Net | $			$ 5,200,000
Common Stock in June, 2022 [Member]
Common Stock, Par or Stated Value Per Share (in dollars per share)																	$ 0.001
Share Offering Agreement, Aggregate Offering | $																	$ 7,000,000
Commission Percentage																	3%

Note 2 - Summary of Significa_3

Note 2 - Summary of Significant Accounting Policies (Details Textual) shares in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024 shares	Sep. 30, 2023 shares	Dec. 31, 2023
Warranty Period (Year)			1 year
Weighted Average Number of Shares, Common Stock Subject to Repurchase or Cancellation			0	0
Number of Reportable Segments			1
Customer Concentration Risk [Member] | Accounts Receivable [Member]
Number of Major Customers			1		1
Customer Concentration Risk [Member] | Accounts Receivable [Member] | One Customer [Member]
Concentration Risk, Percentage			38%		24%
Customer Concentration Risk [Member] | Revenue Benchmark [Member]
Number of Major Customers	2	1	1	1
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | UNITED STATES
Concentration Risk, Percentage	94%	91%	93%	92%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | One Customer [Member]
Concentration Risk, Percentage		22%	17%	17%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer, One [Member]
Concentration Risk, Percentage	20%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Customer, Two [Member]
Concentration Risk, Percentage	11%

Note 2 - Summary of Significa_4

Note 2 - Summary of Significant Accounting Policies - Product Warranty (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Beginning balance	$ 150	$ 128	$ 193	$ 109
Warranty provision	3	18	35	52
Usage/Release	(25)	(7)	(100)	(22)
Ending balance	$ 128	$ 139	$ 128	$ 139

Note 2 - Summary of Significa_5

Note 2 - Summary of Significant Accounting Policies - Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Net loss applicable to common stockholders	$ (4,055)	$ (2,040)	$ (12,329)	$ (13,296)
Weighted average common stock outstanding, basic and diluted (in shares)	2,224	698	1,780	619
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (1.82)	$ (2.92)	$ (6.93)	$ (21.48)

Note 2 - Summary of Significa_6

Note 2 - Summary of Significant Accounting Policies - Anti-dilutive Securities (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Potentially dilutive securities (in shares)	14,567,743	612,820	5,944,184	633,914
Common Stock Warrants [Member]
Potentially dilutive securities (in shares)	14,425,040	459,019	5,844,318	483,947
Common Stock Options [ member]
Potentially dilutive securities (in shares)	15	20	15	20
Preferred Stock [Member]
Potentially dilutive securities (in shares)	30,229	62,151	35,121	61,362
Restricted Stock Units (RSUs) [Member]
Potentially dilutive securities (in shares)	112,459	91,630	114,730	88,585

Note 3 - Inventories - Schedule

Note 3 - Inventories - Schedule of Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Raw materials	$ 1,863	$ 3,203
Work-in-process	154	25
Finished products	1,742	2,070
Total inventories	$ 3,759	$ 5,298

Note 4 - Borrowings (Details Te

Note 4 - Borrowings (Details Textual)						3 Months Ended		9 Months Ended
	May 16, 2024 USD ($) $ / shares shares	Aug. 02, 2023 USD ($) $ / shares shares	Aug. 10, 2022 USD ($)	Feb. 14, 2018 USD ($)	Sep. 22, 2015 USD ($)	Sep. 30, 2024 USD ($) $ / shares	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) $ / shares	Sep. 30, 2023 USD ($)	Aug. 01, 2024 USD ($)	Jul. 31, 2024 USD ($)	Jun. 05, 2024 USD ($)	Apr. 02, 2024 USD ($)	Jan. 26, 2024 USD ($)	Dec. 31, 2023 USD ($) $ / shares	Jun. 15, 2016 USD ($)
Preferred Stock, Par or Stated Value Per Share | $ / shares						$ 0.001		$ 0.001							$ 0.001
Series E Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share | $ / shares	$ 1,000	$ 1,000
Preferred Stock, Convertible, Conversion Ratio	93	93
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares	$ 10.725	$ 10.725
Preferred Stock, Convertible, Beneficial Ownership Percentage	9.99%
Series E Preferred Stock [Member] | Maximum [Member]
Preferred Stock, Convertible, Beneficial Ownership Percentage	19.99%
Series H Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share | $ / shares	$ 1,000
Preferred Stock, Convertible, Conversion Ratio	259
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares	$ 3.86
Preferred Stock, Convertible, Beneficial Ownership Percentage	9.99%					9.99%		9.99%
Series H Preferred Stock [Member] | Maximum [Member]
Preferred Stock, Convertible, Beneficial Ownership Percentage	19.99%
Conversion of CRG Loan Into Series E Convertible Preferred Stock [Member]
Debt Conversion, Original Debt, Amount	$ 11,000,000	$ 1,920,000
Debt Conversion, Converted Instrument, Shares Issued (in shares) | shares	11,000	1,920
CRG [Member] | Loan Agreement [Member]
Debt Agreement, Maximum Borrowing Capacity					$ 50,000,000
Debt Instrument, Borrowing Period					24 months
Debt Instrument, Covenant Compliance, Minimum Liquidity Requirement				$ 3,500,000						$ 3,500,000			$ 3,500,000
Debt Instrument, Interest Rate, Stated Percentage			12.50%
Debt Instrument, Periodic Payment			$ 500,000
Long-Term Debt, Maturity, Year Four			1,800,000
Long-Term Debt, Maturity, Year Five			$ 1,800,000
Long Term Debt Maturities, Repayments of Interest in Year Four						$ 400,000		$ 400,000
Long Term Debt Maturities, Repayments of Interest in Year Five						100,000		100,000
Debt Instrument, Redemption Initial Prepayment Premium Percentage			5%
Debt Instrument, Redemption Annual Decline in Prepayment Premium Percentage			1%
Debt Instrument, Financing Fee Percentage			1.50%
Debt Instrument, Final Facility Fee Percentage			15%
Debt Instrument, Covenant Compliance Cash and Certain Cash Equivalents Minimum			$ 3,500,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net					$ 1,300,000	134,000		134,000							$ 166,000
Amortization of Debt Discount (Premium)						8,000	$ 21,000	32,000	$ 62,000
Interest Expense, Debt						$ 116,000	$ 512,000	$ 800,000	$ 1,600,000
CRG [Member] | Loan Agreement [Member] | Series A Preferred Stock Purchase Agreement with CRG [Member]
Debt Conversion, Original Debt, Amount				38,000,000
Debt Conversion, Fees and Prepayment Premium Amount				$ 3,800,000
CRG [Member] | Loan Agreement [Member] | First Tranche, Borrowed on September 22, 2015 [Member]
Debt Instrument, Face Amount					$ 30,000,000
CRG [Member] | Loan Agreement [Member] | Second Tranche, Borrowed on June 15, 2016 [Member]
Debt Instrument, Face Amount																$ 10,000,000
CRG [Member] | Loan Agreement Amendment No 8 [Member]
Debt Instrument, Covenant Compliance, Minimum Liquidity Requirement														$ 1,000,000
CRG [Member] | Loan Agreement Amendment No 10 [Member]
Debt Instrument, Covenant Compliance, Minimum Liquidity Requirement												$ 1,500,000
CRG [Member] | Loan Agreement Amendment No. 7 [Member]
Debt Instrument, Covenant Compliance, Minimum Liquidity Requirement											$ 1,500,000

Note 4 - Borrowings - Schedule

Note 4 - Borrowings - Schedule of Debt (Details) - CRG [Member] - Loan Agreement [Member] $ in Thousands	Sep. 30, 2024 USD ($)
2024 (remaining three months of the year)	$ 0
2025	0
2026	0
2027	2,176
2028	4,060
Total	6,236
Less: Amount of PIK additions and final facility fee to be incurred subsequent to June 30, 2024	(1,934)
Less: Amount representing debt issuance costs	(134)
Borrowings, current portion, as of June 30, 2024	$ 4,168

Note 5 - Leases (Details Textua

Note 5 - Leases (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Mar. 06, 2024	Dec. 31, 2019
Lessee, Operating Lease, Renewal Term (Year)	1 year		1 year
Lessee, Operating Lease, Liability, to be Paid	$ 1,479,000		$ 1,479,000		$ 1,300,000	$ 7,100,000
Operating Lease, Weighted Average Remaining Lease Term	1 year 2 months 12 days		1 year 2 months 12 days
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability			$ 2,200,000
Lessee, Operating Lease, Discount Rate	6.50%		6.50%
Operating Lease, Expense, Excluding Maintenance Fee and Other Expense, Monthly			$ 105,000
Operating Lease, Expense	$ 316,000	$ 314,000	947,000	$ 942,000
Operating Lease, Cost	90,000	65,000	263,000	233,000
Operating Lease, Right-of-Use Asset, Periodic Reduction	$ 290,000	$ 288,000	$ 867,000	$ 852,000

Note 5 - Leases - Future Operat

Note 5 - Leases - Future Operating Lease Payments (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Mar. 06, 2024	Dec. 31, 2023	Dec. 31, 2019
2024 (remaining three months of the year)	$ 313
2025	1,166
Total	1,479	$ 1,300		$ 7,100
Less: Imputed interest	(52)
Leasehold liability as of June 30, 2024	$ 1,427		$ 1,102

Note 5 - Leases - ROU Assets an

Note 5 - Leases - ROU Assets and Lease Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Operating lease	$ 1,427	$ 1,102
Total right of use assets	1,427	1,102
Leasehold liability, current portion	1,210	1,102
Leasehold liability, long-term portion	217	0
Total lease liabilities	$ 1,427	$ 1,102

Note 6 - Commitments and Cont_2

Note 6 - Commitments and Contingencies (Details Textual) $ in Millions	Sep. 30, 2024 USD ($)
Purchase Commitment [Member]
Purchase Obligation	$ 0.7

Note 7 - Stockholders' Equity_2

Note 7 - Stockholders' Equity (Details Textual) $ / shares in Units, $ in Millions								3 Months Ended		9 Months Ended
	Oct. 03, 2024 shares	Aug. 08, 2024 $ / shares shares	Jun. 17, 2024 $ / shares shares	Jun. 13, 2024 $ / shares shares	May 16, 2024 $ / shares shares	Mar. 05, 2024 USD ($) $ / shares shares	Mar. 04, 2024 $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Jun. 13, 2024 $ / shares shares	Sep. 30, 2024 USD ($) $ / shares shares	Aug. 07, 2024 shares	May 22, 2024	Mar. 07, 2024 $ / shares	Dec. 31, 2023 $ / shares shares	Dec. 23, 2023 shares	Aug. 02, 2023 $ / shares	Feb. 16, 2018 $ / shares
Preferred Stock, Shares Authorized (in shares)								5,000,000		5,000,000				5,000,000
Preferred Stock, Par or Stated Value Per Share | $ / shares								$ 0.001		$ 0.001				$ 0.001
Preferred Stock, Shares Issued								30,229		30,229				62,881
Preferred Stock, Shares Outstanding (in shares)								30,229		30,229				62,881
Common Stock, Shares Authorized								100,000,000		100,000,000				100,000,000
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares								$ 0.001		$ 0.001				$ 0.001
Common Stock, Shares, Outstanding, Ending Balance (in shares)								2,783,891		2,783,891				1,279,928
Common Stock, Shares, Issued (in shares)								2,783,891		2,783,891				1,279,928
Class of Warrant or Right, Outstanding (in shares)								51,711,792		51,711,792					41,047,499
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)								13,784,013		13,784,013					456,096
Series A-1 Warrants [Member]
Warrants and Rights Outstanding, Term, Period Following Public Announcement				60 days
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares				$ 1.66					$ 1.66
Number of Warrants Issued Per Unit				1					1
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right				1					1
Series A-2 Warrants [Member]
Warrants and Rights Outstanding, Term, Period Following Public Announcement				60 days
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares				$ 1.66					$ 1.66
Number of Warrants Issued Per Unit				1
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right				1					1
Series A-3 Warrants [Member]
Warrants and Rights Outstanding, Term, Period Following Public Announcement				60 days
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares				$ 1.66					$ 1.66
Number of Warrants Issued Per Unit				1
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right				1					1
Pre-funded Warrants [Member]
Class of Warrant or Right, Exercised (in shares)								867,457
Stock Issued During Period, Shares, Warrants Exercised (in shares)								867,457
Class of Warrant or Right, Outstanding (in shares)								2,417,000		2,417,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares				$ 0.001					$ 0.001
Pre-funded Warrants [Member] | Subsequent Event [Member]
Class of Warrant or Right, Exercised (in shares)	306,000
Class of Warrant or Right, Outstanding (in shares)	2,111,000
Series B Preferred Investment Option Purchase Warrants [Member]
Class of Warrant or Right Warrants Expired		2,853,833
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)											190,259
Class of Warrant or Right, Expired During Period, Exercise Price | $ / shares		$ 22.53
Common Warrants [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares													$ 3.664
Warrants and Rights Outstanding, Term													5 years
Advisor Warrants Issued In The March 2024 Financing [Member]
Class of Warrant or Right, Outstanding (in shares)								40,938		40,938
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						40,938		40,938		40,938
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares								$ 3.664		$ 3.664
Conversion of Warrants Allowed Maximum Ownership of Common Stock Percentage													4.99%
Conversion of Warrants Allowed Maximum Ownership of Common Stock Percentage upon Election													9.99%
Placement Agent Warrants [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares				$ 2.075					$ 2.075
Pre-Funded, Series A-1, Series A-2, Series A-3 and Placement Agent Warrants [Member]
Conversion of Warrants Allowed Maximum Ownership of Common Stock Percentage				4.99%					4.99%
Conversion of Warrants Allowed Maximum Ownership of Common Stock Percentage upon Election				9.99%					9.99%
March 2024 Offering [Member]
Stock Issued During Period, Shares, New Issues						75,327
Shares Issued, Price Per Share | $ / shares						$ 3.664
June 2024 Offering [Member]
Stock Issued During Period, Shares, New Issues			330,000	330,000
Shares Issued, Price Per Share | $ / shares			$ 1.66
Maximum [Member] | Series A-1 Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				3,614,457					3,614,457
Maximum [Member] | Series A-2 Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				3,614,457					3,614,457
Maximum [Member] | Series A-3 Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				3,614,457					3,614,457
Maximum [Member] | Pre-funded Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				3,284,457					3,284,457
Maximum [Member] | Placement Agent Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				216,867					216,867
Series A Preferred Stock [Member]
Preferred Stock, Shares Outstanding (in shares)								0		0
Series A-1 Preferred Stock [Member]
Preferred Stock, Shares Outstanding (in shares)								10,000		10,000
Preferred Stock, Excess Fair Value | $						$ 1.9
Preferred Stock, Stated Value | $ / shares								$ 1,000		$ 1,000
Preferred Stock, Convertible, Conversion Ratio								273		273
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares								$ 3.664		$ 3.664
Preferred Stock, Convertible, Shares Issuable						2,729,257		2,729,257		2,729,257
Preferred Stock, Convertible, Beneficial Ownership Percentage																9.99%
Series A-1 Preferred Stock [Member] | Maximum [Member]
Preferred Stock, Convertible, Beneficial Ownership Percentage								19.99%		19.99%
Series B Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share | $ / shares																	$ 0.001
Preferred Stock, Shares Outstanding (in shares)														85
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares								$ 1.66		$ 1.66				$ 1.66
Series E Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share | $ / shares					$ 1,000											$ 1,000
Preferred Stock, Shares Outstanding (in shares)								1,920		1,920
Preferred Stock, Convertible, Conversion Ratio					93											93
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares					$ 10.725											$ 10.725
Preferred Stock, Convertible, Shares Issuable					178,560
Preferred Stock, Convertible, Beneficial Ownership Percentage					9.99%
Preferred Stock, Dividend Rate, Percentage					8%
Dividends, Preferred Stock | $								$ 0.1		$ 0.1
Series E Preferred Stock [Member] | Maximum [Member]
Preferred Stock, Convertible, Beneficial Ownership Percentage					19.99%
Series F Preferred Stock [Member]
Preferred Stock, Shares Outstanding (in shares)								7,224		7,224
Preferred Stock, Stated Value | $ / shares						$ 1,000
Preferred Stock, Convertible, Conversion Ratio						273	273
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares							$ 3.664
Preferred Stock, Convertible, Beneficial Ownership Percentage							49.90%
Preferred Stock, Dividend Rate, Percentage							5%
Dividends, Preferred Stock | $								$ 0.1		$ 0.2
Stock Issued During Period, Shares, New Issues							7,224
Shares Issued, Price Per Share | $ / shares							$ 1,000
Preferred Stock Dividend Rate, Percentage, Thereafter Third Anniversary Of Issuance							8%
Series F Preferred Stock [Member] | Maximum [Member]
Preferred Stock, Convertible, Beneficial Ownership Percentage												19.90%
Series F Convertible Preferred Stock [Member]
Preferred Stock, Convertible, Shares Issuable							1,972,152
Series H Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share | $ / shares					$ 1,000
Preferred Stock, Shares Outstanding (in shares)								11,000		11,000
Preferred Stock, Convertible, Conversion Ratio					259
Preferred Stock, Convertible, Conversion Price (in dollars per share) | $ / shares					$ 3.86
Preferred Stock, Convertible, Shares Issuable					2,849,000
Preferred Stock, Convertible, Beneficial Ownership Percentage					9.99%			9.99%		9.99%
Preferred Stock, Dividend Rate, Percentage					8%
Dividends, Preferred Stock | $								$ 0.2		$ 0.3
Stock Issued During Period, Shares, New Issues					11,000
Shares Issued, Price Per Share | $ / shares					$ 1,000
Series H Preferred Stock [Member] | Maximum [Member]
Preferred Stock, Convertible, Beneficial Ownership Percentage					19.99%
Exchange of Series A Preferred Stock Into Series A-1 Preferred Stock [Member]
Conversion of Stock, Shares Converted						60,876
Conversion of Stock, Shares Issued						10,000

Note 7 - Stockholder's Equity -

Note 7 - Stockholder's Equity - Outstanding Warrants (Details) - $ / shares	Sep. 30, 2024	Mar. 05, 2024	Dec. 23, 2023
Total Outstanding and Exercisable (in shares)	51,711,792		41,047,499
Underlying Shares of Common Stock (in shares)	13,784,013		456,096
Series 1 February 2018 Warrants [Member]
Total Outstanding and Exercisable (in shares)	8,979,000		8,979,000
Underlying Shares of Common Stock (in shares)	2,993		2,993
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 6,000		$ 6,000
Series 2 February 2018 Warrants [Member]
Total Outstanding and Exercisable (in shares)	8,709,500		8,709,500
Underlying Shares of Common Stock (in shares)	2,903		2,903
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 6,000		$ 6,000
Placement agent warrants issued in the January 2022 financing [Member]
Total Outstanding and Exercisable (in shares)	1,330,000		1,330,000
Underlying Shares of Common Stock (in shares)	4,433		4,433
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 150		$ 150
Warrants Issued in the January 2022 Financing [Member]
Total Outstanding and Exercisable (in shares)	16,150,000		16,150,000
Underlying Shares of Common Stock (in shares)	53,833		53,833
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 144		$ 144
Series A Private Investment Options Issued in August 2022 Financing [Member]
Total Outstanding and Exercisable (in shares)	2,853,883		2,853,883
Underlying Shares of Common Stock (in shares)	190,259		190,259
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 22.53		$ 22.53
Series B Private Investment Options Issued in August 2022 Financing [Member]
Total Outstanding and Exercisable (in shares)	171,233		2,853,883
Underlying Shares of Common Stock (in shares)	11,416		190,259
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 32.85		$ 22.53
Placement Agent Private Investment Options Issued in August 2022 Financing [Member]
Total Outstanding and Exercisable (in shares)			171,233
Underlying Shares of Common Stock (in shares)			11,416
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 32.85
Advisor Warrants Issued In The March 2024 Financing [Member]
Total Outstanding and Exercisable (in shares)	40,938
Underlying Shares of Common Stock (in shares)	40,938	40,938
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 3.664
Prefunded Warrants Issued in June 2024 [Member]
Total Outstanding and Exercisable (in shares)	2,417,000
Underlying Shares of Common Stock (in shares)	2,417,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 0.001
Series A-1 Warrants Issued in June 2024 [Member]
Total Outstanding and Exercisable (in shares)	3,614,457
Underlying Shares of Common Stock (in shares)	3,614,457
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 1.66
Series A-2 Warrants Issued in June 2024 [Member]
Total Outstanding and Exercisable (in shares)	3,614,457
Underlying Shares of Common Stock (in shares)	3,614,457
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 1.66
Series A-3 Warrants Issued in June 2024 [Member]
Total Outstanding and Exercisable (in shares)	3,614,457
Underlying Shares of Common Stock (in shares)	3,614,457
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 1.66
Placement Agent Warrants Issued in June 2024 [Member]
Total Outstanding and Exercisable (in shares)	216,867
Underlying Shares of Common Stock (in shares)	216,867
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 2.075

Note 8 - Stock-based Compensa_3

Note 8 - Stock-based Compensation (Details Textual) - USD ($)		3 Months Ended		9 Months Ended
	Dec. 22, 2023	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Share Price		$ 0.95		$ 0.95
Share-Based Payment Arrangement, Expense		$ 222,000	$ 219,000	$ 1,525,000	$ 703,000
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		300,000		$ 300,000
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				3 months 18 days
Sharebased Compensation Arrangement by Sharebased Payment Award Equity Instruments Other than Options Nonvested Fair Value		100,000		$ 100,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value				1,000,000	100,000
Share-Based Payment Arrangement, Expense		$ 222,000	$ 219,000	$ 1,500,000	$ 700,000
The 2015 Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized	300,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross				15
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant		71,442		71,442

Note 8 - Stock-Based Compensa_4

Note 8 - Stock-Based Compensation - Stock Option Activity (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Awards outstanding, shares (in shares)	90,190
Awards outstanding, Weighted Average Grant Date Fair Value (in dollars per share)	$ 18.45
Awards outstanding, Weighted Average Remaining Contractual Term (Year)	3 months 18 days	1 year 14 days
Awarded, shares (in shares)	394,105
Awarded, Weighted Average Grant Date Fair Value (in dollars per share)	$ 2.75
Released, shares (in shares)	(368,503)
Released, Weighted Average Grant Date Fair Value (in dollars per share)	$ 4.89
Forfeited, shares (in shares)	(3,333)
Forfeited, , Weighted Average Grant Date Fair Value (in dollars per share)	$ 18.45
Awards outstanding, shares (in shares)	112,459	90,190
Awards outstanding, Weighted Average Grant Date Fair Value (in dollars per share)	$ 7.85	$ 18.45

Note 8 - Stock-based Compensa_5

Note 8 - Stock-based Compensation - Noncash Stock-based Compensation Expense Related to Stock Options, ESPP, and RSUs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Allocated Share-based Compensation Expense	$ 222	$ 219	$ 1,525	$ 703
Cost of Sales [Member]
Allocated Share-based Compensation Expense	36	36	228	99
Research and Development Expense [Member]
Allocated Share-based Compensation Expense	42	24	397	158
Selling, General and Administrative Expenses [Member]
Allocated Share-based Compensation Expense	$ 144	$ 159	$ 900	$ 446

Note 9 - Restructuring Charge_2

Note 9 - Restructuring Charges and Expenses (Details Textual)	1 Months Ended	3 Months Ended	9 Months Ended
	Jun. 30, 2024 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2024 USD ($)
Restructuring and Related Cost, Number of Positions Eliminated, Period Percent	24%
Restructuring and Related Cost, Number of Positions Eliminated	17
Severance Costs	$ 66,000
Restructuring and Related Cost, Number of Positions Eliminated, Severance Paid	17
Severance Costs, Included in Accrued Compensation			$ 4,000
Research and Development Expense [Member]
Severance Costs		$ 14,000
Selling, General and Administrative Expenses [Member]
Severance Costs		$ 53,000	$ 23,000