Avinger (AVGR) 10-Q 31 Jul 20 2020 Q2 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	6 Months Ended
	Jun. 30, 2020	Jul. 27, 2020
Document Information [Line Items]
Entity Registrant Name	Avinger Inc
Entity Central Index Key	0001506928
Trading Symbol	avgr
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Current Reporting Status	Yes
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Small Business	true
Entity Interactive Data Current	Yes
Entity Common Stock, Shares Outstanding (in shares)		54,339,024
Entity Shell Company	false
Document Type	10-Q
Document Period End Date	Jun. 30, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Amendment Flag	false
Title of 12(b) Security	Common Stock, par value $0.001 per share

Condensed Balance Sheets (Curre

Condensed Balance Sheets (Current Period Unaudited) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 16,550,000	$ 10,943,000
Accounts receivable, net of allowance for doubtful accounts of $19 at both June 30, 2020 and December 31, 2019	1,076,000	1,458,000
Inventories	4,157,000	3,912,000
Prepaid expenses and other current assets	899,000	311,000
Total current assets	22,682,000	16,624,000
Right of use asset	4,468,000	4,856,000
Property and equipment, net	1,140,000	1,661,000
Other assets	594,000	684,000
Total assets	28,884,000	23,825,000
Current liabilities:
Accounts payable	924,000	663,000
Accrued compensation	1,151,000	1,782,000
Series A preferred stock dividends payable	1,934,000
Accrued expenses and other current liabilities	730,000	654,000
Leasehold liability, current portion	765,000	722,000
Borrowings, current portion	10,808,000	8,967,000
Total current liabilities	16,312,000	12,788,000
Leasehold liability, long-term portion	3,703,000	4,135,000
Borrowings, long-term portion	1,301,000
Other long-term liabilities	19,000	7,000
Total liabilities	21,335,000	16,930,000
Commitments and contingencies (Note 6)
Stockholders’ equity:
Convertible preferred stock issuable in series, par value of $0.001; Shares authorized: 5,000,000 at June 30, 2020 and December 31, 2019; Shares issued and outstanding: 48,503 at June 30, 2020 and December 31, 2019; aggregate liquidation preference of $48,503 at June 30, 2020 and December 31, 2019
Common stock, par value of $0.001; Shares authorized: 100,000,000 at June 30, 2020 and December 31, 2019; Shares issued and outstanding: 51,339,024 and 10,364,663 at June 30, 2020 and December 31, 2019, respectively	51,000	10,000
Additional paid-in capital	365,684,000	355,220,000
Accumulated deficit	(358,186,000)	(348,335,000)
Total stockholders’ equity	7,549,000	6,895,000
Total liabilities and stockholders’ equity	$ 28,884,000	$ 23,825,000

Condensed Balance Sheets (Cur_2

Condensed Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Accounts receivable, allowance for doubtful accounts	$ 19	$ 19
Preferred stock, par value (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)	48,503	48,503
Preferred stock, shares outstanding (in shares)	48,503	48,503
Preferred stock, liquidation preference	$ 48,503	$ 48,503
Common stock, par value (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)	51,339,024	10,364,663
Common stock, shares outstanding (in shares)	51,339,024	10,364,663

Condensed Statements of Operati

Condensed Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Revenues	$ 1,466	$ 2,319	$ 3,727	$ 4,159
Cost of revenues	1,107	1,599	2,867	3,066
Gross profit	359	720	860	1,093
Operating expenses:
Research and development	1,297	1,335	2,891	2,749
Selling, general and administrative	2,654	4,091	7,040	8,077
Total operating expenses	3,951	5,426	9,931	10,826
Loss from operations	(3,592)	(4,706)	(9,071)	(9,733)
Interest income	2	90	32	172
Interest expense	(414)	(364)	(812)	(714)
Other income, net	4	329		569
Net loss and comprehensive loss	(4,000)	(4,651)	(9,851)	(9,706)
Accretion of preferred stock dividends	(967)	(895)	(1,934)	(1,790)
Net loss attributable to common stockholders	$ (4,967)	$ (5,546)	$ (11,785)	$ (11,496)
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.18)	$ (0.87)	$ (0.56)	$ (2.16)
Weighted average common shares used to compute net loss per share, basic and diluted (in shares)	27,310	6,377	20,963	5,319

Condensed Statements of Stockho

Condensed Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	August Public Offering [Member]Preferred Stock [Member]	August Public Offering [Member]Common Stock [Member]	August Public Offering [Member]Additional Paid-in Capital [Member]	August Public Offering [Member]Retained Earnings [Member]	August Public Offering [Member]	Conversion of Series B Preferred Stock into Common Stock [Member]Preferred Stock [Member]	Conversion of Series B Preferred Stock into Common Stock [Member]Common Stock [Member]	Conversion of Series B Preferred Stock into Common Stock [Member]Additional Paid-in Capital [Member]	Conversion of Series B Preferred Stock into Common Stock [Member]Retained Earnings [Member]	Conversion of Series B Preferred Stock into Common Stock [Member]	Conversion of Series C Preferred Stock into Common Stock [Member]Preferred Stock [Member]	Conversion of Series C Preferred Stock into Common Stock [Member]Common Stock [Member]	Conversion of Series C Preferred Stock into Common Stock [Member]Additional Paid-in Capital [Member]	Conversion of Series C Preferred Stock into Common Stock [Member]Retained Earnings [Member]	Conversion of Series C Preferred Stock into Common Stock [Member]	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2018																45,671	3,492,200
Balance at Dec. 31, 2018																	$ 3	$ 338,342	$ (328,885)	$ 9,460
Issuance of common stock under officers and directors purchase plan (in shares)																	7,788
Issuance of common stock under officers and directors purchase plan																		36		36
Employee stock-based compensation																		1,009		1,009
Exercises of warrants for common stock (in shares)																	1,998,079
Exercises of warrants for common stock																	$ 2	7,991		7,993
Accretion of Series A preferred stock dividends																		(1,790)		(1,790)
Net and comprehensive loss																			(9,706)	(9,706)
Conversion of convertible securities (in shares)						(1,523)	380,750				(2,170)	542,500
Conversion of convertible securities												$ 1	$ (1)
Issuance of Series A preferred stock to pay dividends (in shares)																2,945
Issuance of Series A preferred stock to pay dividends																		2,918		2,918
Balance (in shares) at Jun. 30, 2019																44,923	6,421,317
Balance at Jun. 30, 2019																	$ 6	348,505	(338,591)	9,920
Balance (in shares) at Mar. 31, 2019																44,923	6,005,218
Balance at Mar. 31, 2019																	$ 6	347,213	(333,940)	13,279
Issuance of common stock under officers and directors purchase plan (in shares)																	3,099
Issuance of common stock under officers and directors purchase plan																		18		18
Employee stock-based compensation																		516	451	516
Exercises of warrants for common stock (in shares)																	413,000
Exercises of warrants for common stock																		1,653		1,653
Accretion of Series A preferred stock dividends																		(895)		(895)
Net and comprehensive loss																			(4,651)	(4,651)
Balance (in shares) at Jun. 30, 2019																44,923	6,421,317
Balance at Jun. 30, 2019																	$ 6	348,505	(338,591)	9,920
Balance (in shares) at Dec. 31, 2019																48,503	10,364,663
Balance at Dec. 31, 2019																	$ 10	355,220	(348,335)	6,895
Issuance of common stock under officers and directors purchase plan (in shares)																	55,789
Issuance of common stock under officers and directors purchase plan																		27		27
Employee stock-based compensation																		776	451	776
Accretion of Series A preferred stock dividends																		(1,934)		(1,934)
Net and comprehensive loss																			(9,851)	(9,851)
Issuance of common stock in public offerings, net of commissions and issuance costs (in shares)		40,918,572
Issuance of common stock in public offerings, net of commissions and issuance costs		$ 41	$ 11,595		$ 11,636
Balance (in shares) at Jun. 30, 2020																48,503	51,339,024
Balance at Jun. 30, 2020																	$ 51	365,684	(358,186)	7,549
Balance (in shares) at Mar. 31, 2020																48,503	16,821,359
Balance at Mar. 31, 2020																	$ 17	358,577	(354,186)	4,408
Issuance of common stock under officers and directors purchase plan (in shares)																	27,665
Issuance of common stock under officers and directors purchase plan																		9		9
Employee stock-based compensation																		325	451	325
Accretion of Series A preferred stock dividends																		(967)		(967)
Net and comprehensive loss																			(4,000)	(4,000)
Issuance of common stock in public offerings, net of commissions and issuance costs (in shares)		34,490,000
Issuance of common stock in public offerings, net of commissions and issuance costs		$ 34	$ 7,740		$ 7,774
Balance (in shares) at Jun. 30, 2020																48,503	51,339,024
Balance at Jun. 30, 2020																	$ 51	$ 365,684	$ (358,186)	$ 7,549

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities
Net loss	$ (9,851)	$ (9,706)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	453	428
Amortization of debt issuance costs and debt discount	84	86
Stock-based compensation	776	1,009
Noncash interest expense	728	629
Change in right of use asset	86	(179)
Provision for excess and obsolete inventories	253	97
Other non-cash (gains) losses, net	(29)
Changes in operating assets and liabilities:
Accounts receivable	382	(56)
Inventories	(465)	(1,066)
Prepaid expenses and other current assets	(532)	(334)
Other assets	4
Accounts payable	261	(62)
Accrued compensation	(631)	242
Accrued expenses and other current liabilities	76	(673)
Other long-term liabilities	10	(30)
Net cash used in operating activities	(8,395)	(9,615)
Cash flows from investing activities
Purchases of property and equipment		(88)
Proceeds from sale of property and equipment		18
Net cash used in investing activities		(70)
Cash flows from financing activities
Proceeds from borrowings, net of issuance costs	2,330
Proceeds from the issuance of common stock related to warrant exercises		7,993
Proceeds from the issuance of common stock in public offerings, net	11,636
Proceeds from the issuance of common stock under officers and directors purchase plan	36	36
Net cash provided by financing activities	14,002	8,029
Net change in cash and cash equivalents	5,607	(1,656)
Cash and cash equivalents, beginning of period	10,943	16,410
Cash and cash equivalents, end of period	16,550	14,754
Noncash investing and financing activities:
Accretion of Series A preferred stock dividends	1,934	1,790
Issuance of Series A preferred stock to pay dividends		2,918
Reclassification of right of use asset to prepaid rent	(86)	179
Increase to right of use asset and leasehold liability arising from lease amendment		4,680
Transfers between inventory and property and equipment	$ (32)	$ 287

Note 1 - Organization

Note 1 - Organization	6 Months Ended
	Jun. 30, 2020
Notes to Financial Statements
Nature of Operations [Text Block]	1. Organization, Nature of Business Avinger, Inc. (the “Company”), a Delaware corporation, was incorporated in March 2007. “OCT”) 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 one In the course of its activities, the Company has incurred losses and negative cash flows from operations since its inception. As of June 30, 2020, $358.2 $16.6 June 30, 2020 second 2021. $5.5 June July 2020, $3.0 April May 2020, $2.3 $3.9 January 2020 $3.8 August 2019 $8 April May 2019, twelve may The Company can provide no not twelve no 19 second 2020 19 20% 20%. July 2020, no 19 may one not 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 borrowings at June 30, 2020 December 31, 2019 not Public Offerings On August 26, 2019, 3,813,559 $1.18 $3.8 February 2018 $1.18 On January 31, 2020, 6,428,572 $0.70 $3.9 February 2018 $0.70 On April 30, 2020, 12,600,000 $0.25 May 6, 2020 1,890,000 $3.0 February 2018 $0.25 On June 26, 2020, 20,000,000 $0.27 July 9, 2020 3,000,000 $5.5

Note 2 - Summary of Significant

Note 2 - Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2020
Notes to Financial Statements
Basis of Presentation and Significant Accounting Policies [Text Block]	2. 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 (“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 six June 30, 2020 not December 31, 2020, December 31, 2019 10 December 31, 2019, March 5, 2020. 2 10 December 31, 2019. On June 19, 2019, 1 10 June 21, 2019. not 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 common stock valuation and related stock-based compensation, the valuation of the common stock warrants, the valuation of compound embedded derivatives, 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 may may Fair Value of Financial Instruments The Company has evaluated the estimated fair value of its financial instruments as of June 30, 2020 December 31, 2019. Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three June 30, 2020 December 31, 2019, no June 30, 2020 December 31, 2019. 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 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 June 30, 2020 December 31, 2019. The Company's accounts receivable are due from a variety of healthcare organizations in the United States and select international markets. At June 30, 2020 December 31, 2019, no 10% three six June 30, 2020 2019, no 10% The Company manufactures its commercial products in-house, including the Pantheris and Ocelot family of catheters. Certain of the Company's product components and sub-assemblies continue to be manufactured by sole suppliers, including internally. Disruption in component or sub-assembly supply from these manufacturers or from in-house production would have a negative impact on the Company's financial position and results of operations. The Company is subject to certain risks, including that its devices may not no not third Existing or future devices developed by the Company may may may Revenue Recognition The Company's revenues are derived from ( 1 2 3 1. Lightbox sales: The Company sells its products directly to hospitals and medical centers. Provided all other criteria for revenue recognition have been met, the Company recognizes revenue for Lightbox sales directly to end customers when delivery and acceptance occurs, which is defined as receipt by the Company of an executed form by the customer acknowledging that the training and installation process is complete. 2. Sales of disposables: Disposable revenues consist of sales of the Company's catheters and accessories and are recognized when the product has shipped, risk of loss and title has passed to the customer and collectability is reasonably assured. 3. Service revenue: Service contract revenue is recognized ratably over the term of the service period and maintenance contract revenue is recognized as work is performed. To date, service revenue has been insignificant. The Company offers its customers the ability to purchase or lease its Lightbox. In addition, the Company provides a Lightbox under a limited commercial evaluation program to allow certain strategic accounts to install and utilize the Lightbox for a limited trial period of typically three six The Company evaluates its lease and commercial evaluation program agreements and accounts for these contracts under the guidance in Accounting Standards Codification (“ASC”) 842, Leases No. 2014 09, Revenue from Contracts with Customers (Topic 606 The Company assessed whether the embedded lease is an operating lease or sales-type lease. Based on the Company's assessment of the guidance and given that any payments under the lease agreements are dependent upon contingent future sales, it was determined that collectability of the minimum lease payments is not not For sales through distributors, the Company recognizes revenue when control of the product transfers from the Company to the distributor. The distributors are responsible for all marketing, sales, training, and warranty in their respective territories. The standard terms and conditions contained in the Company's distribution agreements do not not The Company estimates reductions in revenue for potential returns of products by customers. In making such estimates, management analyzes historical returns, current economic trends and changes in customer demand and acceptance of its products. The Company expenses shipping and handling costs as incurred and includes them in the cost of revenues. When the Company bills shipping and handling costs to customers, such amounts billed are included as a component of revenue. Cost of Revenues Cost of revenues consists primarily of manufacturing overhead costs, material costs and direct labor. A significant portion of the Company's cost of revenues currently consists of manufacturing overhead costs. These overhead costs include the cost of quality assurance, material procurement, inventory control, facilities, equipment and operations supervision and management. Cost of revenues also includes depreciation expense for the Lightboxes under lease and evaluation agreements, product warranty costs, product written-off due to excess or obsolescence, and certain direct costs such as shipping costs. Product Warranty Costs The Company typically offers a one Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 Beginning balance $ 221 $ 206 $ 215 $ 272 Warranty provision 50 34 111 36 Usage/Release (50 ) (25 ) (105 ) (93 ) Ending balance $ 221 $ 215 $ 221 $ 215 Net Loss per Share Attributable to Common Stockholders Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable 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 attributable to common stockholder 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 June 30, 2020 2019, no Net loss per share attributable to common stockholders was determined as follows (in thousands, except per share data): Three Months Ended June 30, Six Months Ended June 30, 20 20 201 9 20 20 201 9 Net loss attributable to common stockholders $ (4,967 ) $ (5,546 ) $ (11,785 ) $ (11,496 ) Weighted average common stock outstanding, basic and diluted 27,310 6,377 20,963 5,319 Net loss per share attributable to common stockholders, basic and diluted $ (0.18 ) $ (0.87 ) $ (0.56 ) $ (2.16 ) 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 June 30, Six Months Ended June 30, 20 20 201 9 20 20 2019 Common stock warrants equivalents 2,753,999 2,801,606 2,753,999 3,645,862 Common stock options 7,133 7,492 7,200 7,673 Convertible preferred stock 48,503 44,923 48,503 45,109 Unvested restricted stock units 839,804 287,817 856,749 288,581 3,649,439 3,141,838 3,666,451 3,987,225 Segment and Geographical Information The Company operates and manages its business as one three June 30, 2020 2019, 93% 92%, six June 30, 2020 2019, 96% 92%, Recent Accounting Pronouncements Recently adopted accounting standards In June 2016, 2016 13, Financial Instruments – Credit Losses first 2020. not Recent accounting standards not In December 2019, 2019 12, Income Taxes (Topic 740 first 2021 not

Note 3 - Fair Value Measurement

Note 3 - Fair Value Measurements	6 Months Ended
	Jun. 30, 2020
Notes to Financial Statements
Fair Value Disclosures [Text Block]	3. The Company measures certain financial assets and liabilities at fair value on a recurring basis. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. A three Level 1 Quoted prices in active markets for identical assets or liabilities. Level 2 Inputs other than quoted prices included within Level 1 not Level 3 Unobservable inputs that are supported by little or no As of June 30, 2020 December 31, 2019, 1 June 30, 2020 December 31, 2019, no 2 3. no three June 30, 2020.

Note 4 - Inventories

Note 4 - Inventories	6 Months Ended
	Jun. 30, 2020
Notes to Financial Statements
Inventory Disclosure [Text Block]	4. Inventories consisted of the following (in thousands): June 30, December 31, 20 20 201 9 Raw materials $ 2,040 $ 1,426 Work-in-process 402 596 Finished products 1,715 1,890 Total inventories $ 4,157 $ 3,912

Note 5 - Borrowings

Note 5 - Borrowings	6 Months Ended
	Jun. 30, 2020
Notes to Financial Statements
Debt Disclosure [Text Block]	5. CRG On September 22, 2015, $50 March 29, 2017. $30 September 22, 2015. $10 June 15, 2016 On February 14, 2018, $38 $3.8 On March 2, 2020, No. 3 ● extend the period that the Company can make interest payments in payment in kind (“PIK”) to June 30, 2021 ● lower the Minimum Revenue Covenants to $10 2020, $12 2021, $15 2022; ● insert certain terms to clarify that all fees, including the prepayment premium, are due if the obligations are accelerated; and ● insert a new provision to make clear that to the extent the Company divides its assets/liabilities into divisions, such assets/liabilities will be treated as transferred to a third On May 12, 2020, No. 4 ● grant to the Company the right to optionally prepay in whole or in part the outstanding principal amount of the Loans for the Redemption Price, subject to certain conditions; and ● waive the Company's requirement to comply with the Minimum Revenue Covenant for 2020. Under the amended Loan Agreement, no third 2021. not 12.5%. third 2021, $1.4 $2.7 2021, $5.5 2022 $2.7 2023. June 30, 2023. The Company may 5.0% 1.0% no seven 1.5% 15.0% The Loan Agreement requires that the Company adheres to certain affirmative and negative covenants, including financial reporting requirements, certain minimum financial covenants for pre-specified liquidity and revenue requirements 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 2.0 may As of June 30, 2020, As of June 30, 2020, Year Ending December 31, 2020 (remaining six months of the year) $ — 2021 3,400 2022 6,266 2023 4,518 14,184 Less: Amount of PIK additions and final facility fee to be accreted subsequent to June 30, 2020 (3,905 ) Less: Amount representing debt financing costs (503 ) Borrowings, as of June 30, 2020 $ 9,776 In connection with drawdowns under the Loan Agreement, the Company recorded aggregate debt discounts of $1.3 June 30, 2020 December 31, 2019, $503,000 $588,000, $42,000 $43,000 three June 30, 2020 2019, $84,000 $86,000 six June 30, 2020 2019, three June 30, 2020 2019, $410,000 $364,000, six June 30, 2020 2019, $808,000 $714,000, 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, the entire amount of borrowings at June 30, 2020 December 31, 2019 not Paycheck Protection Program On April 23, 2020, $2.3 The Loan, which was in the form of a promissory note, dated April 20, 2020 ( April 20, 2022 1% six may no Under the terms of the PPP, the principal may No may The Promissory Note evidencing the PPP Loan contains customary representations, warranties, and covenants for this type of transaction, including customary events of default relating to, among other things, payment defaults and breaches of representations and warranties or other provisions of the Promissory Note. The occurrence of an event of default may As of June 30, 2020, Year Ending December 31, 2020 (remaining six months of the year) $ 264 2021 1,575 2022 521 2,360 Less: Amount of interest to be accreted subsequent to June 30, 2020 (27 ) Borrowings, as of June 30, 2020 $ 2,333 For the three six June 30, 2020, $4,000

Note 6 - Commitments and Contin

Note 6 - Commitments and Contingencies	6 Months Ended
	Jun. 30, 2020
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	6. Lease Commitments The Company's operating lease obligations primarily consist of leased office, laboratory, and manufacturing space under a non-cancelable operating lease that originally were to expire in November 2019. On October 19, 2017, one December 1, 2017 November 15, 2019 15 $82,410 Upon the adoption of Topic 842 January 1, 2019, $1.8 On April 1, 2019, five November 30, 2019. November 30, 2024. $5.8 November 2024, December 1, 2019. not In connection with the amendment the Company adjusted its right-of-use asset and lease liability to $6.0 6.5% For the three June 30, 2020, $105,000, $314,000 three June 30, 2020 2019. six June 30, 2020 2019 $628,000 $806,000, three June 30, 2020 2019 $239,000 $219,000, six June 30, 2020 2019 $475,000 $219,000, $375,000 June 30, 2020. The following table presents the future operating lease payments and lease liability included on the condensed balance sheet related to the Company's operating lease as of June 30, 2020 ( Year Ending December 31, 2020 (remaining six months of the year) $ 544 2021 1,123 2022 1,162 2023 1,203 2024 1,138 5,170 Less: Imputed interest (702 ) Leasehold liability as of June 30, 2020 $ 4,468 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 $1.0 June 30, 2020. Indemnification In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and may may not not The Company indemnifies each of its directors and officers for certain events or occurrences, subject to certain limits, while the director is or was serving at the Company's request in such capacity, as permitted under Delaware law and in accordance with its certificate of incorporation and bylaws. The term of the indemnification period lasts as long as a director may may not

Note 7 - Stockholders' Equity

Note 7 - Stockholders' Equity	6 Months Ended
	Jun. 30, 2020
Notes to Financial Statements
Stockholders' Equity Note Disclosure [Text Block]	7. Convertible Preferred Stock As of June 30, 2020, 5,000,000 $0.001 48,503 Series A Convertible Preferred Stock On February 14, 2018, $38.0 $3.8 $41.8 2,090,000 8%, no January 2019 December 2019, 2,945 3,580 December 31, 2019. June 30, 2020, 48,325 $967,000 $895,000 June 30, 2020 2019, $1.9 $1.8 six June 30, 2020 2019, Series B Convertible Preferred Stock On February 16, 2018, 17,979 $15.5 $0.001 no no not December 31, 2019, 1,523 380,750 June 30, 2020 December 31, 2019, 178 $0.25 Series C Convertible Preferred Stock On November 1, 2018, 728,500 8,586 $10.2 $0.001 no six June 30, 2019, 2,170 542,500 no Common Stock As of June 30, 2020, 100,000,000 $0.001 51,339,024 Common Stock Warrants As of June 30, 2020, Total Outstanding and Exercisable Underlying Shares of Common Stock Exercise Price per Share Expiration Date Series 1 Warrants issued in February 2018 financing 8,979,000 897,900 $ 20.00 February 2025 Series 2 Warrants issued in February 2018 financing 8,709,500 870,950 $ 20.00 February 2025 Warrants issued in July 2018 financing 1,083,091 108,309 $ 15.80 July 2021 Warrants issued in November 2018 financing 8,768,395 876,840 $ 4.00 November 2023 Total 27,539,986 2,753,999 In connection with the issuance of the Company's Series E convertible preferred stock in September 2014 January 2015, 50% September 2, 2019. On February 16, 2018, two 1,797,900 one one $4.00 seventh 50 one seventh 60th 50 60 seven April 2019, 60 60 2 seventh June 30, 2020, 1,768,850 On July 13, 2018, 216,618 108,309 $15.80 one one third June 30, 2020, On November 1, 2018, 728,500 8,586 2,875,000 one one $4.00 5th one 250 December 31, 2019, 1,998,079 $8.0 June 30, 2020 December 31, 2019, 876,840 As of June 30, 2020 December 31, 2019, 2,753,999 Stock Plans In January 2015, 2015 “2015 2015 2009 “2009 2015 3,300 2015 2015 not 2009 2009 2015 first 2016, 4,225 5.0% 2018, 300,000 2015 June 8, 2018. June 19, 2019, 800,000 2015 June 30, 2020, 187,753 2015 Pursuant to the Plans, ISOs and NSOs may not 100% 10% not 110% four ten Stock option activity under the Plans is set forth below: Number of (in thousands) Weighted Average Price Weighted Average Remaining Contractual Life (in years) Intri n sic Value (in thousands) Balance at December 31, 2019 7,401 $ 1,309.47 6.81 $ — Granted — $ — Exercised — $ — Expired (23 ) $ 820.00 Forfeited (297 ) $ 1,705.58 Balance at June 30, 2020 7,081 $ 1,291.74 6.10 $ — Exercisable at June 30, 2020 7,004 $ 1,296.85 6.09 $ — Vested and expected to vest at June 30, 2020 7,081 $ 1,291.74 6.10 $ — There were no six June 30, 2020 2019. June 30, 2020, $20,000 0.7 not three six June 30, 2020 2019. The Company's RSUs generally vest annually over three four Number of Shares Weighted Average Grant Date Fair Value Weighted Average Remaining Contractual Term Awards outstanding at December 31, 2019 908,504 $ 4.09 1.81 Awarded 47,500 $ 0.58 — Released (2,755 ) $ 72.65 — Forfeited (138,062 ) $ 3.04 — Awards outstanding at June 30, 2020 815,187 $ 3.83 1.41 As of June 30, 2020, $1.9 1.4 815,187 $0.3 $0.31 June 30, 2020, six June 30, 2020 2019, $1,200 $565, 2018 On August 22, 2018, may 20,000 August 28, 2019 March 10, 2020, 40,000 125,000 six June 30, 2020 53,034 June 30, 2020, 92,170

Note 8 - Stock-based Compensati

Note 8 - Stock-based Compensation	6 Months Ended
	Jun. 30, 2020
Notes to Financial Statements
Share-based Payment Arrangement [Text Block]	8. Total noncash stock-based compensation expense relating to the Company's stock options and RSUs recognized during the three six June 30, 2020 2019, Three Months Ended June 30, Six Months Ended June 30, 20 20 201 9 20 20 201 9 Cost of revenues $ 27 $ 40 $ 61 $ 87 Research and development expenses 106 116 238 218 Selling, general and administrative expenses 192 360 477 704 $ 325 $ 516 $ 776 $ 1,009

Significant Accounting Policies

Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2020
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 (“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 six June 30, 2020 not December 31, 2020, December 31, 2019 10 December 31, 2019, March 5, 2020. 2 10 December 31, 2019. On June 19, 2019, 1 10 June 21, 2019. not
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 common stock valuation and related stock-based compensation, the valuation of the common stock warrants, the valuation of compound embedded derivatives, 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 may may
Fair Value Measurement, Policy [Policy Text Block]	Fair Value of Financial Instruments The Company has evaluated the estimated fair value of its financial instruments as of June 30, 2020 December 31, 2019.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash and Cash Equivalents The Company considers all highly liquid investments with an original maturity of three June 30, 2020 December 31, 2019, no June 30, 2020 December 31, 2019.
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 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 June 30, 2020 December 31, 2019. The Company's accounts receivable are due from a variety of healthcare organizations in the United States and select international markets. At June 30, 2020 December 31, 2019, no 10% three six June 30, 2020 2019, no 10% The Company manufactures its commercial products in-house, including the Pantheris and Ocelot family of catheters. Certain of the Company's product components and sub-assemblies continue to be manufactured by sole suppliers, including internally. Disruption in component or sub-assembly supply from these manufacturers or from in-house production would have a negative impact on the Company's financial position and results of operations. The Company is subject to certain risks, including that its devices may not no not third Existing or future devices developed by the Company may may may
Revenue from Contract with Customer [Policy Text Block]	Revenue Recognition The Company's revenues are derived from ( 1 2 3 1. Lightbox sales: The Company sells its products directly to hospitals and medical centers. Provided all other criteria for revenue recognition have been met, the Company recognizes revenue for Lightbox sales directly to end customers when delivery and acceptance occurs, which is defined as receipt by the Company of an executed form by the customer acknowledging that the training and installation process is complete. 2. Sales of disposables: Disposable revenues consist of sales of the Company's catheters and accessories and are recognized when the product has shipped, risk of loss and title has passed to the customer and collectability is reasonably assured. 3. Service revenue: Service contract revenue is recognized ratably over the term of the service period and maintenance contract revenue is recognized as work is performed. To date, service revenue has been insignificant. The Company offers its customers the ability to purchase or lease its Lightbox. In addition, the Company provides a Lightbox under a limited commercial evaluation program to allow certain strategic accounts to install and utilize the Lightbox for a limited trial period of typically three six The Company evaluates its lease and commercial evaluation program agreements and accounts for these contracts under the guidance in Accounting Standards Codification (“ASC”) 842, Leases No. 2014 09, Revenue from Contracts with Customers (Topic 606 The Company assessed whether the embedded lease is an operating lease or sales-type lease. Based on the Company's assessment of the guidance and given that any payments under the lease agreements are dependent upon contingent future sales, it was determined that collectability of the minimum lease payments is not not For sales through distributors, the Company recognizes revenue when control of the product transfers from the Company to the distributor. The distributors are responsible for all marketing, sales, training, and warranty in their respective territories. The standard terms and conditions contained in the Company's distribution agreements do not not The Company estimates reductions in revenue for potential returns of products by customers. In making such estimates, management analyzes historical returns, current economic trends and changes in customer demand and acceptance of its products. The Company expenses shipping and handling costs as incurred and includes them in the cost of revenues. When the Company bills shipping and handling costs to customers, such amounts billed are included as a component of revenue.
Cost of Goods and Service [Policy Text Block]	Cost of Revenues Cost of revenues consists primarily of manufacturing overhead costs, material costs and direct labor. A significant portion of the Company's cost of revenues currently consists of manufacturing overhead costs. These overhead costs include the cost of quality assurance, material procurement, inventory control, facilities, equipment and operations supervision and management. Cost of revenues also includes depreciation expense for the Lightboxes under lease and evaluation agreements, product warranty costs, product written-off due to excess or obsolescence, and certain direct costs such as shipping costs.
Standard Product Warranty, Policy [Policy Text Block]	Product Warranty Costs The Company typically offers a one Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 Beginning balance $ 221 $ 206 $ 215 $ 272 Warranty provision 50 34 111 36 Usage/Release (50 ) (25 ) (105 ) (93 ) Ending balance $ 221 $ 215 $ 221 $ 215
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 attributable 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 attributable to common stockholder 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 June 30, 2020 2019, no Net loss per share attributable to common stockholders was determined as follows (in thousands, except per share data): Three Months Ended June 30, Six Months Ended June 30, 20 20 201 9 20 20 201 9 Net loss attributable to common stockholders $ (4,967 ) $ (5,546 ) $ (11,785 ) $ (11,496 ) Weighted average common stock outstanding, basic and diluted 27,310 6,377 20,963 5,319 Net loss per share attributable to common stockholders, basic and diluted $ (0.18 ) $ (0.87 ) $ (0.56 ) $ (2.16 ) 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 June 30, Six Months Ended June 30, 20 20 201 9 20 20 2019 Common stock warrants equivalents 2,753,999 2,801,606 2,753,999 3,645,862 Common stock options 7,133 7,492 7,200 7,673 Convertible preferred stock 48,503 44,923 48,503 45,109 Unvested restricted stock units 839,804 287,817 856,749 288,581 3,649,439 3,141,838 3,666,451 3,987,225
Segment Reporting, Policy [Policy Text Block]	Segment and Geographical Information The Company operates and manages its business as one three June 30, 2020 2019, 93% 92%, six June 30, 2020 2019, 96% 92%,
New Accounting Pronouncements, Policy [Policy Text Block]	Recent Accounting Pronouncements Recently adopted accounting standards In June 2016, 2016 13, Financial Instruments – Credit Losses first 2020. not Recent accounting standards not In December 2019, 2019 12, Income Taxes (Topic 740 first 2021 not

Note 2 - Summary of Significa_2

Note 2 - Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2020
Notes Tables
Schedule of Product Warranty Liability [Table Text Block]	Three Months Ended June 30, Six Months Ended June 30, 2020 2019 2020 2019 Beginning balance $ 221 $ 206 $ 215 $ 272 Warranty provision 50 34 111 36 Usage/Release (50 ) (25 ) (105 ) (93 ) Ending balance $ 221 $ 215 $ 221 $ 215
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	Three Months Ended June 30, Six Months Ended June 30, 20 20 201 9 20 20 201 9 Net loss attributable to common stockholders $ (4,967 ) $ (5,546 ) $ (11,785 ) $ (11,496 ) Weighted average common stock outstanding, basic and diluted 27,310 6,377 20,963 5,319 Net loss per share attributable to common stockholders, basic and diluted $ (0.18 ) $ (0.87 ) $ (0.56 ) $ (2.16 )
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	Three Months Ended June 30, Six Months Ended June 30, 20 20 201 9 20 20 2019 Common stock warrants equivalents 2,753,999 2,801,606 2,753,999 3,645,862 Common stock options 7,133 7,492 7,200 7,673 Convertible preferred stock 48,503 44,923 48,503 45,109 Unvested restricted stock units 839,804 287,817 856,749 288,581 3,649,439 3,141,838 3,666,451 3,987,225

Note 4 - Inventories (Tables)

Note 4 - Inventories (Tables)	6 Months Ended
	Jun. 30, 2020
Notes Tables
Schedule of Inventory, Current [Table Text Block]	June 30, December 31, 20 20 201 9 Raw materials $ 2,040 $ 1,426 Work-in-process 402 596 Finished products 1,715 1,890 Total inventories $ 4,157 $ 3,912

Note 5 - Borrowings (Tables)

Note 5 - Borrowings (Tables)	6 Months Ended
	Jun. 30, 2020
Notes Tables
Schedule of Debt [Table Text Block]	Year Ending December 31, 2020 (remaining six months of the year) $ — 2021 3,400 2022 6,266 2023 4,518 14,184 Less: Amount of PIK additions and final facility fee to be accreted subsequent to June 30, 2020 (3,905 ) Less: Amount representing debt financing costs (503 ) Borrowings, as of June 30, 2020 $ 9,776 Year Ending December 31, 2020 (remaining six months of the year) $ 264 2021 1,575 2022 521 2,360 Less: Amount of interest to be accreted subsequent to June 30, 2020 (27 ) Borrowings, as of June 30, 2020 $ 2,333

Note 6 - Commitments and Cont_2

Note 6 - Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2020
Notes Tables
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	Year Ending December 31, 2020 (remaining six months of the year) $ 544 2021 1,123 2022 1,162 2023 1,203 2024 1,138 5,170 Less: Imputed interest (702 ) Leasehold liability as of June 30, 2020 $ 4,468

Note 7 - Stockholders' Equity (

Note 7 - Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2020
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 February 2018 financing 8,979,000 897,900 $ 20.00 February 2025 Series 2 Warrants issued in February 2018 financing 8,709,500 870,950 $ 20.00 February 2025 Warrants issued in July 2018 financing 1,083,091 108,309 $ 15.80 July 2021 Warrants issued in November 2018 financing 8,768,395 876,840 $ 4.00 November 2023 Total 27,539,986 2,753,999
Share-based Payment Arrangement, Option, Activity [Table Text Block]	Number of (in thousands) Weighted Average Price Weighted Average Remaining Contractual Life (in years) Intri n sic Value (in thousands) Balance at December 31, 2019 7,401 $ 1,309.47 6.81 $ — Granted — $ — Exercised — $ — Expired (23 ) $ 820.00 Forfeited (297 ) $ 1,705.58 Balance at June 30, 2020 7,081 $ 1,291.74 6.10 $ — Exercisable at June 30, 2020 7,004 $ 1,296.85 6.09 $ — Vested and expected to vest at June 30, 2020 7,081 $ 1,291.74 6.10 $ —
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, 2019 908,504 $ 4.09 1.81 Awarded 47,500 $ 0.58 — Released (2,755 ) $ 72.65 — Forfeited (138,062 ) $ 3.04 — Awards outstanding at June 30, 2020 815,187 $ 3.83 1.41

Note 8 - Stock-based Compensa_2

Note 8 - Stock-based Compensation (Tables)	6 Months Ended
	Jun. 30, 2020
Notes Tables
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]	Three Months Ended June 30, Six Months Ended June 30, 20 20 201 9 20 20 201 9 Cost of revenues $ 27 $ 40 $ 61 $ 87 Research and development expenses 106 116 238 218 Selling, general and administrative expenses 192 360 477 704 $ 325 $ 516 $ 776 $ 1,009

Note 1 - Organization (Details

Note 1 - Organization (Details Textual) - USD ($)

Jul. 09, 2020

Jun. 26, 2020

May 06, 2020

Apr. 30, 2020

Apr. 23, 2020

Jan. 31, 2020

Aug. 26, 2019

Feb. 16, 2018

Jul. 31, 2020

May 31, 2020

May 31, 2019

Jun. 30, 2020

Dec. 31, 2019

Jun. 30, 2019

Dec. 31, 2018

Retained Earnings (Accumulated Deficit), Ending Balance

$ (358,186,000)

$ (348,335,000)

Cash and Cash Equivalents, at Carrying Value, Ending Balance

$ 16,550,000

$ 10,943,000

$ 14,754,000

$ 16,410,000

Proceeds from Issuance or Sale of Equity, Net

$ 15,500,000

COVID 19 [Member]

Reduction of Non-manufacturing Employees Salaries

20.00%

Reduction of Hours Worked by Manufacturing Workers, Percentage

20.00%

Paycheck Protection Program CARES Act [Member]

Proceeds from Issuance of Long-term Debt, Total

$ 2,300,000

June and July 2020 Public Offering [Member]

Proceeds from Issuance or Sale of Equity, Net

$ 5,500,000

Stock Issued During Period, Shares, New Issues (in shares)

20,000,000

Share Price (in dollars per share)

$ 0.27

June and July 2020 Public Offering [Member] | Subsequent Event [Member]

Proceeds from Issuance or Sale of Equity, Net

$ 5,500,000

Stock Issued During Period, Shares, New Issues (in shares)

3,000,000

April and May 2020 Public Offering [Member]

Proceeds from Issuance or Sale of Equity, Net

$ 3,000,000

$ 3,000,000

Stock Issued During Period, Shares, New Issues (in shares)

1,890,000

12,600,000

Share Price (in dollars per share)

$ 0.25

August Public Offering [Member]

Proceeds from Issuance or Sale of Equity, Net

$ 3,900,000

$ 3,800,000

Stock Issued During Period, Shares, New Issues (in shares)

3,813,559

Share Price (in dollars per share)

$ 1.18

January 2020 Public Offering [Member]

Proceeds from Issuance or Sale of Equity, Net

$ 3,900,000

$ 3,800,000

Stock Issued During Period, Shares, New Issues (in shares)

6,428,572

Share Price (in dollars per share)

$ 0.70

April and May Offering [Member]

Proceeds from Issuance or Sale of Equity, Net

$ 8,000,000

Note 2 - Summary of Significa_3

Note 2 - Summary of Significant Accounting Policies (Details Textual) shares in Thousands, $ in Thousands	Jun. 19, 2019	Jun. 30, 2020USD ($)	Jun. 30, 2019	Jun. 30, 2020USD ($)shares	Jun. 30, 2019shares	Dec. 31, 2019USD ($)
Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax, Total | $		$ 0		$ 0		$ 0
Warranty Period (Year)				1 year
Weighted Average Number of Shares, Common Stock Subject to Repurchase or Cancellation (in shares) | shares				0	0
Number of Reportable Segments				1
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | UNITED STATES
Concentration Risk, Percentage		93.00%	92.00%	96.00%	92.00%
Reverse Stock Split [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	10

Note 2 - Summary of Significa_4

Note 2 - Summary of Significant Accounting Policies - Product Warranty (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Beginning balance	$ 221	$ 206	$ 215	$ 272
Warranty provision	50	34	111	36
Usage/Release	(50)	(25)	(105)	(93)
Ending balance	$ 221	$ 215	$ 221	$ 215

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		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Net loss attributable to common stockholders	$ (4,967)	$ (5,546)	$ (11,785)	$ (11,496)
Weighted average common stock outstanding, basic and diluted (in shares)	27,310	6,377	20,963	5,319
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.18)	$ (0.87)	$ (0.56)	$ (2.16)

Note 2 - Summary of Significa_6

Note 2 - Summary of Significant Accounting Policies - Anti-dilutive Securities (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Antidilutive Securities (in shares)	3,649,439	3,141,838	3,666,451	3,987,225
Common Stock Warrants [Member]
Antidilutive Securities (in shares)	2,753,999	2,801,606	2,753,999	3,645,862
Common Stock Options [ member]
Antidilutive Securities (in shares)	7,133	7,492	7,200	7,673
Preferred Stock [Member]
Antidilutive Securities (in shares)	48,503	44,923	48,503	45,109
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities (in shares)	839,804	287,817	856,749	288,581

Note 3 - Fair Value Measureme_2

Note 3 - Fair Value Measurements (Details Textual) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Fair Value, Inputs, Level 2 [Member]
Assets, Fair Value Disclosure	$ 0	$ 0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 3 [Member]
Assets, Fair Value Disclosure	0	0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 0	$ 0

Note 4 - Inventories - Schedule

Note 4 - Inventories - Schedule of Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Raw materials	$ 2,040	$ 1,426
Work-in-process	402	596
Finished products	1,715	1,890
Total inventories	$ 4,157	$ 3,912

Note 5 - Borrowings (Details Te

Note 5 - Borrowings (Details Textual)	Apr. 23, 2020USD ($)	Feb. 14, 2018USD ($)	Jun. 30, 2020USD ($)	Jun. 30, 2019USD ($)	Dec. 31, 2021USD ($)	Jun. 30, 2020USD ($)	Jun. 30, 2019USD ($)	Dec. 31, 2023USD ($)	Dec. 31, 2022USD ($)	Mar. 02, 2020USD ($)	Dec. 31, 2019USD ($)	Jun. 15, 2016USD ($)	Sep. 22, 2015USD ($)
Line of Credit Facility, Maximum Borrowing Capacity													$ 50,000,000
Debt Instrument, Covenant Compliance Target Minimum Revenue, Next Twelve Months										$ 10,000,000
Debt Instrument, Covenant, Compliance Target Minimum Revenue Second Year										12,000,000
Debt Instrument, Covenant Compliance Target Minimum Revenue Third Year										$ 15,000,000
Debt Instrument, Redemption Initial Prepayment Premium Percentage													5.00%
Debt Instrument, Redemption Annual Decline in Prepayment Premium Percentage													1.00%
Debt Instrument, Redemption Prepayment Premium Percentage after Fifth Year													0.00%
Debt Instrument, Financing Fee Percentage													1.50%
Debt Instrument, Final Facility Fee Percentage													15.00%
Debt Instrument, Covenant Compliance Cash and Certain Cash Equivalents Minimum													$ 3,500,000
Debt Instrument, Covenant Compliance Prepayment Multiplier for Revenue Shortfall													2
Paycheck Protection Program CARES Act [Member]
Interest Expense, Debt, Total			$ 4,000			$ 4,000
Proceeds from Issuance of Long-term Debt, Total	$ 2,300,000
CRG [Member]
Interest Expense, Debt, Total			410,000	$ 364,000		808,000	$ 714,000
CRG [Member] | Loan Agreement [Member]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Total			503,000			503,000					$ 588,000		$ 1,300,000
Amortization of Debt Discount (Premium)			$ 42,000	$ 43,000		$ 84,000	$ 86,000
CRG [Member] | Loan Agreement [Member] | Forecast [Member]
Debt Instrument, Periodic Payment, Principal					$ 1,400,000
Debt Instrument, Periodic Payment, Total					$ 2,700,000			$ 2,700,000	$ 5,500,000
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
Debt Instrument, Interest Rate, Stated Percentage													12.50%
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

Note 5 - Borrowings - Schedule

Note 5 - Borrowings - Schedule of Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
2020 (remaining six months of the year)	$ 544
Borrowings, as of June 30, 2020	10,808	$ 8,967
Paycheck Protection Program CARES Act [Member]
2020 (remaining six months of the year)	264
2021	1,575
2022	521
Long-term Debt, Total	2,360
Borrowings, as of June 30, 2020	2,333
Less: Amount of interest to be accreted subsequent to June 30, 2020	(27)
CRG [Member] | Loan Agreement [Member]
2020 (remaining six months of the year)
2021	3,400
2022	6,266
2023	4,518
Long-term Debt, Total	14,184
Less: Amount of PIK additions and final facility fee to be accreted subsequent to June 30, 2020	(3,905)
Less: Amount representing debt financing costs	(503)
Borrowings, as of June 30, 2020	$ 9,776

Note 6 - Commitments and Cont_3

Note 6 - Commitments and Contingencies (Details Textual) - USD ($)	Dec. 01, 2017	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Apr. 01, 2019	Jan. 01, 2019
Operating Lease, Right-of-Use Asset		$ 4,468,000		$ 4,468,000		$ 4,856,000	$ 6,000,000
Lessee, Operating Lease, Term of Contract (Year)							5 years
Lessee, Operating Lease, Liability, Payments, Due, Total		5,170,000		5,170,000			$ 5,800,000
Lessee, Operating Lease, Discount Rate							6.50%
Operating Lease, Expense, Excluding Maintenance Fee and Other Expense, Monthly		105,000
Operating Lease, Expense		314,000	$ 314,000	628,000	$ 806,000
Operating Lease, Right-of-Use Asset, Amortization Expense		239,000	$ 219,000	475,000	$ 219,000
Prepaid Rent		375,000		375,000
Purchase Commitment [Member]
Purchase Obligation, Total		$ 1,000,000		$ 1,000,000
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset								$ 1,800,000
Facility Sublease [Member]
Operating Leases Sublease Expiration Prior to Base Lease (Day)	15 days
Operating Leases, Monthly Minimum Sublease Rental Payments Receivable Final	$ 82,410

Note 6 - Commitments and Cont_4

Note 6 - Commitments and Contingencies - Future Operating Lease Payments (Details) - USD ($)	Jun. 30, 2020	Apr. 01, 2019
2020 (remaining six months of the year)	$ 544,000
2021	1,123,000
2022	1,162,000
2023	1,203,000
2024	1,138,000
Lessee, Operating Lease, Liability, to be Paid, Total	5,170,000	$ 5,800,000
Less: Imputed interest	(702,000)
Leasehold liability as of June 30, 2020	$ 4,468,000

Note 7 - Stockholders' Equity_2

Note 7 - Stockholders' Equity (Details Textual) - USD ($)	Jun. 19, 2019	Nov. 01, 2018	Jul. 13, 2018	Feb. 16, 2018	Feb. 14, 2018	Dec. 31, 2019	Jan. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Mar. 10, 2020	Aug. 28, 2019	Aug. 22, 2018	Jan. 31, 2015
Preferred Stock, Shares Authorized (in shares)						5,000,000		5,000,000		5,000,000		5,000,000
Preferred Stock, Par or Stated Value Per Share (in dollars per share)						$ 0.001		$ 0.001		$ 0.001		$ 0.001
Preferred Stock, Shares Issued, Total (in shares)						48,503		48,503		48,503		48,503
Preferred Stock, Shares Outstanding, Ending Balance (in shares)						48,503		48,503		48,503		48,503
Proceeds from Issuance or Sale of Equity, Net				$ 15,500,000
Common Stock, Shares Authorized (in shares)						100,000,000		100,000,000		100,000,000		100,000,000
Common Stock, Par or Stated Value Per Share (in dollars per share)						$ 0.001		$ 0.001		$ 0.001		$ 0.001
Common Stock, Shares, Issued, Total (in shares)						10,364,663		51,339,024		51,339,024		10,364,663
Common Stock, Shares, Outstanding, Ending Balance (in shares)						10,364,663		51,339,024		51,339,024		10,364,663
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						2,753,999		2,753,999		2,753,999		2,753,999
Proceeds from Warrant Exercises											$ 7,993,000
Class of Warrant or Right, Outstanding (in shares)								27,539,986		27,539,986
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)										4 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)										10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)										0	0
Share-based Payment Arrangement, Expense, Tax Benefit								$ 0	$ 0	$ 0	$ 0
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total								20,000		$ 20,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)										255 days
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total								$ 1,900,000		$ 1,900,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)										1 year 146 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)						908,504		815,187		815,187		908,504
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Fair Value								$ 300,000		$ 300,000
Share Price (in dollars per share)								$ 0.31		$ 0.31
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value										$ 1,200	$ 565
Minimum [Member] | Common Stock Options [ member]
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent										100.00%
Minimum [Member] | Common Stock Options [ member] | Stockholder with More than 10% Voting Power [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent										110.00%
Minimum [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)										3 years
Maximum [Member] | Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)										4 years
The 2015 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)																	3,300
Share-based Compensation Arrangement by Share-based Payment Award, Additional Shares Reserved for Issuance, Annual (in shares)																	4,225
Share-based Compensation Arrangement by Share-based Payment Award, Additional Shares Reserved for Issuance, Percentage on Shares Outstanding																	5.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in shares)	800,000												300,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)								187,753		187,753
Officer and Director Share Purchase Plan [Member]
Common Stock, Shares, Issued, Total (in shares)								53,034		53,034
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)														125,000	40,000	20,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)								92,170		92,170
Common Stock Warrants, Issued with Series E Convertible Preferred Stock [Member]
Class of Warrant or Right, Securities Called as Percentage of Convertible Preferred Stock Shares																	50.00%
Common Stock Warrants, Issued with Series B Preferred Stock [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)				1,797,900				1,768,850		1,768,850
Common Stock Warrants, Issued with Series B Preferred Stock, Warrant One [Member]
Class of Warrant or Right, Number of Warrants Issued for Each Share of Preferred Stock (in shares)				1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)				$ 4
Class of Warrant or Right, Contingent Expiration Period Following Initial Exercise Date (Year)				7 years
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)				50
Common Stock Warrants, Issued with Series B Preferred Stock, Warrant Two [Member]
Class of Warrant or Right, Number of Warrants Issued for Each Share of Preferred Stock (in shares)				1
Class of Warrant or Right, Contingent Expiration Period Following Initial Exercise Date (Year)				7 years
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)				50
Class of Warrant or Right, Expiration Period Following FDA Clearance (Day)				60 days
Common Stock Warrants [Member] | Placement Agency Sale - Prospectus Supplement of July 12, 2018 [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			108,309
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 15.80
Common Stock Warrants [Member] | November Public Offering [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)		2,875,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)		$ 4
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)		1
Class of Warrant or Right, Exercised (in shares)												1,998,079
Proceeds from Warrant Exercises												$ 8,000,000
Class of Warrant or Right, Outstanding (in shares)						876,840		876,840		876,840		876,840
Preferred Stock Warrants [Member] | November Public Offering [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)		250
Common Stock [Member]
Stock Issued During Period, Shares, New Issues (in shares)		728,500
Common Stock [Member] | Placement Agency Sale - Prospectus Supplement of July 12, 2018 [Member]
Stock Issued During Period, Shares, New Issues (in shares)			216,618
Common Stock [Member] | November Public Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)		728,500
Conversion of Series B Preferred Stock into Common Stock [Member]
Conversion of Stock, Shares Converted (in shares)												1,523
Conversion of Stock, Shares Issued (in shares)												380,750
Conversion of Series C Preferred Stock into Common Stock [Member]
Conversion of Stock, Shares Issued (in shares)											542,500
Series A Preferred Stock [Member]
Preferred Stock, Shares Outstanding, Ending Balance (in shares)								48,325		48,325
Dividends, Preferred Stock, Total								$ 967,000	$ 895,000	$ 1,900,000	$ 1,800,000
Series A Preferred Stock [Member] | CRG [Member]
Preferred Stock Dividends, Shares (in shares)						3,580	2,945
Series B Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share (in dollars per share)				$ 0.001
Preferred Stock, Shares Outstanding, Ending Balance (in shares)						178		178		178		178
Stock Issued During Period, Shares, New Issues (in shares)				17,979
Preferred Stock, Convertible, Conversion Price (in dollars per share)										$ 0.25		$ 0.25
Series C Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.001
Preferred Stock, Shares Outstanding, Ending Balance (in shares)									2,170		2,170
Stock Issued During Period, Shares, New Issues (in shares)		8,586
Proceeds from Issuance or Sale of Equity, Net		$ 10,200,000
Conversion of Principal Amount of Senior Secured Loan to Newly Authorized Series A Preferred Stock [Member] | Series A Preferred Stock [Member]
Convertible Preferred Stock, Shares of Common Stock Issuable on Conversion (in shares)					2,090,000
Preferred Stock, Dividend Rate, Percentage					8.00%
CRG [Member] | Conversion of Principal Amount of Senior Secured Loan to Newly Authorized Series A Preferred Stock [Member]
Debt Conversion, Original Debt, Amount					$ 38,000,000
Debt Conversion, Fees and Prepayment Premium Amount					3,800,000
Debt Conversion, Converted Instrument, Amount					$ 41,800,000

Note 7 - Stockholder's Equity -

Note 7 - Stockholder's Equity - Outstanding Warrants (Details) - $ / shares	Jun. 30, 2020	Dec. 31, 2019
Total outstanding and exercisable (in shares)	27,539,986
Underlying shares of common stock (in shares)	2,753,999	2,753,999
Series 1 February 2018 Warrants [Member]
Total outstanding and exercisable (in shares)	8,979,000
Underlying shares of common stock (in shares)	897,900
Exercise price per share (in dollars per share)	$ 20
Series 2 February 2018 Warrants [Member]
Total outstanding and exercisable (in shares)	8,709,500
Underlying shares of common stock (in shares)	870,950
Exercise price per share (in dollars per share)	$ 20
November 2018 Warrants [Member]
Total outstanding and exercisable (in shares)	1,083,091
Underlying shares of common stock (in shares)	108,309
Exercise price per share (in dollars per share)	$ 15.80
July 2018 Warrants [Member]
Total outstanding and exercisable (in shares)	8,768,395
Underlying shares of common stock (in shares)	876,840
Exercise price per share (in dollars per share)	$ 4

Note 7 - Stockholders' Equity -

Note 7 - Stockholders' Equity - Stock Option Activity (Details) - $ / shares shares in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Options (in shares)	7,401
Options, weighted average exercise price (in dollars per share)	$ 1,309.47
Balance, weighted average remaining contractual life (Year)	6 years 36 days	6 years 295 days
Expired (in shares)	(23)
Expired, weighted average exercise price (in dollars per share)	$ 820
Forfeited (in shares)	(297)
Forfeited, weighted average exercise price (in dollars per share)	$ 1,705.58
Options (in shares)	7,081	7,401
Options, weighted average exercise price (in dollars per share)	$ 1,291.74	$ 1,309.47
Exercisable (in shares)	7,004
Exercisable, weighted average exercise price (in dollars per share)	$ 1,296.85
Exercisable, weighted average remaining contractual life (Year)	6 years 32 days
Vested and expected to vest (in shares)	7,081
Vested and expected to vest, weighted average exercise price (in dollars per share)	$ 1,291.74
Vested and expected to vest, weighted average remaining contractual life (Year)	6 years 36 days

Note 7 - Stockholders' Equity_3

Note 7 - Stockholders' Equity - Restricted Stock Units Award Activity (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Awards outstanding, Shares (in shares)	908,504
Awards outstanding, Weighted grant date fair value (in dollars per share)	$ 4.09
Awards outstanding, Weighted average remaining contractual term (Year)	1 year 149 days	1 year 295 days
Awarded, Shares (in shares)	47,500
Awarded, Weighted grant date fair value (in dollars per share)	$ 0.58
Released, Shares (in shares)	(2,755)
Released, Weighted grant date fair value (in dollars per share)	$ 72.65
Forfeited, Shares (in shares)	(138,062)
Forfeited, Weighted grant date fair value (in dollars per share)	$ 3.04
Awards outstanding, Shares (in shares)	815,187	908,504
Awards outstanding, Weighted grant date fair value (in dollars per share)	$ 3.83	$ 4.09

Note 8 - Stock-based Compensa_3

Note 8 - Stock-based Compensation - Noncash Stock-based Compensation Expense Related to Stock Options, ESPP, and RSUs (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Allocated Share-based Compensation Expense	$ 325	$ 516	$ 776	$ 1,009
Cost of Sales [Member]
Allocated Share-based Compensation Expense	27	40	61	87
Research and Development Expense [Member]
Allocated Share-based Compensation Expense	106	116	238	218
Selling, General and Administrative Expenses [Member]
Allocated Share-based Compensation Expense	$ 192	$ 360	$ 477	$ 704