Pulse Biosciences (PLSE) 10-Q 13 Nov 23 2023 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2023	Oct. 31, 2023
Document Information [Line Items]
Entity Central Index Key	0001625101
Entity Registrant Name	Pulse Biosciences, Inc.
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2023
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	001-34899
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-5696597
Entity Address, Address Line One	3957 Point Eden Way
Entity Address, City or Town	Hayward
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94545
City Area Code	510
Local Phone Number	906-4600
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	PLSE
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		54,991,487

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 50,386	$ 61,139
Prepaid expenses and other current assets	1,237	1,008
Total current assets	51,623	62,147
Property and equipment, net	1,648	1,961
Intangible assets, net	2,052	2,551
Goodwill	2,791	2,791
Right-of-use assets	7,466	8,062
Other assets	365	365
Total assets	65,945	77,877
Current liabilities:
Accounts payable	1,412	1,573
Accrued expenses	3,004	2,595
Lease liability, current	1,016	896
Related party note payable, current	0	917
Total current liabilities	5,432	5,981
Lease liability, less current portion	8,368	9,144
Related party note payable, less current	0	65,000
Total liabilities	13,800	80,125
Commitments and contingencies (Note 8)
Stockholders’ equity:
Preferred stock, $0.001 par value; authorized – 50,000 shares; no shares issued and outstanding	0	0
Common stock, $0.001 par value; authorized – 500,000 shares; issued and outstanding – 54,991 shares and 37,235 shares at September 30, 2023 and December 31, 2022 respectively	55	37
Additional paid-in capital	377,072	292,420
Accumulated other comprehensive income (loss)	0	0
Accumulated deficit	(324,982)	(294,705)
Total stockholders’ equity (deficit)	52,145	(2,248)
Total liabilities and stockholders’ equity	$ 65,945	$ 77,877

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares shares in Thousands	Sep. 30, 2023	Dec. 31, 2022
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	50,000	50,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	500,000	500,000
Common stock, shares issued (in shares)	54,991	37,235
Common stock, shares outstanding (in shares)	54,991	37,235

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenues:
Total revenues	$ 0	$ 0	$ 0	$ 709
Cost and expenses:
Cost of revenues	0	8,400	0	10,653
Research and development	7,472	4,517	19,998	16,744
Sales and marketing	0	2,020	0	11,251
General and administrative	3,780	3,088	11,043	11,373
Total cost and expenses	11,252	18,025	31,041	50,021
Loss from operations	(11,252)	(18,025)	(31,041)	(49,312)
Other income (expense):
Interest income (expense), net	686	(14)	764	4
Total other income (expense)	686	(14)	764	4
Loss from operations, before income taxes	(10,566)	(18,039)	(30,277)	(49,308)
Income tax benefit	0	0	0	0
Net loss	(10,566)	(18,039)	(30,277)	(49,308)
Other comprehensive gain (loss):
Unrealized gain (loss) on available-for-sale securities	0	0	0	0
Comprehensive loss	$ (10,566)	$ (18,039)	$ (30,277)	$ (49,308)
Net loss per share:
Basic and diluted net loss per share (in dollars per share)	$ (0.19)	$ (0.49)	$ (0.66)	$ (1.5)
Weighted average shares used to compute net loss per common share — basic and diluted (in shares)	54,923	37,158	45,672	32,825

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net loss	$ (30,277)	$ (49,308)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	404	520
Amortization of intangible assets	499	499
Stock-based compensation	3,837	4,443
Write-off of excessive and obsolete inventory	0	7,371
Changes in operating assets and liabilities:
Accounts receivable	0	56
Inventory	0	(2,297)
Prepaid expenses and other current assets	(343)	940
Other receivables	114	(53)
Right-of-use assets	596	535
Accounts payable	(174)	(895)
Accrued expenses	409	(407)
Deferred revenue	0	22
Lease liabilities	(656)	(573)
Accrued interest on related party note payable	(668)	98
Accrued interest on note payable	0	1
Net cash used in operating activities	(26,259)	(39,048)
Cash flows from investing activities:
Purchases of property and equipment	(78)	(360)
Net cash used in investing activities	(78)	(360)
Cash flows from financing activities:
Proceeds from issuance of common stock under employee stock purchase plan	395	485
Proceeds from issuance of common stock	0	14,893
Proceeds from exercises of warrants	14,828	15
Proceeds from exercises of stock options	367	0
Proceeds from issuance of related party note	0	65,000
Payments made on insurance loan agreement	0	(437)
Issuance cost in relation to related party note extinguishment	(6)	0
Net cash provided by financing activities	15,584	79,956
Net (decrease) increase in cash and cash equivalents	(10,753)	40,548
Cash and cash equivalents at beginning of period	61,139	28,614
Cash and cash equivalents at end of period	50,386	69,162
Supplemental disclosure of noncash investing and financing activities:
Equipment purchases included in accounts payable and accrued expenses	13	(16)
Principal and accrued interest of related party note settled via issuance of common stock	65,249	0
Issuance costs in accounts payable and accrued expenses	$ 0	$ (29)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Private Placement [Member] Common Stock [Member]	Private Placement [Member] Additional Paid-in Capital [Member]	Private Placement [Member] AOCI Attributable to Parent [Member]	Private Placement [Member] Retained Earnings [Member]	Private Placement [Member]	Rights Offering [Member] Common Stock [Member]	Rights Offering [Member] Additional Paid-in Capital [Member]	Rights Offering [Member] AOCI Attributable to Parent [Member]	Rights Offering [Member] Retained Earnings [Member]	Rights Offering [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2021											29,716
Balance at Dec. 31, 2021											$ 29	$ 271,861	$ 0	$ (236,200)	$ 35,690
Issuance of common stock under employee stock purchase plan (in shares)											188
Issuance of common stock under employee stock purchase plan											$ 1	485	0	0	486
Stock-based compensation expense											0	4,443	0	0	4,443
Net loss											$ 0		0	(49,308)	(49,308)
Issuance of common stock pursuant to warrant exercise (in shares)											7
Issuance of common stock pursuant to warrant exercise											$ 0	14	0	0	14
Issuance of shares in Rights Offering, net of issuance costs of $136 (in shares)						7,317
Issuance of shares in Rights Offering, net of issuance costs of $136						$ 7	$ 14,857	$ 0	$ 0	$ 14,864
Balance (in shares) at Sep. 30, 2022											37,228
Balance at Sep. 30, 2022											$ 37	291,660	0	(285,508)	6,189
Balance (in shares) at Jun. 30, 2022											37,126
Balance at Jun. 30, 2022											$ 37	290,847	0	(267,469)	23,415
Issuance of common stock under employee stock purchase plan (in shares)											102
Issuance of common stock under employee stock purchase plan											$ 0	113	0	0	113
Stock-based compensation expense											0	723	0	0	723
Net loss											$ 0		0	(18,039)	(18,039)
Issuance of common stock pursuant to warrant exercise (in shares)											0
Issuance of common stock pursuant to warrant exercise											$ 0	2	0	0	2
Rights offering, additional issuance costs											$ 0	(25)	0	0	(25)
Balance (in shares) at Sep. 30, 2022											37,228
Balance at Sep. 30, 2022											$ 37	291,660	0	(285,508)	6,189
Balance (in shares) at Dec. 31, 2022											37,235
Balance at Dec. 31, 2022											$ 37	292,420	0	(294,705)	(2,248)
Issuance of common stock upon exercise of stock options (in shares)											148
Issuance of common stock upon exercise of stock options											$ 0	367	0	0	367
Issuance of common stock under employee stock purchase plan (in shares)											347
Issuance of common stock under employee stock purchase plan											$ 1	394	0	0	395
Stock-based compensation expense											0	3,837	0	0	3,837
Net loss											$ 0	0	0	(30,277)	(30,277)
Issuance of common stock as part of debt extinguishment (in shares)	10,023
Issuance of common stock as part of debt extinguishment	$ 10	$ 65,233	$ 0	$ 0	$ 65,243
Issuance of common stock pursuant to warrant exercise (in shares)											7,238
Issuance of common stock pursuant to warrant exercise											$ 7	14,821	0	0	14,828
Balance (in shares) at Sep. 30, 2023											54,991
Balance at Sep. 30, 2023											$ 55	377,072	0	(324,982)	52,145
Balance (in shares) at Jun. 30, 2023											54,771
Balance at Jun. 30, 2023											$ 55	374,861	0	(314,416)	60,500
Issuance of common stock upon exercise of stock options (in shares)											135
Issuance of common stock upon exercise of stock options											$ 0	309	0	0	309
Issuance of common stock under employee stock purchase plan (in shares)											85
Issuance of common stock under employee stock purchase plan											$ 0	103	0	0	103
Warrant exercise, issuance cost adjustment											0	1	0	0	1
Stock-based compensation expense											0	1,798	0	0	1,798
Net loss											$ 0	0	0	(10,566)	(10,566)
Balance (in shares) at Sep. 30, 2023											54,991
Balance at Sep. 30, 2023											$ 55	$ 377,072	$ 0	$ (324,982)	$ 52,145

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (Parentheticals) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Private Placement [Member]
Issuance cost	$ 6
Rights Offering [Member]
Issuance cost		$ 136
Shares Issued Upon Warrants Exercised [Member]
Issuance cost	$ 9

Note 1 - Description of the Bus

Note 1 - Description of the Business	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	1. Pulse Biosciences, Inc. is a novel bioelectric medicine company committed to health innovation using its patented Nano-pulse Stimulation (“NPS”) technology, a revolutionary energy modality that delivers nanosecond-duration pulses of electrical energy, each less than a millionth of a second 2022 The Company was incorporated in Nevada on May 19, 2014. June 18, 2018, The Company’s activities are subject to significant risks and uncertainties, including the need for additional capital. The Company does not no no

Note 2 - Summary of Significant

Note 2 - Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Significant Accounting Policies [Text Block]	2. Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared on a basis consistent with the Company’s December 31, 2022 December 31, 2022 not 10 December 31, 2022 three nine September 30, 2023 not Principles of Consolidation The accompanying condensed consolidated financial statements include the financial statements of Pulse Biosciences, Inc. and its wholly-owned subsidiaries. Intercompany balances and transactions, if any, have been eliminated in consolidation. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires the Company to make estimates and assumptions that affect the amounts reported in the Financial Statements and accompanying notes to the condensed consolidated financial statements. Estimates include, but are not Significant Accounting Policies The Company’s significant accounting policies are described in the Company’s Annual Report on Form 10 December 31, 2022 nine September 30, 2023, Stock-Based Compensation The Company's stock-based compensation programs include stock options and an employee stock purchase program. The Company accounts for stock-based compensation using the fair value method. The Company periodically issues stock options to officers, directors, employees, and consultants for services rendered. Such issuances vest and expire according to terms established at the issuance date. Stock-based payments to officers, directors and employees, including grants of employee stock options, are recognized in the financial statements based on their grant date fair values, which are estimated using the Black-Scholes option-pricing model. Stock-based compensation expense is charged to operations on a straight-line basis over the vesting period. The Company has granted stock options with both time-based as well as performance-based vesting conditions. For stock awards with performance-based vesting conditions, the Company does not may The Company has also issued certain stock options with market-based vesting conditions. These vesting conditions relate to the achievement of certain market capitalization targets of the Company. The grant date fair value for these stock options was determined using a Monte Carlo simulation. The expense is recognized over the requisite service period for each tranche of the awards. The requisite service period is the service period derived from the Monte Carlo simulation model. If the market capitalization targets are met sooner than the derived service period, the Company will accelerate the recognition of stock-based compensation expense to reflect the cumulative expense associated with the vested shares. The Monte Carlo simulation requires the Company to make assumptions and judgements about the variables used in the calculation including the expected term, volatility of the Company's common stock, an assumed risk-free interest rate, and cost of equity. The assumptions used in the option-pricing model represent management’s best estimates. If factors change and different assumptions are used, the Company's stock-based compensation expense could be materially different in the future. See Note 6 Valuation of Inventory Inventory is stated at lower of cost or net realizable value. The Company establishes the inventory basis by determining the cost based on standard costs approximating the purchase costs on a first first December 31, 2022, not Revenue from Contracts with Customers The Company recognized revenue at a point in time when it satisfied performance obligations by transferring control of promised goods to its customers. The amount of revenue recognized was equal to the consideration which the Company was entitled to in exchange for the promised goods, excluding any amounts assessed by government authorities for taxes which might have been collected from a customer. Sales contracts often involved the sale and delivery of multiple products, each of which typically represented a separate performance obligation in the contract. While the Company has sold these products on a stand-alone basis at their respective stand-alone selling prices (“SSP”), initial customer contracts primarily involved the bundling of products which were delivered concurrently to the customer. In such instances, the full consideration of the contract was recognized upon shipment of the products. The Company generally required receipt of full payment prior to shipment, however, from time to time, payment terms were extended to customers upon which the Company performed a necessary credit evaluation to ensure future collectability of the outstanding balance. The accounts receivable balance at September 30, 2023 zero not 10 Product Warranty The Company provides a standard warranty on eligible products which provides the customer assurances that the products comply with the agreed-upon specifications. The standard warranty does not may nine September 30, 2023, Warranty accrual activity consisted of the following for the three nine September 30, 2023 2022 Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Beginning balance $ — $ 122 $ 50 $ 80 Add: Accruals for warranties issued during the period — — — 42 Less: Adjustment for inventory at cost — (15 ) (50 ) (15 ) Ending balance $ — $ 107 $ — $ 107 Net Loss per Share The Company calculates basic net loss per share by dividing net loss by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share is computed by giving effect to all potential dilutive common stock equivalents outstanding during the period. For purposes of this calculation, options to purchase common stock and common stock warrants are considered common stock equivalents. Potential common shares that have an anti-dilutive effect (i.e., those that increase income per share or decrease loss per share) are excluded from the calculation of diluted net loss per share. Basic and diluted net loss per common share is the same for all periods presented because all warrants, stock options and restricted stock units outstanding are anti-dilutive. The following outstanding stock options, and warrants were excluded from the computation of diluted net loss per share for the periods presented because including them would have had an anti-dilutive effect: Nine Months Ended September 30, 2023 2022 Common stock warrants — 7,310,477 Common stock options 7,902,948 5,707,488 Total 7,902,948 13,017,965 Recent Accounting Pronouncements There are no

Note 3 - Fair Value of Financia

Note 3 - Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Fair Value Disclosures [Text Block]	3. The authoritative guidance with respect to fair value established a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three one three Level 1 1 Level 2 1, 2 Level 3 no not 3 The following table sets forth the fair value of the Company’s financial assets measured on a recurring basis as of September 30, 2023 December 31, 2022 September 30, 2023 Assets Classification Level 1 Level 2 Level 3 Total Money market funds Cash and cash equivalents $ 48,563 $ — $ — $ 48,563 Total assets measured at fair value $ 48,563 $ — $ — $ 48,563 December 31, 2022 Assets Classification Level 1 Level 2 Level 3 Total Money market funds Cash and cash equivalents $ 57,973 $ — $ — $ 57,973 Total assets measured at fair value $ 57,973 $ — $ — $ 57,973 The Company did not September 30, 2023 December 31, 2022

Note 4 - Balance Sheet Componen

Note 4 - Balance Sheet Components	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Supplemental Balance Sheet Disclosures [Text Block]	4. Property and Equipment, Net Property and equipment, net consisted of the following (in thousands): September 30, December 31, 2023 2022 Leasehold improvements $ 2,519 $ 2,519 Laboratory equipment 1,198 1,118 Furniture, fixtures and equipment 966 966 Software 296 289 Construction in progress 26 22 5,005 4,914 Less: Accumulated depreciation and amortization (3,357 ) (2,953 ) $ 1,648 $ 1,961 Depreciation expense was $0.1 million and $0.2 million for the three September 30, 2023 2022 nine September 30, 2023 2022 Intangible Assets, Net Intangible assets primarily consist of acquired licenses to utilize certain patents, know-how and technology relating to the Company’s NPS technology for biomedical applications acquired from Old Dominion University Research Foundation (“ODURF”), Eastern Virginia Medical School, and the University of Southern California. In addition, the Company entered into a Sponsored Research Agreement with Old Dominion University’s Frank Reidy Research Center for Bioelectrics, which includes certain intellectual property rights arising from the research. The Company is amortizing the intangible assets over an estimated useful life of 12 years. Intangible assets, net consisted of the following (in thousands): September 30, December 31, 2023 2022 Acquired patents and licenses $ 7,985 $ 7,985 Less: Accumulated amortization (5,933 ) (5,434 ) $ 2,052 $ 2,551 A schedule of the amortization of intangible assets for the remainder of 2023 three Years ending December 31: 2023 (remaining 3 months) $ 167 2024 665 2025 665 2026 555 $ 2,052 Accrued Expenses Accrued expenses consisted of the following (in thousands): September 30, December 31, 2023 2022 Compensation expense $ 2,255 $ 1,377 Director and officer liability insurance (Note 12) — 571 Clinical trial fees and costs 8 64 Professional fees 569 318 Warranty — 50 Other 172 215 $ 3,004 $ 2,595

Note 5 - Goodwill

Note 5 - Goodwill	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Goodwill Disclosure [Text Block]	5. In 2014, 805, Business Combinations In accordance with ASC Topic 350, Intangibles-Goodwill and Other 2017 04 not September 30, 2023 no

Note 6 - Stockholders' Equity a

Note 6 - Stockholders' Equity and Stock-based Compensation	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Share-Based Payment Arrangement [Text Block]	6. Equity and Stock-Based Compensation Private Placement Securities Purchase Agreement On April 30, 2023, May 9, 2023, 2022 8 Rights Offering On June 9, 2022, “2022 one one “2022 one 2022 2022 2022 May 2023, June 16, 2023, 2022 Common Stock Warrants 2022 Common Stock Warrants In connection with the 2022 2022 2022 not may not three May 10, 2023, May 9, 2023 June 16, 2023. September 30, 2023, 2022 Equity Plans 2017 2017 The Board of Directors of the Company (the “Board”) previously adopted, and the Company’s stockholders approved, the Company’s 2017 “2017 The 2017 may 2017 2015 “2015 not 2017 2017 January 1, 2023, 2017 2017 2017 December 31 September 30, 2023 2017 In November 2017, 2017 The Inducement Plan has a 10-year term and provides for the grant of equity-based awards, including nonstatutory stock options, restricted stock units, restricted stock, stock appreciation rights, performance shares and performance units, and its terms are substantially similar to the 2017 may ten first not May 2021, September 30, 2023 A summary of stock option activity under the 2015 2017 nine September 30, 2023 Stock Options Outstanding Number of shares Weighted average exercise price Weighted average remaining life (in years) Balances — December 31, 2022 5,250,696 $ 12.67 6.24 Options granted 3,475,886 5.78 Options exercised (148,367 ) 2.48 Options canceled (174,994 ) 6.55 Options expired (500,273 ) 12.69 Balances — September 30, 2023 7,902,948 $ 9.96 7.59 Exercisable — September 30, 2023 3,654,425 $ 14.11 5.59 Time-based Options The Company awards time-based options which vest and become exercisable, subject to the individual’s continued employment or service through the applicable vesting date. Time-based options can have various vesting schedules, most commonly new hire grants which generally vest 25% per year starting upon the first A summary of the time-based stock option activity under the 2015 2017 nine September 30, 2023 Stock Options Outstanding Number of shares Weighted average exercise price Weighted average remaining life (in years) Balances — December 31, 2022 4,730,394 $ 12.95 6.16 Options granted 527,886 6.05 Options exercised (148,367 ) 2.48 Options canceled (131,494 ) 8.00 Options expired (409,601 ) 12.99 Balances — September 30, 2023 4,568,818 $ 12.64 6.30 Exercisable — September 30, 2023 3,458,736 $ 14.27 5.53 The fair value of the time-based options granted during the nine September 30, 2023 Performance-based Options Certain stock options awarded by the Company contain performance conditions related to certain financial measures and achievements of strategic/operational milestones. The options will vest and become exercisable once the specific performance condition is fulfilled. A summary of the performance-based option activity under the 2017 nine September 30, 2023 Stock Options Outstanding Number of shares Weighted average exercise price Weighted average remaining life (in years) Balances — December 31, 2022 520,302 $ 10.08 7.02 Options granted 848,000 3.13 Options exercised — — Options canceled (43,500 ) 2.17 Options expired (90,672 ) 11.35 Balances — September 30, 2023 1,234,130 $ 5.49 8.81 Exercisable — September 30, 2023 195,689 $ 11.28 6.62 The fair value of the performance-based options granted during the nine September 30, 2023 Market-based Options Certain stock options awarded by the Company contain market conditions related to achievement of certain market capitalization targets. The options will vest and become exercisable once the specific market capitalization targets are fulfilled. A summary of the market-based option activity under the 2017 nine September 30, 2023 Stock Options Outstanding Number of shares Weighted average exercise price Weighted average remaining life (in years) Balances — December 31, 2022 — $ — — Options granted 2,100,000 6.78 Options exercised — — Options canceled — — Options expired — — Balances — September 30, 2023 2,100,000 $ 6.78 9.69 Exercisable — September 30, 2023 — — — The fair value of the market-based options granted during the nine September 30, 2023 The Company estimates the fair value of time-based and performance-based stock options on the grant date using the Black-Scholes option pricing model. The estimated fair value of these employee stock options is amortized on a straight-line basis over the requisite service period of the awards. The Company reviews, and when deemed appropriate, updates the assumptions used on a periodic basis. The fair value of time-based and performance-based stock options was estimated using the following weighted-average assumptions: Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Expected term in years 5.0 6.3 5.0 - 6.3 5.3 - 6.8 Expected volatility 93% 88% 89% - 94% 83% 88% Risk-free interest rate 3.7% 3.2% 3.7% 1.9% Dividend yield — — — — The Company estimates the fair value of market-based stock options on the grant date using a Monte Carlo simulation model. The estimated fair value of these employee stock options is amortized over the requisite service period for each tranche of the awards. The requisite service period is the service period derived from the Monte Carlo simulation model. If the market capitalization targets are met sooner than the derived service period, the Company will accelerate the recognition of stock-based compensation expense to reflect the cumulative expense associated with the vested shares. The fair value of market-based stock options was estimated using the following weighted-average assumptions: Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Expected term in years 4.0 - 6.3 — 4.0 - 6.3 — Expected volatility 90% — 90% — Risk-free interest rate 3.7% 3.8% — 3.4% 3.8% — Dividend yield — — — — 2017 The Board previously adopted, and the Company's stockholders approved, the Company’s 2017 “2017 The 2017 2017 2017 December 31 2022 2023 no 2017 three September 30, 2023, 2017 nine September 30, 2023, 2017 September 30, 2023 2017 The Company estimates the fair value of ESPP grants on their grant date using the Black-Scholes option pricing model. The estimated fair value of ESPP grants is amortized on a straight-line basis over the requisite service period of the grants. The Company reviews, and when deemed appropriate, updates the assumptions used on a periodic basis. The Company utilizes its estimated volatility in the Black-Scholes option pricing model to determine the fair value of ESPP grants. The fair value of ESPP grants was estimated using the following weighted-average assumptions: Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Expected term in years 0.5 - 1.0 0.5 - 1.0 0.5 - 1.0 0.5 - 1.0 Expected volatility 83% 83% 83% 83% Risk-free interest rate 5.4% - 5.5% 3.3% - 3.5% 5.1% - 5.5% 0.6% - 3.5% Dividend yield — — — — Stock-based Compensation Total stock-based compensation expense consisted of the following (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Cost of revenues $ — $ 24 $ — $ 204 Research and development 982 287 1,758 1,240 Sales and marketing — (44 ) — 772 General and administrative 816 456 2,079 2,227 Total stock-based compensation expense $ 1,798 $ 723 $ 3,837 $ 4,443 As of September 30, 2023 not Total stock-based compensation expense by type was as follows (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Time-based options $ 1,200 $ 562 $ 2,754 $ 3,814 Performance-based and market-based options 551 18 914 233 ESPP 47 143 169 396 Total stock-based compensation expense $ 1,798 $ 723 $ 3,837 $ 4,443

Note 7 - Research Grants and Ag

Note 7 - Research Grants and Agreements	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Research, Development, and Computer Software Disclosure [Text Block]	7. Sponsored Research Agreement The Company may March 2021, 12 May 2021, 12 may three nine September 30, 2023 not three nine September 30, 2022 September 30, 2023 not

Note 8 - Commitments and Contin

Note 8 - Commitments and Contingencies	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Commitments and Contingencies Disclosure [Text Block]	8. 2022 On September 20, 2022, “2022 January 1, 2023, March 20, 2024. March 17, 2023, no September 30, 2024. nine September 30, 2023 2022 April 30, 2023, 2022 April 30, 2023. May 9, 2023 2022 No 2022 Operating Leases In January 2017, five July 2017. In May 2019, 1 1” 2”, October 2029 1 2. The Company evaluated the lease amendment under the provisions of ASC 842. not 1 November 2019) 2 May 2020) Supplemental balance sheet information related to leases (in thousands): September 30, December 31, Assets: 2023 2022 Right-of-use assets $ 7,466 $ 8,062 September 30, December 31, Liabilities: 2023 2022 Current operating lease liabilities $ 1,016 $ 896 Non-current operating lease liabilities 8,368 9,144 Total lease liabilities $ 9,384 $ 10,040 Total cash paid for operating lease liabilities (in thousands): Nine Months Ended September 30, 2023 2022 Cash paid for operating lease liabilities $ 1,376 $ 1,353 Maturities of operating lease liabilities were as follows (in thousands): Year ending December 31: 2023 (remaining 3 months) $ 469 2024 1,910 2025 1,977 2026 2,046 2027 2,117 Thereafter 4,075 Total lease payments 12,594 Less imputed interest (3,210 ) Total lease liabilities $ 9,384 Weighted-average remaining lease term and discount rate, as of September 30, 2023 Weighted-average remaining lease term 6.09 Weighted-average discount rate 10 % Rent expense, including common area maintenance charges, was approximately $0.6 million and $0.5 million for the three September 30, 2023 2022 nine September 30, 2023 2022 Legal Proceedings From time to time, we may may In November 2022, not not March 2023, one not not not

Note 9 - Controlled Launch

Note 9 - Controlled Launch	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Controlled Launch [Text Block]	9. Controlled Launch In February 2021, 510 January 2021, June 2021 February 2021, June 2021, As part of the Controlled Launch, the Company selected 70 physicians and their practices to be the first As patient procedures and surveys were completed under the Controlled Launch program, the Company accrued the value of the credits earned, which were recorded in accrued expenses, with a corresponding charge to sales and marketing expense. The Company did not three nine September 30, 2023 three September 30, 2022 nine September 30, 2022 In September 2022, fourth 2022 During the nine September 30, 2023 not nine September 30, 2022 nine September 30, 2022 three September 30, 2022 10

Note 10 - Revenue

Note 10 - Revenue	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Revenue from Contract with Customer [Text Block]	10. In connection with its Controlled Launch program in dermatology, the Company recognized revenue at a point in time when it satisfied performance obligations by transferring control of promised goods to its customers. The amount of revenue recognized was equal to the consideration which the Company was entitled to in exchange for the promised goods, excluding any amounts assessed by government authorities for taxes which might be collected from a customer. This consideration may September 20, 2022, not three nine September 30, 2023 three September 30, 2022 nine September 30, 2022 Dermatology sales contracts, several which are still outstanding, often involved the sale and delivery of multiple performance obligations in the contract. Performance Obligations In the Controlled Launch, systems consisted of the CellFX console and its embedded software, handpieces, and disposable tips. The console was a physical piece of hardware used by the dermatology customer to perform patient procedures. Individually the console and software were not one Handpieces were attached to the console and used in conjunction with tips to perform patient procedures. Generally, in the Controlled Launch, upon initial sale of a system to a customer, the Company included two Disposable treatment tips are still available for sale. Tips are single-patient multiple-use products that come in different sizes, each of which are to be used for specific procedures. Tips are attached to the handpiece for use in patient procedures and, upon detachment from the handpiece, a tip cannot be reused, and it must be disposed of. Tips represent a distinct performance obligation which is satisfied either upon shipment, or upon delivery of the tips to the customer, depending on the specific contract. CUs, which are also still available for existing customers, are credits that authorize the customer to perform a procedure, or cycle. Each procedure requires a specific number of CUs, dependent upon type of tip used and procedure level selected. As the procedure is performed, the applicable number of CUs are decremented. During part of the Controlled Launch, customers purchased CUs; when the customer’s balance of CUs on a specific system was depleted, the system would no not 2023, Shipping and handling activities are not Transaction Price In the Controlled Launch, the transaction price was the consideration to which the Company expected to be entitled to in exchange for providing the promised goods to customers. Customer orders placed for cash contemplated a fixed amount of consideration. Customer orders placed by physicians participating in the Controlled Launch when they elected to purchase the CellFX System were paid for via conversion of accumulated earned credits for prior services provided by the physicians under the terms of their participation in the Controlled Launch. For these transactions, the transaction price included noncash consideration. The services rendered by the physicians in the Controlled Launch were accounted for separately from the subsequent sales of the CellFX Systems because they were distinct from the system sales. They were distinct because they provided the Company with treatment data that could also be procured, and historically had been procured by the Company, without the corresponding system sales. This data was used by the Company to enhance marketing and promotion of its products. The Company evaluated the possible impact of variable consideration in determining the transaction price, in particular the possibility of future returns or credits. Still outstanding sales agreements allow for a right of return only if the product does not no The Company has made an accounting policy election to exclude from the measurement of the transaction price all taxes which are imposed on and concurrent with a specific revenue-producing transaction and collected by the entity from a customer. When there are multiple performance obligations present, the total transaction price shall be allocated to each of the performance obligations based upon the relative SSPs of those performance obligations. The Company establishes SSPs based on multiple factors including, prices charged by the Company for similar offerings, product-specific business objectives, and the estimated cost to provide the performance obligation. However, upon the sale of a new CellFX System, all performance obligations are delivered concurrently and therefore there is no not no Controlled Launch Agreements In August 2021, 9

Note 11 - Segment Reporting

Note 11 - Segment Reporting	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Segment Reporting Disclosure [Text Block]	11. The Company operates and manages the business as one reportable and operating segment. The Company’s Chief Executive Officer acts as the chief operating decision maker (“CODM”) of the Company. The CODM reviews the results of the Company on a consolidated basis, however in making certain operating decisions and assessing performance, the CODM has additionally reviewed the disaggregated revenue results by product and geography. All of the Company’s long-lived assets are based in the United States. Revenue by product consisted of the following (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Systems $ — $ — $ — $ 576 Cycle units — — — 133 Total consolidated revenue $ — $ — $ — $ 709 Revenue by geography consisted of the following (in thousands): Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 North America $ — $ — $ — $ 526 Rest of World — — — 183 Total consolidated revenue $ — $ — $ — $ 709

Note 12 - Related Party Transac

Note 12 - Related Party Transactions	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Related Party Transactions Disclosure [Text Block]	12. Related Party Transactions In May 2022, not May 31, 2022, one third May 31, 2023, one September 30, 2023 On September 20, 2022, 2022 April 30, 2023, 2022 April 30, 2023. 2022 No 2022 8

Note 13 - Restructuring Charges

Note 13 - Restructuring Charges	9 Months Ended
	Sep. 30, 2023
Notes to Financial Statements
Restructuring and Related Activities Disclosure [Text Block]	13. Restructuring Charges On March 31, 2022, March 31, 2022. March 2022 nine September 30, 2022. In February 2023, seven February 2023 nine September 30, 2023.

Significant Accounting Policies

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared on a basis consistent with the Company’s December 31, 2022 December 31, 2022 not 10 December 31, 2022 three nine September 30, 2023 not
Consolidation, Policy [Policy Text Block]	Principles of Consolidation The accompanying condensed consolidated financial statements include the financial statements of Pulse Biosciences, Inc. and its wholly-owned subsidiaries. Intercompany balances and transactions, if any, have been eliminated in consolidation.
Use of Estimates, Policy [Policy Text Block]	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires the Company to make estimates and assumptions that affect the amounts reported in the Financial Statements and accompanying notes to the condensed consolidated financial statements. Estimates include, but are not
Share-Based Payment Arrangement [Policy Text Block]	Stock-Based Compensation The Company's stock-based compensation programs include stock options and an employee stock purchase program. The Company accounts for stock-based compensation using the fair value method. The Company periodically issues stock options to officers, directors, employees, and consultants for services rendered. Such issuances vest and expire according to terms established at the issuance date. Stock-based payments to officers, directors and employees, including grants of employee stock options, are recognized in the financial statements based on their grant date fair values, which are estimated using the Black-Scholes option-pricing model. Stock-based compensation expense is charged to operations on a straight-line basis over the vesting period. The Company has granted stock options with both time-based as well as performance-based vesting conditions. For stock awards with performance-based vesting conditions, the Company does not may The Company has also issued certain stock options with market-based vesting conditions. These vesting conditions relate to the achievement of certain market capitalization targets of the Company. The grant date fair value for these stock options was determined using a Monte Carlo simulation. The expense is recognized over the requisite service period for each tranche of the awards. The requisite service period is the service period derived from the Monte Carlo simulation model. If the market capitalization targets are met sooner than the derived service period, the Company will accelerate the recognition of stock-based compensation expense to reflect the cumulative expense associated with the vested shares. The Monte Carlo simulation requires the Company to make assumptions and judgements about the variables used in the calculation including the expected term, volatility of the Company's common stock, an assumed risk-free interest rate, and cost of equity. The assumptions used in the option-pricing model represent management’s best estimates. If factors change and different assumptions are used, the Company's stock-based compensation expense could be materially different in the future. See Note 6
Inventory, Policy [Policy Text Block]	Valuation of Inventory Inventory is stated at lower of cost or net realizable value. The Company establishes the inventory basis by determining the cost based on standard costs approximating the purchase costs on a first first December 31, 2022, not
Revenue from Contract with Customer [Policy Text Block]	Revenue from Contracts with Customers The Company recognized revenue at a point in time when it satisfied performance obligations by transferring control of promised goods to its customers. The amount of revenue recognized was equal to the consideration which the Company was entitled to in exchange for the promised goods, excluding any amounts assessed by government authorities for taxes which might have been collected from a customer. Sales contracts often involved the sale and delivery of multiple products, each of which typically represented a separate performance obligation in the contract. While the Company has sold these products on a stand-alone basis at their respective stand-alone selling prices (“SSP”), initial customer contracts primarily involved the bundling of products which were delivered concurrently to the customer. In such instances, the full consideration of the contract was recognized upon shipment of the products. The Company generally required receipt of full payment prior to shipment, however, from time to time, payment terms were extended to customers upon which the Company performed a necessary credit evaluation to ensure future collectability of the outstanding balance. The accounts receivable balance at September 30, 2023 zero not 10
Standard Product Warranty, Policy [Policy Text Block]	Product Warranty The Company provides a standard warranty on eligible products which provides the customer assurances that the products comply with the agreed-upon specifications. The standard warranty does not may nine September 30, 2023, Warranty accrual activity consisted of the following for the three nine September 30, 2023 2022 Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Beginning balance $ — $ 122 $ 50 $ 80 Add: Accruals for warranties issued during the period — — — 42 Less: Adjustment for inventory at cost — (15 ) (50 ) (15 ) Ending balance $ — $ 107 $ — $ 107
Earnings Per Share, Policy [Policy Text Block]	Net Loss per Share The Company calculates basic net loss per share by dividing net loss by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share is computed by giving effect to all potential dilutive common stock equivalents outstanding during the period. For purposes of this calculation, options to purchase common stock and common stock warrants are considered common stock equivalents. Potential common shares that have an anti-dilutive effect (i.e., those that increase income per share or decrease loss per share) are excluded from the calculation of diluted net loss per share. Basic and diluted net loss per common share is the same for all periods presented because all warrants, stock options and restricted stock units outstanding are anti-dilutive. The following outstanding stock options, and warrants were excluded from the computation of diluted net loss per share for the periods presented because including them would have had an anti-dilutive effect: Nine Months Ended September 30, 2023 2022 Common stock warrants — 7,310,477 Common stock options 7,902,948 5,707,488 Total 7,902,948 13,017,965
New Accounting Pronouncements, Policy [Policy Text Block]	Recent Accounting Pronouncements There are no

Note 2 - Summary of Significa_2

Note 2 - Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2023
Notes Tables
Schedule of Product Warranty Liability [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Beginning balance $ — $ 122 $ 50 $ 80 Add: Accruals for warranties issued during the period — — — 42 Less: Adjustment for inventory at cost — (15 ) (50 ) (15 ) Ending balance $ — $ 107 $ — $ 107
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	Nine Months Ended September 30, 2023 2022 Common stock warrants — 7,310,477 Common stock options 7,902,948 5,707,488 Total 7,902,948 13,017,965

Note 3 - Fair Value of Financ_2

Note 3 - Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2023
Notes Tables
Fair Value, Assets Measured on Recurring Basis [Table Text Block]	September 30, 2023 Assets Classification Level 1 Level 2 Level 3 Total Money market funds Cash and cash equivalents $ 48,563 $ — $ — $ 48,563 Total assets measured at fair value $ 48,563 $ — $ — $ 48,563 December 31, 2022 Assets Classification Level 1 Level 2 Level 3 Total Money market funds Cash and cash equivalents $ 57,973 $ — $ — $ 57,973 Total assets measured at fair value $ 57,973 $ — $ — $ 57,973

Note 4 - Balance Sheet Compon_2

Note 4 - Balance Sheet Components (Tables)	9 Months Ended
	Sep. 30, 2023
Notes Tables
Property, Plant and Equipment [Table Text Block]	September 30, December 31, 2023 2022 Leasehold improvements $ 2,519 $ 2,519 Laboratory equipment 1,198 1,118 Furniture, fixtures and equipment 966 966 Software 296 289 Construction in progress 26 22 5,005 4,914 Less: Accumulated depreciation and amortization (3,357 ) (2,953 ) $ 1,648 $ 1,961
Schedule of Finite-Lived Intangible Assets [Table Text Block]	September 30, December 31, 2023 2022 Acquired patents and licenses $ 7,985 $ 7,985 Less: Accumulated amortization (5,933 ) (5,434 ) $ 2,052 $ 2,551
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]	Years ending December 31: 2023 (remaining 3 months) $ 167 2024 665 2025 665 2026 555 $ 2,052
Schedule of Accrued Liabilities [Table Text Block]	September 30, December 31, 2023 2022 Compensation expense $ 2,255 $ 1,377 Director and officer liability insurance (Note 12) — 571 Clinical trial fees and costs 8 64 Professional fees 569 318 Warranty — 50 Other 172 215 $ 3,004 $ 2,595

Note 6 - Stockholders' Equity_2

Note 6 - Stockholders' Equity and Stock-based Compensation (Tables)	9 Months Ended
	Sep. 30, 2023
Notes Tables
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Cost of revenues $ — $ 24 $ — $ 204 Research and development 982 287 1,758 1,240 Sales and marketing — (44 ) — 772 General and administrative 816 456 2,079 2,227 Total stock-based compensation expense $ 1,798 $ 723 $ 3,837 $ 4,443
Share-Based Payment Arrangement, Cost by Plan [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Time-based options $ 1,200 $ 562 $ 2,754 $ 3,814 Performance-based and market-based options 551 18 914 233 ESPP 47 143 169 396 Total stock-based compensation expense $ 1,798 $ 723 $ 3,837 $ 4,443
Share-Based Payment Arrangement, Option [Member]
Notes Tables
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Expected term in years 5.0 6.3 5.0 - 6.3 5.3 - 6.8 Expected volatility 93% 88% 89% - 94% 83% 88% Risk-free interest rate 3.7% 3.2% 3.7% 1.9% Dividend yield — — — — Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Expected term in years 4.0 - 6.3 — 4.0 - 6.3 — Expected volatility 90% — 90% — Risk-free interest rate 3.7% 3.8% — 3.4% 3.8% — Dividend yield — — — —
Market-based Options [Member]
Notes Tables
Share-Based Payment Arrangement, Option, Activity [Table Text Block]	Stock Options Outstanding Number of shares Weighted average exercise price Weighted average remaining life (in years) Balances — December 31, 2022 — $ — — Options granted 2,100,000 6.78 Options exercised — — Options canceled — — Options expired — — Balances — September 30, 2023 2,100,000 $ 6.78 9.69 Exercisable — September 30, 2023 — — —
Performance Options [Member]
Notes Tables
Share-Based Payment Arrangement, Option, Activity [Table Text Block]	Stock Options Outstanding Number of shares Weighted average exercise price Weighted average remaining life (in years) Balances — December 31, 2022 520,302 $ 10.08 7.02 Options granted 848,000 3.13 Options exercised — — Options canceled (43,500 ) 2.17 Options expired (90,672 ) 11.35 Balances — September 30, 2023 1,234,130 $ 5.49 8.81 Exercisable — September 30, 2023 195,689 $ 11.28 6.62
Time-based Options [Member]
Notes Tables
Share-Based Payment Arrangement, Option, Activity [Table Text Block]	Stock Options Outstanding Number of shares Weighted average exercise price Weighted average remaining life (in years) Balances — December 31, 2022 4,730,394 $ 12.95 6.16 Options granted 527,886 6.05 Options exercised (148,367 ) 2.48 Options canceled (131,494 ) 8.00 Options expired (409,601 ) 12.99 Balances — September 30, 2023 4,568,818 $ 12.64 6.30 Exercisable — September 30, 2023 3,458,736 $ 14.27 5.53
The 2017 Employee Stock Purchase Plan [Member]
Notes Tables
Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Expected term in years 0.5 - 1.0 0.5 - 1.0 0.5 - 1.0 0.5 - 1.0 Expected volatility 83% 83% 83% 83% Risk-free interest rate 5.4% - 5.5% 3.3% - 3.5% 5.1% - 5.5% 0.6% - 3.5% Dividend yield — — — —
The 2015 Plan, 2017 Plan and Inducement Plan [Member]
Notes Tables
Share-Based Payment Arrangement, Option, Activity [Table Text Block]	Stock Options Outstanding Number of shares Weighted average exercise price Weighted average remaining life (in years) Balances — December 31, 2022 5,250,696 $ 12.67 6.24 Options granted 3,475,886 5.78 Options exercised (148,367 ) 2.48 Options canceled (174,994 ) 6.55 Options expired (500,273 ) 12.69 Balances — September 30, 2023 7,902,948 $ 9.96 7.59 Exercisable — September 30, 2023 3,654,425 $ 14.11 5.59

Note 8 - Commitments and Cont_2

Note 8 - Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2023
Notes Tables
Schedule of Information Related to Right-of-use Assets and Lease Liabilities [Table Text Block]	September 30, December 31, Assets: 2023 2022 Right-of-use assets $ 7,466 $ 8,062 September 30, December 31, Liabilities: 2023 2022 Current operating lease liabilities $ 1,016 $ 896 Non-current operating lease liabilities 8,368 9,144 Total lease liabilities $ 9,384 $ 10,040 Nine Months Ended September 30, 2023 2022 Cash paid for operating lease liabilities $ 1,376 $ 1,353 Year ending December 31: 2023 (remaining 3 months) $ 469 2024 1,910 2025 1,977 2026 2,046 2027 2,117 Thereafter 4,075 Total lease payments 12,594 Less imputed interest (3,210 ) Total lease liabilities $ 9,384 Weighted-average remaining lease term 6.09 Weighted-average discount rate 10 %

Note 11 - Segment Reporting (Ta

Note 11 - Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2023
Notes Tables
Disaggregation of Revenue [Table Text Block]	Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Systems $ — $ — $ — $ 576 Cycle units — — — 133 Total consolidated revenue $ — $ — $ — $ 709 Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 North America $ — $ — $ — $ 526 Rest of World — — — 183 Total consolidated revenue $ — $ — $ — $ 709

Note 2 - Summary of Significa_3

Note 2 - Summary of Significant Accounting Policies - Warrant Accrual Activity (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Beginning balance	$ 0	$ 122	$ 50	$ 80
Add: Accruals for warranties issued during the period	0	0	0	42
Less: Adjustment for inventory at cost	0	(15)	(50)	(15)
Ending balance	$ 0	$ 107	$ 0	$ 107

Note 2 - Summary of Significa_4

Note 2 - Summary of Significant Accounting Policies - Antidilutive Securities (Details) - shares	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Antidilutive securities (in shares)	7,902,948	13,017,965
Warrant [Member]
Antidilutive securities (in shares)	0	7,310,477
Share-Based Payment Arrangement, Option [Member]
Antidilutive securities (in shares)	7,902,948	5,707,488

Note 3 - Fair Value of Financ_3

Note 3 - Fair Value of Financial Instruments (Details Textual) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value, Recurring [Member]
Liabilities, Fair Value Disclosure	$ 0	$ 0

Note 3 - Investments and Fair V

Note 3 - Investments and Fair Value of Financial Instruments - Financial Assets Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Total assets measured at fair value	$ 48,563	$ 57,973
Total assets measured at fair value	(48,563)	(57,973)
Fair Value, Inputs, Level 1 [Member]
Total assets measured at fair value	48,563	57,973
Total assets measured at fair value	(48,563)	(57,973)
Fair Value, Inputs, Level 2 [Member]
Total assets measured at fair value	0	0
Total assets measured at fair value	0	0
Fair Value, Inputs, Level 3 [Member]
Total assets measured at fair value	0	0
Total assets measured at fair value	0	0
Money Market Funds [Member]
Cash and Cash equivalents	48,563	57,973
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and Cash equivalents	48,563	57,973
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and Cash equivalents	0	0
Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and Cash equivalents	$ 0	$ 0

Note 4 - Balance Sheet Compon_3

Note 4 - Balance Sheet Components (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Depreciation	$ 100	$ 200	$ 404	$ 520
Finite-Lived Intangible Asset, Useful Life (Year)	12 years		12 years

Note 4 - Balance Sheet Compon_4

Note 4 - Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Property and equipment, gross	$ 5,005	$ 4,914
Less: Accumulated depreciation and amortization	(3,357)	(2,953)
Property and equipment, net	1,648	1,961
Leasehold Improvements [Member]
Property and equipment, gross	2,519	2,519
Laboratory Equipment [Member]
Property and equipment, gross	1,198	1,118
Furniture and Fixtures [Member]
Property and equipment, gross	966	966
Software and Software Development Costs [Member]
Property and equipment, gross	296	289
Construction in Progress [Member]
Property and equipment, gross	$ 26	$ 22

Note 4 - Balance Sheet Compon_5

Note 4 - Balance Sheet Components - Intangible Assets, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Less: Accumulated amortization	$ (5,933)	$ (5,434)
Finite-Lived Intangible Assets, Net	2,052	2,551
Acquired Patents and Licenses [Member]
Acquired patents and licenses	$ 7,985	$ 7,985

Note 4 - Balance Sheet Compon_6

Note 4 - Balance Sheet Components - Schedule of Amortization of Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
2023 (remaining 3 months)	$ 167
2024	665
2025	665
2026	555
Finite-Lived Intangible Assets, Net	$ 2,052	$ 2,551

Note 4 - Balance Sheet Compon_7

Note 4 - Balance Sheet Components - Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Compensation expense	$ 2,255		$ 1,377
Director and officer liability insurance (Note 12)	0		571
Clinical trial fees and costs	8		64
Professional fees	569		318
Warranty	0	$ 0	50	$ 107	$ 122	$ 80
Other	172		215
Accrued Liabilities, Current	$ 3,004		$ 2,595

Note 5 - Goodwill (Details Text

Note 5 - Goodwill (Details Textual) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2022 USD ($)
Goodwill, Ending Balance	$ 2,791		$ 2,791
Goodwill, Impairment Loss	$ 0
Series of Individually Immaterial Business Acquisitions [Member]
Number of Businesses Acquired		3
Business Combination, Consideration Transferred, Total		$ 5,500
Goodwill, Ending Balance		$ 2,800

Note 6 - Stockholders' Equity_3

Note 6 - Stockholders' Equity and Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended		3 Months Ended	6 Months Ended	9 Months Ended		12 Months Ended
	Apr. 30, 2023	Jan. 01, 2023	Jun. 09, 2022	May 31, 2021	Nov. 30, 2017	Sep. 30, 2023	Jun. 15, 2023	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2017	Dec. 31, 2022
Common Stock, Par or Stated Value Per Share (in dollars per share)						$ 0.001		$ 0.001			$ 0.001
Proceeds from Issuance of Common Stock								$ 0	$ 14,893
Proceeds from Warrant Exercises								14,828	$ 15
Time-based Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Intrinsic Value								$ 2,400
Time-based Options [Member] | Share-Based Payment Arrangement, Tranche One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage								25%
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)								1 year
Performance Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Intrinsic Value								$ 1,900
Market-based Options [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Intrinsic Value								$ 10,400
The 2017 Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)										10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)										1,500,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)		1,200,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Number of Shares (in shares)										1,200,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Percent										4%
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)						585,108		585,108
The 2017 Inducement Equity Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)					10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)					1,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)				1,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)						1,249,126		1,249,126
The 2017 Inducement Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Tranche One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage					25%
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)					1 year
The 2017 Inducement Equity Incentive Plan [Member] | Share-Based Payment Arrangement, Option [Member] | Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)					10 years
The 2017 Employee Stock Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)										250,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Number of Shares (in shares)										450,000
Increase in Shares Available for Issuance, Threshold of Common Stock Outstanding, Percent										1.50%
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)						113,318		113,318
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)						85,211		347,681
Rights Offering Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)			1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 2.05			$ 2.05		$ 2.05
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						7,317,072		7,317,072
Class of Warrants or Rights, Redemption Price Per Share (in dollars per share)						$ 0.01		$ 0.01
Class of Warrant or Right, Period of Written Notice for Exercise (Day)								30 days
Class of Warrant or Right, Percentage Required for Redemption						200%		200%
Class of Warrant or Right, Exercise, Consecutive Trading Days (Day)								20 days
Class of Warrant or Right, Exercised During Period (in shares)							7,250,897	66,175
Proceeds from Warrant Exercises							$ 14,900
Class of Warrant or Right, Outstanding (in shares)						0		0
Loan Agreement [Member]
Debt Instrument, Decrease, Forgiveness	$ 65,000
Private Placement [Member] | Robert W. Duggan [Member]
Stock Issued During Period, Shares, New Issues (in shares)	10,022,937
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.001
Shares Issued, Price Per Share (in dollars per share)	$ 6.51
Rights Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)			7,317,072
Common Stock, Par or Stated Value Per Share (in dollars per share)			$ 0.001
Shares Issued, Price Per Share (in dollars per share)			$ 2.05
Equity Offering, Units, Sale of Units (in shares)			7,317,072
Number of Shares Per Unit Issued (in shares)			1
Number of Warrants Per Unit (in shares)			1
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)			7,317,072
Proceeds from Issuance of Common Stock			$ 15,000
Class of Warrants or Rights, Redemption Price Per Share (in dollars per share)			$ 0.01
Rights Offering [Member] | Board of Directors Chairman [Member]
Investment Owned, Percent of Net Assets			56%

Note 6 - Stockholders' Equity_4

Note 6 - Stockholders' Equity and Stock-based Compensation - Summary of Stock Option Activity (Details) - The 2015 Plan, 2017 Plan and Inducement Plan [Member]	9 Months Ended	12 Months Ended
	Sep. 30, 2023 $ / shares shares	Dec. 31, 2022 $ / shares shares
Options balances, number of shares (in shares) | shares	5,250,696
Options balances, weighted average exercise price (in dollars per share) | $ / shares	$ 12.67
Options balances, weighted average remaining life (Year)	7 years 7 months 2 days	6 years 2 months 26 days
Options granted, number of shares (in shares) | shares	3,475,886
Options granted, weighted average exercise price (in dollars per share) | $ / shares	$ 5.78
Options exercised, number of shares (in shares) | shares	(148,367)
Options exercised, weighted average exercise price (in dollars per share) | $ / shares	$ 2.48
Options canceled, number of shares (in shares) | shares	(174,994)
Options canceled, weighted average exercise price (in dollars per share) | $ / shares	$ 6.55
Options expired, number of shares (in shares) | shares	(500,273)
Options expired, weighted average exercise price (in dollars per share) | $ / shares	$ 12.69
Options balances, number of shares (in shares) | shares	7,902,948	5,250,696
Options balances, weighted average exercise price (in dollars per share) | $ / shares	$ 9.96	$ 12.67
Options exercisable, number of shares (in shares) | shares	3,654,425
Options exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 14.11
Options exercisable, weighted average remaining life (Year)	5 years 7 months 2 days

Note 6 - Stockholders' Equity_5

Note 6 - Stockholders' Equity and Stock-based Compensation - Summary of Time-based Option Activity (Details) - Time-based Options [Member]	9 Months Ended	12 Months Ended
	Sep. 30, 2023 $ / shares shares	Dec. 31, 2022 $ / shares shares
Options balances, number of shares (in shares) | shares	4,730,394
Options balances, weighted average exercise price (in dollars per share) | $ / shares	$ 12.95
Options balances, weighted average remaining life (Year)	6 years 3 months 18 days	6 years 1 month 28 days
Options granted, number of shares (in shares) | shares	527,886
Options granted, weighted average exercise price (in dollars per share) | $ / shares	$ 6.05
Options exercised, number of shares (in shares) | shares	(148,367)
Options exercised, weighted average exercise price (in dollars per share) | $ / shares	$ 2.48
Options canceled, number of shares (in shares) | shares	(131,494)
Options canceled, weighted average exercise price (in dollars per share) | $ / shares	$ 8
Options expired, number of shares (in shares) | shares	(409,601)
Options expired, weighted average exercise price (in dollars per share) | $ / shares	$ 12.99
Options balances, number of shares (in shares) | shares	4,568,818	4,730,394
Options balances, weighted average exercise price (in dollars per share) | $ / shares	$ 12.64	$ 12.95
Options exercisable, number of shares (in shares) | shares	3,458,736
Options exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 14.27
Options exercisable, weighted average remaining life (Year)	5 years 6 months 10 days

Note 6 - Stockholders' Equity_6

Note 6 - Stockholders' Equity and Stock-based Compensation - Summary of Performance Option Activity (Details) - Performance Options [Member]	9 Months Ended	12 Months Ended
	Sep. 30, 2023 $ / shares shares	Dec. 31, 2022 $ / shares shares
Options balances, number of shares (in shares) | shares	520,302
Options balances, weighted average exercise price (in dollars per share) | $ / shares	$ 10.08
Options balances, weighted average remaining life (Year)	8 years 9 months 21 days	7 years 7 days
Options granted, number of shares (in shares) | shares	848,000
Options granted, weighted average exercise price (in dollars per share) | $ / shares	$ 3.13
Options exercised, number of shares (in shares) | shares	0
Options exercised, weighted average exercise price (in dollars per share) | $ / shares	$ 0
Options canceled, number of shares (in shares) | shares	(43,500)
Options canceled, weighted average exercise price (in dollars per share) | $ / shares	$ 2.17
Options expired, number of shares (in shares) | shares	(90,672)
Options expired, weighted average exercise price (in dollars per share) | $ / shares	$ 11.35
Options balances, number of shares (in shares) | shares	1,234,130	520,302
Options balances, weighted average exercise price (in dollars per share) | $ / shares	$ 5.49	$ 10.08
Options exercisable, number of shares (in shares) | shares	195,689
Options exercisable, weighted average exercise price (in dollars per share) | $ / shares	$ 11.28
Options exercisable, weighted average remaining life (Year)	6 years 7 months 13 days

Note 6 - Stockholders' Equity_7

Note 6 - Stockholders' Equity and Stock-based Compensation - Summary of Market-based Option Activity (Details) - Market-based Options [Member] - $ / shares	9 Months Ended
	Sep. 30, 2023
Options balances, number of shares (in shares)	0
Options balances, weighted average exercise price (in dollars per share)	$ 0
Options granted, number of shares (in shares)	2,100,000
Options granted, weighted average exercise price (in dollars per share)	$ 6.78
Options exercised, number of shares (in shares)	0
Options exercised, weighted average exercise price (in dollars per share)	$ 0
Options canceled, number of shares (in shares)	0
Options canceled, weighted average exercise price (in dollars per share)	$ 0
Options expired, number of shares (in shares)	0
Options expired, weighted average exercise price (in dollars per share)	$ 0
Options balances, number of shares (in shares)	2,100,000
Options balances, weighted average exercise price (in dollars per share)	$ 6.78
Options balances, weighted average remaining life (Year)	9 years 8 months 8 days
Options exercisable, number of shares (in shares)	0
Options exercisable, weighted average exercise price (in dollars per share)	$ 0

Note 6 - Stockholders' Equity_8

Note 6 - Stockholders' Equity and Stock-based Compensation - Option Assumptions (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Time-based and Performance Options [Member]
Expected volatility			94%
Risk-free interest rate		3.20%	3.80%	3.20%
Dividend yield		0%
Market-based Options [Member]
Expected volatility	90%	0%	90%	0%
Risk-free interest rate		0%		0%
Dividend yield	0%	0%	0%	0%
Minimum [Member] | Time-based and Performance Options [Member]
Expected term in years (Year)	5 years
Expected volatility	93%
Minimum [Member] | Market-based Options [Member]
Expected term in years (Year)	4 years		4 years
Maximum [Member] | Time-based and Performance Options [Member]
Expected term in years (Year)			5 years	5 years 3 months 18 days
Expected volatility			89%
Maximum [Member] | Market-based Options [Member]
Expected term in years (Year)	6 years 3 months 18 days		6 years 3 months 18 days

Note 6 - Stockholders' Equity_9

Note 6 - Stockholders' Equity and Stock-based Compensation - ESPP Assumptions (Details) - The 2017 Employee Stock Purchase Plan [Member]	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Expected volatility	83%	83%	83%	83%
Dividend yield	0%	0%	0%	0%
Minimum [Member]
Expected term in years (Year)	6 months	6 months	6 months	6 months
Risk-free interest rate	5.40%	3.30%	5.10%	0.60%
Maximum [Member]
Expected term in years (Year)	1 year	1 year	1 year	1 year
Risk-free interest rate	5.50%	3.50%	5.50%	3.50%

Note 6 - Stockholders' Equit_10

Note 6 - Stockholders' Equity and Stock-based Compensation - Stock-based Compensation Expense by Recorded Location (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Total stock-based compensation expense	$ 1,798	$ 1,798	$ 723	$ 3,837	$ 4,443
Cost of Sales [Member]
Total stock-based compensation expense	0		24	0	204
Research and Development Expense [Member]
Total stock-based compensation expense	982		287	1,758	1,240
Selling and Marketing Expense [Member]
Total stock-based compensation expense	0		(44)	0	772
General and Administrative Expense [Member]
Total stock-based compensation expense	$ 816		$ 456	$ 2,079	$ 2,227

Note 6 - Stockholders' Equit_11

Note 6 - Stockholders' Equity and Stock-based Compensation - Stock-based Compensation Expense by Type (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Total stock-based compensation expense	$ 1,798	$ 1,798	$ 723	$ 3,837	$ 4,443
Time-based Options [Member]
Total stock-based compensation expense		1,200	562	2,754	3,814
Performance-based and Market-based Options [Member]
Total stock-based compensation expense		551	18	914	233
Employee Stock Purchase Plan Award [Member]
Total stock-based compensation expense		$ 47	$ 143	$ 169	$ 396

Note 7 - Research Grants and _2

Note 7 - Research Grants and Agreements (Details Textual) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	May 31, 2021	Mar. 31, 2021	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Research and Development Expense			$ 7,472	$ 4,517	$ 19,998	$ 16,744
Old Dominion University Research Foundation [Member] | Sponsored Research Agreement SRA [Member]
Research and Development Expense			$ 0	$ 0	$ 0	$ 200
Old Dominion University Research Foundation [Member] | Sponsored Research Agreement SRA [Member] | Research and Development Arrangement [Member]
Long-Term Purchase Commitment, Amount	$ 300	$ 300

Note 8 - Commitments and Cont_3

Note 8 - Commitments and Contingencies (Details Textual) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
	Apr. 30, 2023 USD ($) $ / shares shares	Sep. 30, 2023 USD ($) $ / shares	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) $ / shares	Sep. 30, 2022 USD ($)	Dec. 31, 2022 $ / shares	Sep. 20, 2022 USD ($)	May 31, 2019 a	Jul. 31, 2017 a
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares		$ 0.001		$ 0.001		$ 0.001
Operating Lease, Expense		$ 0.6	$ 0.5	$ 1.7	$ 1.5
Corporate Headquarters in Hayward, California [Member]
Lessee, Operating Lease, Term of Contract (Year)									5 years
Area of Real Estate Property (Acre) | a									15,700
Corporate Headquarters in Hayward, California [Member] | Expansion Premises 1 [Member]
Area of Real Estate Property (Acre) | a								13,300
Corporate Headquarters in Hayward, California [Member] | Expansion Premises 2 [Member]
Area of Real Estate Property (Acre) | a								21,300
Robert W. Duggan [Member] | Private Placement [Member]
Stock Issued During Period, Shares, New Issues (in shares) | shares	10,022,937
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares	$ 0.001
Shares Issued, Price Per Share (in dollars per share) | $ / shares	$ 6.51
Two Thousand Twenty Two Loan Agreement [Member] | Robert W. Duggan [Member]
Debt Instrument, Face Amount							$ 65
Debt Instrument Quarterly Interest Rate							5
Debt Instrument, Increase, Accrued Interest				1.7
Interest Expense				$ 1.1
Loan Agreement [Member]
Debt Instrument, Decrease, Forgiveness	$ 65
Interest Payable	$ 0.2

Note 8 - Commitments and Cont_4

Note 8 - Commitments and Contingencies - Information Related to Right-of-use Assets and Lease Liabilities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Right-of-use assets	$ 7,466		$ 8,062
Current operating lease liabilities	1,016		896
Non-current operating lease liabilities	8,368		9,144
Total lease liabilities	9,384		$ 10,040
Cash paid for operating lease liabilities	1,376	$ 1,353
2023 (remaining 3 months)	469
2024	1,910
2025	1,977
2026	2,046
2027	2,117
Thereafter	4,075
Total lease payments	12,594
Less imputed interest	$ (3,210)
Weighted-average remaining lease term (Year)	6 years 1 month 2 days
Weighted-average discount rate	10%

Note 9 - Controlled Launch (Det

Note 9 - Controlled Launch (Details Textual) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Feb. 28, 2021
Number of KOLs					70
Controlled Launch, Program Expenses	$ 0	$ 0	$ 0	$ 600
Revenue from Contract with Customer, Excluding Assessed Tax	$ 0	0	0	709
Redemption of Non Cash Credits [Member]
Revenue from Contract with Customer, Excluding Assessed Tax		$ 0	$ 0	$ 400
Minimum [Member]
Number of Patients Participating in Procedure					40
Maximum [Member]
Number of Patients Participating in Procedure					50

Note 10 - Revenue (Details Text

Note 10 - Revenue (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenue from Contract with Customer, Excluding Assessed Tax	$ 0	$ 0	$ 0	$ 709
Redemption of Non Cash Credits [Member]
Revenue from Contract with Customer, Excluding Assessed Tax		$ 0	$ 0	$ 400

Note 11 - Segment Reporting (De

Note 11 - Segment Reporting (Details Textual)	9 Months Ended
	Sep. 30, 2023
Number of Reportable Segments	1

Note 11 - Segment Reporting - R

Note 11 - Segment Reporting - Revenue by Product (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Total revenues	$ 0	$ 0	$ 0	$ 709
North America [Member]
Total revenues	0	0	0	526
Rest of World [Member]
Total revenues	0	0	0	183
System Products [Member]
Total revenues	0	0	0	576
Cycle Units Products [Member]
Total revenues	$ 0	$ 0	$ 0	$ 133

Note 12 - Related Party Trans_2

Note 12 - Related Party Transactions (Details Textual) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended
	May 31, 2023	Apr. 30, 2023	Sep. 20, 2022	Mar. 31, 2023	Sep. 30, 2023	Dec. 31, 2022
Accrued Liabilities, Current					$ 3,004	$ 2,595
Common Stock, Par or Stated Value Per Share (in dollars per share)					$ 0.001	$ 0.001
Loan Agreement [Member]
Debt Instrument, Decrease, Forgiveness		$ 65,000
Interest Payable		$ 200
Robert W. Duggan [Member] | Private Placement [Member]
Stock Issued During Period, Shares, New Issues (in shares)		10,022,937
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.001
Shares Issued, Price Per Share (in dollars per share)		$ 6.51
Letter Agreement [Member] | Robert W. Duggan [Member]
Directors and Officers Liability Insurance, Period (Year)				1 year
Related Party Transaction, Amounts of Transaction	$ 1,000		$ 65,000
Accrued Liabilities, Current					$ 0

Note 13 - Restructuring Charg_2

Note 13 - Restructuring Charges (Details Textual) - Employee Severance [Member] $ in Millions	1 Months Ended
	Feb. 28, 2023 USD ($)	Mar. 31, 2022 USD ($)
Restructuring and Related Cost, Number of Positions Eliminated	7
Total Cost and Expenses [Member]
Restructuring Charges	$ 0.1
Total Cost and Expenses [Member] | March 2022 Restructuring Plan [Member]
Restructuring Charges		$ 0.7