Note 1 - Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2022

Notes Tables

Property Plant and Equipment Useful Life [Table Text Block]

	Years
Computers, software, and office equipment	3	-	10
Leasehold improvements (1)	2	-	5
Manufacturing tooling	3	-	7
Laboratory equipment	4	-	10
Demo equipment		3

Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]

	For the nine months ended September 30,
	2022	2021
	Stock Options
Expected dividend yield	0.0%	0.0%
Expected stock price volatility	86.5% - 92.2%	84.8% - 89.6%
Risk-free interest rate	1.83% - 3.43%	0.93% - 1.45%
Expected life (years)	10	10
	Warrants
Expected dividend yield	0.0%	0.0%
Expected stock price volatility	92.2%	84.8% - 89.6%
Risk-free interest rate	2.96% - 2.97%	0.42% - 1.04%
Expected life (years)	5 - 5.5	5 - 5.5