Note 1 - Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 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 Year Ended December 31,
	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%	-	4.26%		0.93%	-	1.66%
Expected life (years)			10				10
	Warrants
Expected dividend yield			0.0%				0.0%
Expected stock price volatility			92.2%				84.8%
Risk-free interest rate		2.96%	-	2.97%		0.42%	-	0.69%
Expected life (years)	5/			5.5	5/			5.5