Note 13 - Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2020

Notes Tables

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	Years ended December 31,
	2020			2019
Numerator:
Net loss	$	(15,004	)	$	(14,709	)
Denominator:
Weighted average shares used to compute net loss per share, basic and diluted		10,118,682			5,644,328
Net loss per share, basic and diluted	$	(1.48	)	$	(2.61	)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	At December 31,
	2020		2019
Stock options to purchase common stock		1,114,306		821,464
Unvested restricted stock units		8,200		36,981
Common stock warrants		2,424,724		2,435,808
Total		3,547,230		3,294,253