Note 7 - Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2020

Notes Tables

Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]

	Three Months Ended March 31,
	2020		2019
Sales and marketing	$	13,000	$	12,000
Research and development		15,000		15,000
General and administrative		39,000		54,000
	$	67,000	$	81,000

Share-based Payment Arrangement, Option, Activity [Table Text Block]

	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life		Aggregate Intrinsic Value
Outstanding at December 31, 2019		291,807		$	13.96
Forfeited		(3,958	)	$	3.74
Outstanding at March 31, 2020		287,849		$	14.10		8.06	$	101,074
Vested and expected to vest at March 31, 2020		226,960		$	15.70		7.9	$	75,434
Exercisable at March 31, 2020		143,479		$	20.20		7.61	$	40,430

Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]

	Number of Shares			Weighted-Average Exercise Price Per Share
Balance at December 31, 2019		1,716,066		$	25.23
Warrants expired		--			--
Warrants exercised		(107,866	)	$	.53
Outstanding at March 31, 2020		1,608,200		$	26.89
Exercisable at March 31, 2020		1,538,347		$	24.47