Note 11 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Notes Tables

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	December 31
	2022			2021
Net operating loss carryforwards	$	14,264		$	13,385
Stock options and warrants		1,151			832
Property and equipment		(46	)		16
Intangible assets		875			950
Capitalized expenses		117			105
Other		655			64
Operating right-of-use lease assets		(478	)		(566	)
Operating right-of-use lease liabilities		645			670
Net deferred tax assets		17,183			15,456
Less: Valuation allowance		(17,183	)		(15,456	)
Deferred tax asset (liability)	$	-		$	-

Summary of Valuation Allowance [Table Text Block]

	2022			2021
Valuation allowances, beginning of year	$	15,456		$	12,421
Net operating loss and other temporary differences		1,997			2,926
Expiration of net operating losses and limitations		(90	)		-
Adjustment to deferred taxes		(197	)		67
Impact of state tax rate change		22			42
Other		(5	)		-
Valuation allowance, end of year	$	17,183		$	15,456

Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]

	2022			2021
Income tax benefit at federal statutory rate	$	(1,646	)	$	(1,875	)
Increase (decrease) resulting from:
State tax benefit, net of federal tax effect		(421	)		(605	)
Effect of change in state tax rate		(22	)		(42	)
Change in valuation allowance		1,727			3,035
Expirations of net operating losses and application of IRC 382 limitation		90			-
PPP loan forgiveness, nontaxable		-			(376	)
Change in fair value of derivative warrant liability, nontaxable		5			(81	)
Other nondeductible expenses		89			32
Adjustments to deferreds		197			(67	)
Income tax expense	$	19		$	21