Note 8 - Summary of Stock Options (Tables)

3 Months Ended

Mar. 31, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

	Three Months Ended March 31, 2015
						Weighted
				Weighted		Average		Aggregate
	Number			Average		Remaining		Intrinsic
	of			Exercise		Contractual		Value
	Shares			Price		Term (years)		(in thousands)
Options outstanding, beginning of period		2,291,783		$	1.02		9.32
Options granted		635,000		$	0.47
Options exercised		-		$	-
Options canceled		(21,000	)	$	1.00
Options outstanding, end of period		2,905,783		$	0.90		9.20	$	-
Vested and exercisable and expected to vest, end of period		2,664,185		$	0.93		9.16	$	-
Vested and exercisable, end of period		608,492		$	2.16		7.69	$	-

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block]

				Options Outstanding						Options Exercisable
								Weighted
				Number		Weighted		Average		Number		Weighted
				Outstanding		Average		Remaining		Exercisable		Average
Range of				as of		Exercise		Contractual		as of		Exercise
Exercise Prices				March 31, 2015		Price		Term (Years)		March 31, 2015		Price
$	0.46	-	$0.47		635,000	$	0.47		9.86		-	$	-
$			0.60		1,881,476	$	0.60		9.50		219,185	$	0.60
$			1.24		312,373	$	1.24		7.65		312,373	$	1.24
$	7.00	-	$9.00		57,603	$	8.64		2.58		57,603	$	8.64
$	12.00	-	$18.63		19,081	$	15.29		3.07		19,081	$	15.29
$			37.00		250	$	37.00		2.48		250	$	37.00
					2,905,783	$	0.90		9.20		608,492	$	2.16

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Three Months Ended
	March 31,
	2015			2014
Expected term (in years)		5			5
Average volatility		62%			67%
Risk-free interest rate	1.29%	-	1.49%	0.80%	-	0.88%
Dividend yield		0%			0%

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Three Months Ended
	March 31,
	2015		2014
Research and development	$	4	$	-
Selling, general and administrative		38		13
Total	$	42	$	13