Note 2 - Basis of Presentation and Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2014

Accounting Policies [Abstract]

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

	Three months ended March 31,
	2014			2013
Basic and diluted loss per share:
Net loss	$	(4,070	)	$	(1,428	)
Basic and diluted loss per share:
Weighted average shares outstanding		51,725			44,699
Basic and diluted net loss per share	$	(0.08	)	$	(0.03	)

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

	Three months ended March 31,
	2014			2013
Cost of sales	$	2		$	-
Research and development		(1	)		7
Selling, general, and administrative		122			38
Total stock-based compensation	$	123		$	45

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

	Three months ended March 31,
	2014			2013
Fair value of options issued	$	0.32		$	0.15
Exercise price	$	0.42		$	0.23
Expected life of option (years)	5.6			8.3
Risk-free interest rate		1.78	%		1.57	%
Expected volatility		98.02	%		83.82	%
Dividend yield		0	%		0	%

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

	Options			Weighted Average Exercise Price		Weighted Average Remaining Contractural Term (in Years)
Outstanding as of December 31, 2013		2,861,893		$	1.53
Granted		1,950,000			0.42
Exercised		(5,000	)		0.23
Cancelled/forfeited		(273,521	)		2.00
Outstanding as of March 31, 2014		4,533,372		$	1.03		8.2
Vested and expected to vest as of March 31, 2014		4,094,707		$	0.91		8.2
Exercisable as of March 31, 2014		2,152,493		$	1.68		6.6

Schedule of Product Warranty Liability [Table Text Block]

	Three months ended March 31,
	2014			2013
Balance at the beginning of the period	$	75		$	159
Accruals for warranties issued		16			16
Settlements made during the period (in cash or in kind)		(16	)		(35	)
Balance at the end of the period	$	75		$	140