Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 3,887	$ 11,400
Accounts receivable	519	678
Restricted cash	280	290
Inventories	469	275
Prepaid expenses and other current assets	1,136	646
Total current assets	6,291	13,289
Property and equipment, net	1,290	1,358
Other long term assets	274	162
Total assets	7,855	14,809
Current liabilities
Notes payable, net	9,475	153
Accounts payable	1,580	860
Accrued expenses	3,343	4,555
Accrued compensation	1,223	1,112
Deferred revenue	137	226
Total current liabilities	15,758	6,906
Notes payable, net	0	4,626
Warrant liability	1,841	0
Deferred revenue	0	1,000
Other long term liabilities	200	358
Total liabilities	$ 17,799	$ 12,890
Commitments and contingencies
Stockholders’ (deficit) equity
Preferred stock, $.001 par value, 10,000,000 shares authorized, no shares issued or outstanding as of December 31, 2015 and 2014, respectively	$ 0	$ 0
Common stock, $.001 par value, 150,000,000 shares authorized, 50,414,481 and 44,330,006 issued and outstanding as of December 31, 2015 and 2014, respectively	50	44
Additional paid-in-capital	298,881	291,727
Accumulated deficit	(308,875)	(289,852)
Total stockholders’ (deficit) equity	(9,944)	1,919
Total liabilities and stockholders’ (deficit) equity	$ 7,855	$ 14,809