Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($)	Mar. 31, 2020	Dec. 31, 2019	[1]
Current assets:
Cash and cash equivalents	$ 9,042,000	$ 13,308,000
Accounts receivable, net of allowance for doubtful accounts of $481 and $407 as of March 31, 2020 and December 31, 2019, respectively	1,279,000	1,573,000
Inventory	4,459,000	4,861,000
Prepaid expenses and other current assets	2,204,000	2,447,000
Total current assets	16,984,000	22,189,000
Property and equipment, net	2,973,000	3,046,000
Investment in limited liability company	1,034,000	1,216,000
Other assets	441,000	526,000
Total assets	21,432,000	26,977,000
Current liabilities:
Accounts payable	2,262,000	1,608,000
Accrued liabilities	2,323,000	4,698,000
Total current liabilities	4,585,000	6,306,000
Note payable, noncurrent portion	4,110,000	3,983,000
Other noncurrent liabilities	186,000	167,000
Total liabilities	8,881,000	10,456,000
Commitments and contingences (Note 8)
Stockholders’ equity:
Common stock, $0.0001 par value; 75,000,000 shares authorized as of March 31, 2020 and December 31, 2019; 10,028,203 and 7,075,684 shares issued and outstanding as of March 31, 2020 and December 31, 2019, respectively	1,000	1,000
Additional paid-in capital	216,771,000	214,431,000
Accumulated deficit	(204,221,000)	(197,911,000)
Total stockholders’ equity	12,551,000	16,521,000
Total liabilities and stockholders’ equity	21,432,000	26,977,000
Series A Preferred Stock [Member]
Stockholders’ equity:
Convertible preferred stock
Series B Preferred Stock [Member]
Stockholders’ equity:
Convertible preferred stock

[1] The condensed consolidated balance sheet as of December 31, 2019 has been derived from the audited consolidated financial statements as of that date.