Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Product sales	$ 19,742	$ 11,022
Cost of product sales	6,217	4,276
Gross profit	13,525	6,746
Operating expenses
Research and development	1,298	1,193
Sales and marketing	2,615	2,086
General and administrative	5,950	4,523
Total operating expenses	9,863	7,802
Operating income (loss)	3,662	(1,056)
Other income (expenses)
Interest income	281	1
Interest expense	(5)	(190)
Loss from equity-method investment in SAVSU	(672)	(1,005)
Financing costs and write off of deferred financing costs		(109)
Amortization of debt discount		(156)
Total other income (expenses)	(396)	(1,459)
Net income (loss) before provision for income taxes	3,266	(2,515)
Income taxes
Net income (loss)	3,266	(2,515)
Less: Preferred stock dividends and accumulated deficit impact of preferred stock redemption	(339)	(213)
Net income (loss) attributable to common stockholders	$ 2,927	$ (2,728)
Basic net income (loss) per common share (in dollars per share)	$ 0.18	$ (0.21)
Diluted net income (loss) per common share (in dollars per share)	$ 0.14	$ (0.21)
Weighted average shares outstanding used to compute basic earnings per share (in shares)	16,256,465	13,263,881
Weighted average shares outstanding used to compute diluted earnings per share (in shares)	21,627,278	13,263,881