Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Revenues:
Product sales	$ 7,381	$ 3,868
Other revenue	348	76
Total revenues	7,729	3,944
Cost of revenues
Products and services	4,987	2,601
Product line exit expense	747	0
Total cost of revenues	5,734	2,601
Gross profit	1,995	1,343
Operating expenses:
Selling, general and administrative	20,276	11,631
Research and development	6,214	2,789
Total operating expenses	26,490	14,420
Loss from operations	(24,495)	(13,077)
Other income (expense):
Investment income	31	83
Debt forgiveness income	0	417
Other	15	(3)
Nonoperating Income (Expense), Total	46	497
Net loss	$ (24,449)	$ (12,580)
Net loss per basic and diluted common share (in dollars per share)	$ (0.62)	$ (0.37)
Weighted average common shares used to compute net loss per basic and diluted common share (in shares)	39,281,620	33,846,338
Comprehensive loss:
Net loss	$ (24,449)	$ (12,580)
Net unrealized gain (loss) on short-term investments	(21)	15
Comprehensive loss	$ (24,470)	$ (12,565)