Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Revenues	$ 8,273	$ 10,130
Cost of revenues	5,619	6,706
Gross profit	2,654	3,424
Operating expenses:
Research and development	4,390	5,900
Selling, general and administrative	14,221	15,625
Total operating expenses	18,611	21,525
Loss from operations	(15,957)	(18,101)
Interest expense, net	(1,665)	(1,648)
Other (expense) income, net	(1)	2,337
Net loss and comprehensive loss	(17,623)	(17,412)
Accretion of preferred stock dividends	(4,510)	(4,175)
Deemed dividend arising from beneficial conversion feature of convertible preferred stock	(5,111)	0
Net loss applicable to common stockholders	$ (27,244)	$ (21,587)
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (4.36)	$ (4.57)
Weighted average common shares used to compute net loss per share, basic and diluted (in shares)	6,249	4,722