Statements of Operations (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue:
Total revenue	$ 8,703,583	$ 8,201,748	$ 19,805,279	$ 22,009,733
Sublease	246,530	246,532	739,590	739,593
Cost of revenue:
Total cost of revenue	4,025,255	1,831,593	6,061,651	4,391,138
Sublease	246,530	246,531	739,590	739,592
Gross margin	4,678,328	6,370,155	13,743,628	17,618,595
Operating expenses:
Research and development	1,952,641	1,751,081	6,038,753	7,405,462
Sales and marketing	2,822,680	3,120,632	8,279,853	9,666,975
General and administrative	1,466,046	1,539,648	4,962,227	4,186,277
Total operating expenses	6,241,367	6,411,361	19,280,833	21,258,714
Operating loss	(1,563,039)	(41,206)	(5,537,205)	(3,640,119)
Interest income (expense)	(9,933)	84,954	71,596	133,329
Net income (loss)	(1,572,972)	43,748	(5,465,609)	(3,506,790)
Cumulative dividend on convertible preferred stock	(343,101)	(360,647)	(1,028,950)	(1,071,351)
Loss attributable to common stockholders	$ (1,916,073)	$ (316,899)	$ (6,494,559)	$ (4,578,141)
Net loss per share attributable to common stockholders:
Basic	$ (0.03)	$ 0.00	$ (0.09)	$ (0.07)
Diluted	$ (0.03)	$ 0.00	$ (0.09)	$ (0.07)
Weighted average number of common shares and equivalents:
Basic	74,488,771	64,294,153	72,004,956	61,405,083
Diluted	74,488,771	64,294,153	72,004,956	61,405,083
Systems [Member]
Revenue:
Total revenue	$ 2,953,005	$ 1,696,964	$ 2,965,774	$ 1,755,015
Cost of revenue:
Total cost of revenue	3,031,440	665,463	3,253,976	722,828
Disposables, Service and Accessories [Member]
Revenue:
Total revenue	5,504,048	6,258,252	16,099,915	19,515,125
Cost of revenue:
Total cost of revenue	$ 747,285	$ 919,599	$ 2,068,085	$ 2,928,718