Property and Equipment, Net - Schedule of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 19,576	$ 12,781
Less: Accumulated depreciation and amortization	(9,735)	(8,027)
Property and equipment, net	9,841	4,754
Manufacturing Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,769	1,725
OCS Consoles Loaned To Customers [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	8,865	7,196
Computer Equipment and Software [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,511	1,338
Laboratory Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	668	617
Office and Trade Show Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	177	177
Leasehold Improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,319	1,319
Construction-In-Progress [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 5,267	$ 409

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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