Condensed Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Cash flows from operating activities
Net loss	$ (15,240)	$ (16,439)
Adjustments to reconcile net loss to net cash used in operating activities
Stock-based compensation expense	5,854	5,088
Depreciation	104	103
Amortization of debt discount and issuance costs	104	132
Non-cash interest expense	390	540
Loss on debt extinguishment	527	0
PIK interest incurred but not paid on term loan	0	1,389
Amortization of right-of-use asset	835	764
Loss (gain) on short-term investments	41	(96)
Inventory write-downs	93	89
Loss on disposal of property and equipment	2	0
Changes in operating assets and liabilities
Accounts receivable	(704)	1,071
Inventory	(3,058)	(238)
Prepaid expenses and other assets	671	653
Accounts payable	1,703	28
Accrued liabilities	(120)	(3,436)
Deferred revenue	141	(280)
Operating lease liabilities	(911)	(796)
Net cash used in operating activities	(9,568)	(11,428)
Cash flows from investing activities
Acquisition of property and equipment	(205)	(167)
Proceeds from sale of short-term investments	0	5,800
Net cash (used in) provided by investing activities	(205)	5,633
Cash flows from financing activities
Repurchase of common stock	(49,546)	0
Proceeds from issuance of common stock under employee plans	1,151	1,302
Taxes withheld and paid related to net share settlement of equity awards	(402)	(721)
Net cash provided by financing activities	19,200	581
Net increase (decrease) in cash and cash equivalents	9,427	(5,214)
Cash, cash equivalents and restricted cash
Beginning of the period	13,552	18,180
End of the period	22,979	12,966
Reconciliation of cash, cash equivalents and restricted cash to balance sheets:
Cash and cash equivalents	22,857	12,844
Restricted cash	122	122
Cash, cash equivalents and restricted cash in balance sheets	22,979	12,966
Supplemental disclosure of cash flow information:
Cash paid for interest	3,276	2,362
Supplemental disclosures of non-cash investing and financing information:
Follow-on offering costs included in accounts payable and accrued liabilities	50	0
Debt issuance costs included in accounts payable and accrued liabilities	82	0
Deferred offering costs offset against additional paid-in capital	277	0
Purchase of property and equipment included in accounts payable	25	0
Net change in accrued liabilities from early exercise of options	0	(1)
Follow-on Offering
Cash flows from financing activities
Proceeds from issuance of stock	69,704	0
At-the-Market Equity Offering
Cash flows from financing activities
Proceeds from issuance of stock	232	0
Proceeds from debt, net of discounts and issuance costs	58,568	0
Repayment of debt	$ (60,507)	$ 0