Note 12 - Related Party Transactions (Details Textual) - USD ($)		3 Months Ended		6 Months Ended
	Jul. 10, 2017	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021	Mar. 02, 2021	Mar. 01, 2021
Accrued Expenses, Related Party		$ 222,455		$ 222,455		$ 414,241
Interim Chief Executive Officer [Member]
Due to Related Parties, Current, Total		58,000		58,000		0
Royalty on Net Sales, Percentage							2.50%
Director Clinical Affair [Member]
Royalty on Net Sales, Percentage							2.50%	5.00%
Director of Clinical Affairs [Member]
Accounts Payable, Related Parties		81,000		81,000		123,000
Royalty Expense		81,000	$ 111,000	213,000	$ 248,000
Professional Fees		39,000	39,000	78,000	78,000
Previous President and Chief Executive Officer [Member]
Increase (Decrease) in Deferred Compensation	$ (100,000)
Employment Agreement, Base Compensation	200,000
Consultant [Member]
Deferred Compensation Arrangement with Individual, Compensation Expense		50,000		100,000
Increase (Decrease) in Deferred Compensation	(100,000)
Employment Agreement, Base Compensation	$ 200,000
Managing Director, China Operations [Member]
Deferred Compensation Arrangement with Individual, Compensation Expense		50,000	25,000	100,000	25,000
US Asian Consulting Group, LLC [Member]
Deferred Compensation Arrangement with Individual, Compensation Expense			25,000		25,000
Manufacturing Agreement for Handpieces [Member]
Related Party Transaction, Purchases from Related Party		436,000	493,000	1,700,000	878,000
Manufacturing Agreement for Handpieces [Member] | Accounts Payable, Related Parties, Current [Member]
Due to Related Parties, Current, Total		720,000		720,000		548,000
Accounts Payable, Related Parties		720,000		720,000		395,000
Accrued Expenses, Related Party		0		0		$ 153,000
Consulting Services [Member]
Related Party Transaction, Expenses from Transactions with Related Party		25,000	25,000	50,000	50,000
Deferred Compensation Arrangement with Individual, Compensation Expense		$ 0	$ 15,000	$ 0	$ 30,000