Note 7 - Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accrued expenses	$ 75	$ 157
Accrued salaries and employee benefits	661	899
Accrued clinical trial costs	1,017	548
Grant liability	471	534
Customer deposits	90	90
Total	2,385	2,246
Related Party [Member]
Payable to related party	$ 71	$ 18