Note 3 - Revenue From Contracts With Customers and Other Revenue (Tables)

9 Months Ended

Sep. 30, 2023

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Sales revenue:
Tc99m tilmanocept - Europe	$	—	$	7,516	$	—	$	14,035

	Three Months Ended September 30,				Nine Months Ended September 30,
	2023		2022		2023		2022
Total deferred revenue related to contracts with customers, beginning of period	$	700,000	$	700,000	$	700,000	$	700,000
Deferred revenue related to milestones achieved		—		—		—		100,000
Deferred revenue related to milestones achieved, written off due to contract renegotiations		—		—		—		(100,000	)
Total deferred revenue related to contracts with customers, end of period	$	700,000	$	700,000	$	700,000	$	700,000