Note 4 - Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Accrued interest payable		$ 37,415
Accrued Series A dividends		1,062,314
Accrued payroll and payroll related expenses	328,581	312,221
Accrued professional fees	55,993	122,711
Accrued clinical studies expenses	60,120	63,350
Other accrued expenses	67,552	30,840
Total	$ 512,246	$ 1,628,851