Note 12 - Segment Reporting - Summary of Operating Results by Reportable Segments (Details) - USD ($)	6 Months Ended		12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2017	Jun. 30, 2016
Net revenues	$ 6,013,000	$ 7,772,000	$ 14,525,000	$ 11,929,000
Cost of revenues	3,858,000	4,838,000	8,686,000	9,185,000
Gross profit	2,155,000	2,934,000	5,839,000	2,744,000
Operating expenses	6,753,000	8,455,000	15,079,000	13,609,000
Operating loss	(4,598,000)	(5,521,000)	(9,240,000)	(10,865,000)
Depreciation and amortization	322,000		830,000	1,168,000
Stock-based compensation expense	291,000		1,461,000	742,000
Goodwill	13,976,000		13,195,000	13,195,000
Total assets	51,111,000		46,932,000	49,899,000
Operating loss	(4,598,000)	$ (5,521,000)	(9,240,000)	(10,865,000)
Clinical Development [Member] | Operating Segments [Member]
Net revenues	186,000		492,000	646,000
Cost of revenues	205,000		466,000	574,000
Gross profit	(19,000)		26,000	72,000
Operating expenses	2,138,000		8,966,000	8,312,000
Operating loss	(2,157,000)		(8,940,000)	(8,240,000)
Depreciation and amortization	152,000		501,000	644,000
Stock-based compensation expense	164,000		970,000	548,000
Goodwill	13,195,000
Total assets	41,261,000
Operating loss	(2,157,000)		(8,940,000)	(8,240,000)
Device [Member] | Operating Segments [Member]
Net revenues	5,827,000		14,033,000	11,283,000
Cost of revenues	3,653,000		8,220,000	8,611,000
Gross profit	2,174,000		5,813,000	2,672,000
Operating expenses	4,615,000		6,113,000	5,297,000
Operating loss	(2,441,000)		(300,000)	(2,625,000)
Depreciation and amortization	170,000		329,000	524,000
Stock-based compensation expense	127,000		491,000	194,000
Goodwill	781,000
Total assets	9,850,000
Operating loss	$ (2,441,000)		$ (300,000)	$ (2,625,000)