Condensed Consolidated Statements of Operations and Comprehensive Income (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 31, 2013	Jan. 31, 2012	Jan. 31, 2013	Jan. 31, 2012
Condensed Consolidated Statements of Operations (Unaudited) [Abstract]
Net sales	$ 14,055	$ 15,080	$ 28,675	$ 28,585
Cost of sales	8,884	6,108	15,031	11,696
Gross profit	5,171	8,972	13,644	16,889
Operating expenses
Research and development	827	923	1,688	1,713
Sales and marketing	3,580	2,906	6,843	5,983
General and administrative	2,872	2,525	5,280	5,063
Total operating expenses	7,279	6,354	13,811	12,759
Operating (loss) income	(2,108)	2,618	(167)	4,130
Other income (expenses)
Investment income	6	9	13	23
Interest expense	(4)	(15)	(4)	(33)
Medical device excise tax	(45)	0	(45)	0
Miscellaneous	(20)	(4)	(23)	(6)
Total other income (expenses)	(63)	(10)	(59)	(16)
Income from continuing operations before provision for income taxes	(2,171)	2,608	(226)	4,114
Provision for income taxes	(789)	741	(196)	1,094
Income from continuing operations	(1,382)	1,867	(30)	3,020
Loss from discontinued operations	0	0	0	(382)
Net income	(1,382)	1,867	(30)	2,638
Basic
Income from continuing operations (in dollars per share)	$ (0.05)	$ 0.07	$ 0.00	$ 0.12
Loss from discontinued operations (in dollars per share)	$ 0.00	$ 0.00	$ 0.00	$ (0.02)
Net income (in dollars per share)	$ (0.05)	$ 0.07	$ 0.00	$ 0.10
Diluted
Income from continuing operations (in dollars per share)	$ (0.05)	$ 0.07	$ 0.00	$ 0.12
Loss from discontinued operations (in dollars per share)	$ 0.00	$ 0.00	$ 0.00	$ (0.02)
Net income (in dollars per share)	$ (0.05)	$ 0.07	$ 0.00	$ 0.10
Basic weighted average common shares outstanding (in share)	25,230,142	25,085,296	25,195,449	25,028,165
Diluted weighted average common shares outstanding (in share)	25,230,142	25,280,449	25,195,449	25,200,831
Net income	(1,382)	1,867	(30)	2,638
Foreign currency translation adjustment	184	122	254	93
Comprehensive income	$ (1,198)	$ 1,989	$ 224	$ 2,731