Enterprise-wide Sales Information (Details) (USD $)	3 Months Ended				6 Months Ended
	Jan. 31, 2015		Jan. 31, 2014		Jan. 31, 2015		Jan. 31, 2014
Revenue from External Customer [Line Items]
Net sales	$ 18,189,000		$ 15,096,000		$ 34,836,000		$ 30,626,000
Revenues from External Customers [Line Items]
Net sales	18,189,000		15,096,000		34,836,000		30,626,000
Alcon [Member]
Revenues from External Customers [Line Items]
Recognition of deferred revenue	322,000		322,000		644,000		644,000
Domestic [Member]
Revenues from External Customers [Line Items]
Net sales	12,887,000		11,050,000		25,041,000		22,919,000
International [Member]
Revenues from External Customers [Line Items]
Net sales	5,302,000		4,046,000		9,795,000		7,707,000
Ophthalmic [Member]
Revenue from External Customer [Line Items]
Net sales	9,985,000	[1]	9,165,000	[1]	19,510,000	[1]	18,129,000	[1]
Neurosurgery [Member]
Revenue from External Customer [Line Items]
Net sales	7,894,000	[2]	5,788,000	[2]	14,912,000	[2]	12,245,000	[2]
Other [Member]
Revenue from External Customer [Line Items]
Net sales	310,000	[3]	143,000	[3]	414,000	[3]	252,000	[3]
Ophthalmic [Member]
Revenue from External Customer [Line Items]
Net sales	8,228,000	[4]	8,739,000	[4]	16,958,000	[4]	17,237,000	[4]
OEM [Member]
Revenue from External Customer [Line Items]
Net sales	9,784,000	[5]	6,123,000	[5]	17,470,000	[5]	12,971,000	[5]
Other [Member]
Revenue from External Customer [Line Items]
Net sales	$ 177,000	[6]	$ 234,000	[6]	$ 408,000	[6]	$ 418,000	[6]

[1] Net sales from Ophthalmic represent all sales of ophthalmic devices from direct sales representatives, distribution partners and OEMs. Recognition of deferred revenue of $322,000 and $644,000 from Alcon, Inc. is included in this category for the three and six months ended January 31, 2015 and 2014, respectively.

[2] Net sales from Neurosurgery represent sales of electrosurgery generators, disposable bipolar forceps and related accessories and royalties from Codman, multi-channel generators, disposable ultrasonic tips and related accessories to Stryker and certain neurosurgery disposables sold through distribution. Many of the products that the Company sells to its neurosurgery OEM customers are shipped to their non-U.S. customers in various countries around the world, but are included in the Company's domestic revenues.

[3] Other net sales represent all sales of aesthetic devices, and other miscellaneous revenues.

[4] Net sales from Ophthalmic represent sales of ophthalmic devices from direct sales representatives and distribution partners.

[5] Net sales from OEM represent sales of electrosurgery generators, disposable bipolar forceps and related accessories and royalties from Codman, multi-channel generators, disposable ultrasonic tips and related accessories to Stryker and sales of certain disposable products. Recognition of deferred revenues of $322,000 and $644,000 from Alcon, Inc. is included in this category for the three and six months ended January 31, 2015 and 2014, respectively. Many of the products that the Company sells to its neurosurgery OEM customers are shipped to their non-U.S. customers in various countries around the world, but are included in the Company's domestic revenues.

[6] Other net sales represent direct neurosurgery revenues, and other miscellaneous revenues.