Vistech

Vistech 

A clinical test for contrast sensitivity. It consists of a chart containing five horizontal rows, each with nine circular patches of sinusoidal gratings. The gratings are either vertical or 15º to the right or to the left. Each row has a different spatial frequency, starting from the top of the chart: 1.5, 3.0, 6.0, 12.0 and 18.0 cycles per degrees when viewed at a distance of 40 cm. The contrast level of each of the nine gratings decreases from 33% to 0% from left to right in approximately 0.2 log unit steps. The patient is asked to look along each row, identifying the orientation of the grating. The testing is carried out monocularly with optical correction, if any. The last grating of each row that is incorrectly identified is noted on an evaluation form, which is provided with the test. The end points of each of the five rows are connected to form a contrast sensitivity curve for each patient. It is then compared with normal values indicated on the form. There is also a version for testing at distance. Syn. Vision Contrast Test System (VCTS). See contrast sensitivity chart; Arden grating test.
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Local businesses helped make the garden possible, providing their services free of charge including Vistech Services, Holiday Inn Express Middlesbrough and RES Scaffolding.
However, there are two main ways of assessing contrast sensitivity in athletes: vector vision contrast sensitivity test and Vistech contrast sensitivity test.
14) Furthermore, there can be a reduction in contrast sensitivity, indicating a need to assess this using, for example, the Vistech chart or Bailie Lovie charts, and to monitor for progressive changes in AD and PD.
Visual acuity was tested at a distance of approximately 6 m (20 feet) using Landolt Cs, and contrast sensitivity was tested at a distance of about 3 m (9 feet) using the Vistech Vision Contrast Test System.
The software development concern Vistech yesterday confirmed that 12 of its 42 employees were to go.
Phase 3 of Purdue Research Park is under way with construction of Vistech 1, a 73,000-square-foot office building to house companies that graduate from the small-business incubator there.
Anadis recently announced the receiving a significant grant (see "Anadis Awarded VISTECH grant for Clinical Trial of Polyclonal Antibodies for the Treatment of Cancer Related Mucositis" July 1, 2008) to help fund this important program.
TEESSIDE security firm Vistech Services is set to create 100 jobs.
The Coalition Government seeks to work with Victorian organisations and MATIMOP, the executive agency of the Office of the Chief Scientist (OCS) of the Israeli Ministry of Economy, to assist with partner matching to support both the Feasibility and Proof of Concept grants and the VISTECH program that will be formally opened in early 2014.
Contrast sensitivity, especially at low frequencies (mediated by the magnocellular visual pathway), has been shown to be deficient in patients with AD, as measured using both the Nicolet Vision Tester and the Vistech contrast sensitivity wall chart.