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.
Contrast sensitivity was measured using the Vistech Contrast Sensitivity Charts and no significant differences were found between index parents and parents of children with Down's Syndrome [67] (ES: 0.55).
Para evaluar la sensibilidad al contraste, estan: la grafica de Pelli-Robson (12), la prueba MARS (Mars Letter Contrast Sensitivity Test) (figura 1) (13), la prueba de sensibilidad al contraste de Vistech y la F.A.C.T.[R] (Functional Acuity Contrast Test) (8).
However, there are two main ways of assessing contrast sensitivity in athletes: vector vision contrast sensitivity test and Vistech contrast sensitivity test.
Wavefront analizi (WASCA Analyzer, Carl Zeiss Meditec AG, Jena, Germany), on segment optik kohorens tomografi (OCT) ve kontrast duyarlilik olcumu (en iyi duzeltme ile) (Vistech Consultans Inc.
This text was originally written by Anderson (VisTech) as a supplement to the regular textbook for a data mining course in the Marriott School of Management and Brigham Young U.
(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.
Por outro lado, Adams e Courage mediram a FSC de criancas de 1 mes a 9 anos, utilizando estimulos do tipo grade senoidal impressos em cartoes (Vistech Chart) e luminancia media de 70 cd/[m.sup.2], e nao encontraram diferencas significativas entre criancas de 9 anos e adultos.
Evolve senior investment executive Simon Johnson said: "VisTech has proved to be a consistent innovator and market leader in a niche sector and its new range of microscopes are set to usher in a new phase of growth."
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.