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SUSSEX
VISION INTERNATIONAL
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01903 851 951
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RETURN TO 'DISTANCE LOGMAR CHARTS' PRICELIST What does ETDRS mean? Early Treatment Diabetic Retinopath Study Note to the reader: All information was obtained from research done by: Frederick L. Ferris III, M.D., Aaron Kassoff, M.D., George H. Bresnick, M.D. and Ian Bailey, M.D. This Article is published in American Journal of Ophthalmology 1982. If you wish to read it in its entirety please contact Sussex Vision Ltd on 01903 851951 Original and Revised ETDRS Charts These visual acuity charts facilitate quantitative use of visual acuity test results. The charts have high-contrast lettering on washable (using a mild detergent) white polystyrene. Each line has five Sloan letters; the lines are of equal difficulty, and there is a geometric progression (LogMar) in letter size from line to line. This provides a similar task for each line on the chart with the letter size being the only variable. Charts with different letter sequences are used for testing right and left eyes, with a third chart for refractions. The smallest line on the chart that the individual could read is used to quantify his visual acuity; one or two mistakes per line are allowed. When the subject has difficulty reading a letter, he is encouraged to guess. Changes in visual acuity over time are generally reported in units of "Number of lines gained or lost." Other methods of recording visual acuity may be used for individual clinical trial protocol. ETDRS Illuminator Cabinet Illumination standards for visual acuity testing were set by the first major clinical trial. This retro-illuminated cabinet has a LUX of 750. Each cabinet is set up with 2 fluorescent lamps, each lamp then has a fenestrated sleeve (diffuser). Replacement of the lamp is simple and the diffuser can be reused. The cabinet has storage in the back for quick chart access. A 5- leg caster base can be obtained for mobility. |
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OUR ADDRESS: SUSSEX VISION 16 WINSTON BUSINESS
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