The comprehensive low vision examination includes the evaluation of distance and near visual acuity, refraction, determination of the integrity of the peripheral and central visual field, brightness acuity and contrast sensitivity.
These data reveal an individual's potential response to optical devices, and the likelihood that magnification, illumination, contrast, or other clinical parameters may need to be altered for successful device instruction and prescription. Specialized charts necessary for low vision testing of adults and children come in single-letter, single-number or single-symbol form, in single word and continuous text in multiple languages.
The most widely used tests feature Sloan optotypes arranged in LogMar progression. The ability to vary the test distance is important in low vision care and is a feature of rolling and hand-held charts.