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Developing a clinically viable protocol for measuring and analysing the human contrast sensitivity function on a standard computerised chart

Purpose Contrast sensitivity testing is an important part of visual assessment and can identify visual deficits that go undetected by measuring visual acuity (VA) alone. Despite this, contrast sensitivity testing is rarely performed clinically due to the expensive processes required and limited test availability, with few spatial frequencies used. Further, gratings can be difficult for subjects to learn and results are often not standardized. We developed and tested a convenient, inexpensive protocol using Snellen optotypes to measure the CSF using a widely available computerised VA chart. Effects of blur and neutral density (ND) light attenuation were analysed to evaluate the technique under different conditions.