Spaeth/Richman Contrast Sensitivity Test

Contrast Sensitivity is another way to test vision. It uses black on a white background and minimally decreases the black (grey) until it blends with the white. The least amount of contrast (faint grey) seen translates into amount of vision. This new method of determining contrast sensitivity uses black and white vertical bars and does not require recognizing letters in the alphabet. It tests various areas of the visual field and central vision. The test takes approximately 3 minutes per eye. Pelli-Robson is a commonly used contrast sensitivity test that uses black letters on a white background. The letter size stays the same, only the amount of black changes, becoming greyer, making letters hard to see. The test takes approximately 1 minute per eye. Hypothesis: A method of determining contrast sensitivity that does not require letter recognition (as does the Pelli-Robson test) eliminates the barriers of literacy and pattern recognition, to permit a more valid determination of contrast sensitivity. Patients will perform SPARCS and Pelli-Robson twice; once each with two separate observers for reproducibility and intra-observer reliability. The order of testing will be randomized to SPARCS, Pelli, Pelli, SPARCS or Pelli, SPARCS, SPARCS, Pelli.