Purpose:
Clinical tests of contrast sensitivity are performed at near with letters large enough to
be above the acuity threshold of presbyopes with normal vision. Is a reading addition necessary to obtain accurate thresholds?
Method:
Contrast sensitivity was assessed using Pelli-Robson and Mars charts. Participants were presbyopes with normal or corrected-to-normal distance and near acuity.
Contrast sensitivity was assessed with participants wearing distance refractive
correction, and also wearing an appropriate addition for the working distance (+0.75DS for the Pelli-Robson at 1m; +2.00DS for the Mars at 50cm).
Results:
The difference between contrast sensitivity measurements made with and without the reading addition was not signifi cant for either chart (repeated measures t-test,
p>0.05 for Pelli-Robson and Mars).
Conclusion:
Contrast sensitivity can be assessed in presbyopic visual normals with patients wearing either distance or near correction without affecting thresholds
