The Effects Of The Trial Lens In Threshold Automated Perimetry.

Fourteen normal dilated right eyes were tested using a custom designed threshold test of the Humphrey Visual Field Analyzer (Humphrey Instruments, San Leandro, California) to
determine the importance of the trial lens used as the add. Two factors used to determine the importance of the add were test reliability and retinal sensitivity. The custom designed program consisted of eleven randomly chosen points in the central thirty degrees of the visual field. The program was performed five times on each subject, once using the suggested value for the add, and then above and below this null point in 2.00 diopter
steps. This study indicates that both reliability and overall retinal sensitivity are decreased when an improper add is used.