The effect of refraction accuracy on the differential light treshold of a Goldmann size III (0.43° diameter) stimulus was evaluated in the right eyes of five normal subjects with randomly ordered sequence of plano, +1.00-, +2.00-, +3.0-, +4.00-, +5.00-, and +6.00-diopter (D) spherical overcorrections. Threshold measurements were performed at 0°, 5°, 10°, 15°, 20°, and 25° eccentricity nasally along the 180° meridian with the F4 program on the Octopus 201 perimeter. The +1.00- through +6.00-D overcorrections decreased the threshold values by an average of 1.4, 2.9, 4.2, 5.6, 6.7, and 7.6 dB, respectively, compared with the plano overcorrection. The depression of the differential light threshold was of similar magnitude at all eccentricities within the central 25°.
- automated threshold perimetry
- differential light threshold
- threshold measurements
- threshold perimetry
ASJC Scopus subject areas