A COMPARISON OF THE OPTICAL STILES-CRAWFORD EFFECT AND RETINAL DENSITOMETRY IN A CLINICAL SETTING

PURPOSE. To compare the measurement(2) of the optical Stiles-Crawford effect (SCE) to the densitometry of cone visual pigments in a clinical setting. Both tests provide information on outer retinal integrity, b ut the optical SCE can be performed in far less time. METHODS. Images acquired with a custom-built scanning laser ophthalmoscope were used t o assess visual pigment density and optical SCE. Visual pigment densit y was regarded as the ''gold standard.'' More than 100 patients with s uspected, and some with known, outer retinal pathology were tested. Th e group included cases of central serous detachment, cone dystrophy, S targardt's disease, Best's disease, and retinitis pigmentosa. RESULTS. Parameters of the optical SCE of 25 healthy subjects and 106 patients were taken through a stepwise linear regression to predict density. T he correlation be tween predicted density from the optical SCE and the measured density was 0.82. The sensitivity of the optical SCE to dete ct decreased density was 96%. When only the foveal reflectance was con sidered, sensitivity was still 84% CONCLUSIONS. The optical SCE is a s ensitive and fast method for detecting cone photoreceptor disturbances .