PATTERN-REVERSAL VISUAL-EVOKED RESPONSE IN BULLS EYE MACULOPATHY ASSOCIATED WITH STARGARDTS-DISEASE

Using steady-state pattern-reversal visual-evoked response (PVER), we studied the macular function in patients with bull's eye maculopathy. The results were correlated with fluerescein angiography. Study patien ts with an established (25 eyes of 14 patients) and a suspected (8 eye s of 4 patients) diagnosis of Stargardt's disease with bull's eye macu lopathy were divided into group G (good vision group: 15 eyes with vis ual acuity of 20/40 or better) and group P (poor vision group: 18 eyes with visual acuity of 20/50 or worse). The diameters of the atrophic area and the normal or less affected central area of the bull's eye we re measured from the fluorescein angiograms. The mean diameter of the central area in group G (2.0 degrees) was significantly larger than th at in group P (0.6 degrees; d.f. = 17, p = 0.0227). The PVER amplitude s were reduced in the patient groups with all check sizes and the ampl itude-check size functions were flat. Amplitude differences were obser ved between the patient groups with the 20' checks (d.f. = 17, p = 0.0 638), probably due to the difference in the mean central diameters (2. 0 degrees vs. 0.6 degrees). Patients with a perifoveal abnormality can have an abnormal PVER despite relatively good visual acuity. We also recorded the PVER in 7 normal controls tested with simulated ring-shap ed scotomas, the sizes of which matched the mean diameters of the scot omas in the patient groups (7.0 degrees x 0.6 degrees and 7.0 degrees x 2.0 degrees). The controls also showed markedly reduced responses wi th all check sizes. With the 10-min check, a significant difference wa s seen between controls tested with the two scotoma sizes, simulating the two patient groups. The amplitude-check size function in bull's ey e maculopathy flattened even in those whose vision was relatively good .