Optical coherence tomographic assessment of dynamic macular changes in patients with Vogt-Koyanagi-Harada disease.

To determine the relationship between visual acuity and three-dimensional optical coherence tomographic (3D-OCT) findings of the macula in eyes with Vogt-Koyanagi-Harada (VKH) disease. Twelve eyes of six patients (three men and three woman, average age 53.2 years) in the acute phase of VKH disease were examined with a 3D-OCT instrument. All of the eyes had a serous macular detachment. The height of the sensory retinal detachment (SRD) and the sensory retinal thickness (SRT) were measured by OCT before treatment (acute stage) and at the convalescent stage. The correlation between the retinal morphology and visual acuity was evaluated. The height of the SRD and the SRT were 612.5 ± 371.2 and 136. 7 ± 22.0 µm, respectively. The initial visual acuity was significantly worse in eyes with a higher SRD (P = 0.014, r = 0.68) but the correlation between initial visual acuity and SRT was not significant. The recovery of visual acuity was attained in 50.7 ± 44.1 days and the complete resolution of the SRD was attained in 30.5 ± 23.2 days. The final visual acuity was attained several days after the complete resolution of the SRD in all four eyes of patients over 60 years of age, but the recovery of visual acuity often preceded the complete resolution of the SRD. The OCT images provided a noninvasive indicator of the severity of the disease and dynamic changes in the macular morphology, reflecting the effect of treatment in association with the improvement in visual acuity. Monitoring the SRD by 3D-OCT may guide the tapering of systemic corticosteroid treatment.

Rod-driven focal macular electroretinogram.

PURPOSE: To determine the stimulus conditions required to elicit rod-driven, focal macular electroretinograms (rod FMERGs). METHODS: A blue (lambda(max)=470 nm) stimulus, 5 degrees in size, was imaged at a luminance of 1.5 cd/m(2) on different regions of the human retina. Electroretinograms (ERGs) elicited by this stimulus were recorded from the light- and dark-adapted retina of four subjects without any ophthalmological abnormalities. A subject with cone dystrophy was also tested by this method. RESULTS: Stimulus luminance <==1.5 cd/m(2) did not elicit a response when it was imaged on the optic disc, but higher intensities elicited a small b-wave from stray light. When this stimulus was imaged on the macular area or the 15 degrees temporal retina, an ERG was elicited that had the shape of the full-field scotopic ERG. This stimulus with a luminance of 1.5 cd/m(2) did not elicit a response from stimulation of the macular area of a light-adapted retina but elicited a slow-rising positive b-wave after 30 minutes of dark adaptation. In a subject with cone dystrophy, focal rod response was elicited from the macula, despite no response under photopic conditions. CONCLUSION: We conclude that this stimulus will elicit a response that is derived exclusively from rods and is a focal response with no contribution from stray light.