Figure 2. Visual function data

ERG and Goldmann visual fields on BCM affected brothers IV-3 and IV-4. Xenon-flash Ganzfeld ERGs used standard conditions [28] with fully dilated pupils and Burian-Allen bipolar corneal electrodes (Hansen Ophthalmic Instruments). Subjects were dark-adapted for 45 minutes before the scotopic rod ERG was elicited with -1.86 log cd-sec/m². Cone responses were isolated with 30 Hz flicker (4.2 cd-sec/m²/flash) and by photopic adaptation of 3.3 log scotopic trolands and "white" flashes of 1.0 log cd-sec/m². Flicker tracings are computer averaged from 10 responses, others are single flash responses. Two responses for each test condition are shown for the normal and for IV-3; single tracings are shown for IV-4. The "Normal" responses are from an unaffected individual with amplitudes and wave forms conforming approximately to our population norms.