THE ACUTE AND LONG-TERM OCULAR EFFECTS OF ACCELERATED HYPERTENSION - A CLINICAL AND ELECTROPHYSIOLOGICAL STUDY

Thirty-four patients with accelerated hypertension were clinically exa mined, The visual evoked potential (VEP) and electroretinogram (ERG) w ere recorded: acutely in 12 patients, being repeated in 7 patients up to 6 months later, In the remaining 22 patients these tests were perfo rmed 2-4 years after presentation, Visual acuity was less than or equa l to 6/12 in 22 of 68 (32%) eyes at presentation and less than or equa l to 6/12 in 10 of 58 (19%) eyes at follow-up, The cause of severest l oss of vision appeared to be anterior ischaemic optic neuropathy, foun d in 3 cases, During the acute stage 11 patients (92%) had abnormal VE Ps and all had abnormal ERGs, The group mean P100 latency, of the 7 pa tients (14 eyes) seen acutely and followed up at 6 months, was 123.8 m s with significant recovery of latency (p<0.005) to 110.9 ms, The ERGs , however, remained reduced and delayed, In those patients recorded 2- 4 years after their acute episode the VEP was abnormal in only 2 patie nts (9%); group mean P100 latency was 109.1 ms, However, 18 patients ( 82%) had abnormal ERGs, We suggest that during the acute stage of acce lerated hyertension there is a high incidence of ischaemic optic neuro pathy that usually resolves but can cause a permanent anterior ischaem ic optic neuropathy, in addition to vascular retinopathy that persists .