The acute and long-term ocular effects of accelerated hypertension: a clinical and electrophysiological study.

Thirty-four patients with accelerated hypertension were clinically examined. The visual evoked potential (VEP) and electroretinogram (ERG) were recorded: acutely in 12 patients, being repeated in 7 patients up to 6 months later. In the remaining 22 patients these tests were performed 2-4 years after presentation. Visual acuity was < or = 6/12 in 22 of 68 (32%) eyes at presentation and < or = 6/12 in 10 of 58 (19%) eyes at follow-up. The cause of severest loss of vision appeared to be anterior ischaemic optic neuropathy, found in 3 cases. During the acute stage 11 patients (92%) had abnormal VEPs and all had abnormal ERGs. The group mean P100 latency, of the 7 patients (14 eyes) seen acutely and followed up at 6 months, was 123.8 ms 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 patients (9%); group mean P100 latency was 109.1 ms. However, 18 patients (82%) had abnormal ERGs. We suggest that during the acute stage of accelerated hypertension there is a high incidence of ischaemic optic neuropathy that usually resolves but can cause a permanent anterior ischaemic optic neuropathy, in addition to vascular retinopathy that persists.