Clinical and electrophysiological observations in patients with low pressure retinopathy.

The clinical, angiographic, and electrophysiological features of seven patients with transient visual loss and low-pressure retinopathy are presented. Six of the patients also had symptoms of cerebral ischaemia. The commonest provoking feature was bright light. Angiography showed multiple extracranial occlusions involving both internal and external carotid arteries in addition to occlusion or stenosis on the contralateral side. Electroretinography showed delay in the recovery of the b wave in the affected eye after exposure to bright light. This appears to be a valuable test for the detection of minor degrees of ischaemic damage to the retina caused by insufficiency of the retinal and choroidal circulation.