The optic disc in glaucoma, III: diffuse optic disc pallor with raised intraocular pressure.

Ten patients (14 eyes) with chronic simple glaucoma are described, each with features atypical for this disease and more suggestive that each had suffered an acute ischaemic optic neuropathy. Diagnosis of an acute ischaemic optic neuropathy in these cases is important, as treatment of ocular hypertension in the contralateral 'normal' eye may prevent a similar attack. Optic nerve disease and visual loss in chronic simple glaucoma probably occur as a result of several different mechanisms. Sudden field loss following an acute ischaemic optic neuropathy may be only one of them.