Optic Pathway Action Potentials and Intraocular Pressure (IOP) Rise

Abstract

Before the occurrence of visual field losses, the visual evoked potential (VEP) in patients with open angle glaucomatous disease (OAG) may be disturbed. In OAG-patients pharmacological lowering of systemic blood pressure can result in a decrease of the VEP amplitude. Prior systemic lowering of IOP, however, does not always result in improvement of the VEP response.

Inadequate capillary perfusion under conditions of elevated IOP threatens axonal function of the optic pathway. Conditions of diseased vessel wall also threaten axonal function. Experimental animal models confirm these clinical findings. Repeated IOP increases cause permanent lowering of action potentials, released only by increasing the systemic blood pressure.