Optic disc edema in raised intracranial pressure. VI. Associated visual disturbances and their pathogenesis
S. S. Hayreh
The pattern and pathogenesis of nonlocalizing visual disturbances,
associated with optic disc edema (ODE). raised cerebrospinal fluid
pressure, and intracranial space-taking lesions were investigated
experimentally in rhesus monkeys with simulated progressive brain tumor and
clinically in patients with benign intracranial hypertension. The visual
disturbances occurring in one of both eyes were of three types: recurrent
attacks of transient obscuration, permanent blindness, and various types of
visual field defects. The studies indicate that the visual disturbances are
usually due to two mechanisms. The most common is ischemia of the optic
disc secondary to ODE. The other, rarer mechanism probably consists of the
space-taking lesion causing downward herniation of the parahippocampal
gyrus into the tentorial notch, producing compression of the lateral
geniculate body and optic tract.
