Glaucomatous-Like Optic Neuropathy Due to Compression of the Optic Nerve by the Internal Carotid Artery

Compression of the optic nerve by the supraclinoid internal carotid artery (ICA) has long been recognized as a potential cause of an optic neuropathy. Visual field defects and optic nerve cupping resembling glaucoma were surprisingly found in a previous case series.[1] We describe 3 patients with radiological ICA compression of the optic nerve without elevated intraocular pressure (IOP)and a phenotype that resembled glaucoma. All patients had preserved visual acuity (VA), color vision, glaucomatous visual field defects, cupping without pallor, open angles, unilateral disease and a normal IOP. They were referred to neuro-ophthalmology due to low IOP or progression despite low IOP.