Non-arteritic anterior ischemic optic neuropathy associated with ipsilateral hypoplastic internal carotid artery.

Abstract

Vascular insufficiency of the optic nerve head is the cause of non-arteritic ischemic optic neuropathy (NAION). Carotid artery abnormalities are now considered as a predisposing factor for developing NAION. In this report, we present a case of NAION associated with ipsilateral internal carotid artery hypoplasia. A 69-year-old female was referred for evaluating the cause of vision loss in her left eye. The patient was diagnosed with left NAION, however, the magnetic resonance imaging (MRI) showed a considerably smaller left internal carotid artery (ICA) than the right side. The magnetic resonance angiography (MRA) confirmed the disparity as well as perfusion abnormalities of intracranial carotid arteries. The diagnosis of left ICA hypoplasia was made and verified by depicting a left side small carotid canal on the computed tomography (CT) scan. This report suggests that ICA hypoplasia could be associated with NAION.