LAUSR

A previously healthy 20-year-old man developed acute visual field loss followed by a severe headache, dizziness, and nausea that resolved after few hours. The patient presented to the emergency department 10 hours later. Ophthalmic examination showed a visual acuity of 20/20 in each eye (both eyes). The pupils were normally reactive in both eyes, and there was no anisocoria or relative afferent pupillary defect. Automated perimetry (Humphrey visual field) showed a right congruous and vertical meridian sparing homonymous hemianopia (Fig. 1A, B). The remainder of the eye examination was normal in both eyes. A computed tomography scan of the head without contrast showed hypodensity in the left occipital region. MRI scan of the brain including diffusion-weighted imaging (DWI) showed a subacute posterior cerebral artery (PCA) ischemic stroke of the left medial occipital lobe, splenium of the corpus callosum, and dorsal left thalamus (Fig. 2). A full neurologic examination was normal. Cardiac evaluation showed a right-to-left shunt through a patent foramen ovale (PFO), and he was started on dual antiplatelet therapy and a statin medication. Two months later, he underwent endovascular cardioform occlusion therapy to close the PFO. The remainder of the stroke evaluation was unremarkable including carotid, hypercoagulable state, and vasculitis evaluation. The visual field defect remained stable, the patient developed no recurrent symptoms or signs, and he was referred to low-vision rehabilitation.