Delayed-onset homonymous hemianopia following stent assisted coil embolization of a large internal carotid artery bifurcation aneurysm; case report and review of the literature

Abstract We present the case of a 78-year-old patient with a large right internal carotid artery aneurysm found incidentally after 2-weeks of blurry vision without headache. The patient underwent endovascular coiling of the aneurysm with flow diverting stent placement for vessel reconstruction. The patient developed a left homonymous hemianopia two weeks after treatment. Magnetic resonance imaging demonstrated aneurysm expansion with perianeurysmal edema in the thalamus, basal ganglia and mild compression of the optic chiasm. The patient was started on high dose dexamethasone and his vision slowly improved over the next several months. This is a rare case of expansion of a coiled large cerebral aneurysm with mass effect on the anterior visual pathway.