Bitemporal hemianopsia secondary to ischemic chiasmopathy following mechanical thrombectomy

Purpose: To report a case of bitemporal hemianopsia due to ischemic chiasmopathy after mechanical thrombectomy of a right distal internal carotid artery (ICA) occlusion. Observations: A 60-year-old female presented with left sided weakness and difficulty speaking and was found to have suffered a right internal carotid artery occlusion 10 days after tricuspid valve replacement for severe symptomatic tricuspid valve disease. She underwent mechanical thrombectomy and in hospital and at further follow ups was noted to have a bitemporal hemianopsia, consistent with an ischemic optic chiasmopathy. Conclusions and importance: The optic chiasm is vascularized by multiple arteries of the Circle of Willis. As such, ischemic optic chiasmopathy is rare. Clinicians should consider ischemic chiasmopathy following cardiac and other surgical procedures including mechanical thrombectomy of the ICA or its branches.