Retinal Embolization after Carotid Artery Stenting in a Monocular Patient: Clinical and Ethical Implications

Severe carotid artery narrowing is a well-recognized cause of ischemic stroke, and carotid artery stenting (CAS) is frequently used to restore blood flow and prevent recurrence. Although embolic protection devices are designed to reduce the risk of distal embolization, ocular complications can still occur. When treating patients with vision in only one eye, any compromise in ocular circulation can have devastating consequences. A 63-year-old male presented with an acute ischemic stroke caused by severe narrowing of the Right internal carotid artery. He underwent CAS. Shortly after the procedure, he developed a sudden diminution of vision in his right eye - the only functional eye, as he had been blind in the left eye since childhood due to trauma. Ophthalmologic evaluation revealed a supratemporal branch retinal artery occlusion. Despite prompt medical management, visual recovery was minimal. This case illustrates the clinical and ethical challenge of managing cerebrovascular disease in patients at high risk of total blindness. This case highlights that retinal embolization can occur during carotid stenting and emphasizes the importance of careful patient selection, procedural vigilance, and thorough preoperative counseling - especially in individuals with monocular vision. Balancing the benefits of stroke prevention with the risk of irreversible vision loss requires a multidisciplinary and patient-centered approach.