Understanding the spectrum between orbital infarction syndrome and secondary orbital inflammation following endovascular thrombectomy: a case series

BACKGROUND: Orbital infarction syndrome (OrbIS) is a rare but devastating complication following mechanical thrombectomy for ischemic stroke, characterized by a near-global ischemia of intraocular and orbital tissues. It can mimic a more benign secondary orbital inflammation (SOIN), leading to diagnostic uncertainty. We present the largest case series of seven patients who developed acute periorbital swelling following endovascular thrombectomy (EVT) for anterior circulation large vessel occlusion with clinically diagnosed OrbIS or SOIN. METHODS: A retrospective review of our EVT database was performed and patients who developed these orbital complications were identified. Clinical features, angiographic findings, and outcomes were analyzed, and a literature review was performed to contextualize our findings. RESULTS: Out of 1179 patients, four patients were diagnosed with OrbIS and three with SOIN. Patients with OrbIS usually presented within the first 12 hours following EVT and had irreversible vision loss, while those with SOIN had a more delayed onset and good visual recovery. The pathophysiologic spectrum may reflect differing degrees of ischemia, collateral compromise, and secondary inflammatory or reperfusion-related injury. CONCLUSIONS: Orbital complications following thrombectomy represent a spectrum from complete ischemia with poor outcomes to secondary transient inflammation with good outcomes. Early recognition, prompt ophthalmic consultation, and interdisciplinary management are crucial for optimizing outcomes.