RESUMO
PURPOSE: To present an example of how close clinical monitoring of a patient with acute Horner syndrome from carotid artery dissection may be critical in reversing neurologic dysfunction. OBSERVATIONS: A patient whose initial neuro-ophthalmic manifestation was Horner syndrome, but who evolved over 14 days to display transient monocular vision loss, ipsilateral ocular ischemic syndrome, and episodic contralateral hemiparesis. Digital subtraction angiography demonstrated progressive ipsilateral carotid occlusion with lack of collateral flow. The patient underwent stenting with rapid reversal of transient monocular visual loss and hemiparesis. Follow-up examination several months later confirmed complete resolution of all clinical abnormalities. CONCLUSIONS AND IMPORTANCE: This case displayed protracted evolution of ischemic manifestations following carotid artery dissection and their prompt reversal with stenting. This case emphasizes the value of close clinical attention to a patient with acute Horner syndrome because manifestations may appear more than 10 days after event onset that impel intervention for the dissection.