When the Eagle Strikes the Carotid: A Case Report of Carotid Artery Dissection Secondary to Eagle Syndrome.

Eagle syndrome, characterized by elongation of the styloid process or calcification of the stylohyoid ligament, is a rare but clinically significant cause of carotid artery dissection and ischemic stroke that is frequently overlooked, particularly in younger patients without traditional cerebrovascular risk factors. We report the case of a 45-year-old right-handed man with no significant past medical history other than tobacco use who presented with acute-onset expressive aphasia and right hemiparesis following weight lifting. Initial neuroimaging revealed a left middle cerebral artery (MCA) territory infarct with occlusion of a distal M2 branch and left cervical internal carotid artery (ICA) occlusion suspicious for dissection. He was treated with intravenous tenecteplase and admitted to the neurological ICU. An extensive etiological workup, including echocardiography, cardiac rhythm monitoring, hypercoagulable studies, and cerebrospinal fluid analysis, was unremarkable. Computed tomography angiography (CTA) demonstrated bilateral elongation of the styloid processes, measuring approximately 5 cm each, with the left styloid process directly abutting the cervical ICA at the level of dissection, establishing Eagle syndrome as the underlying etiology. The patient subsequently underwent contralateral prophylactic styloidectomy following stabilization. This case highlights the importance of considering Eagle syndrome in the differential diagnosis of carotid artery dissection and ischemic stroke in young adults; careful review of neurovascular imaging, including assessment of styloid process morphology, is essential for timely diagnosis and prevention of recurrent cerebrovascular events.