Two-stage hybrid management of a distal internal carotid mycotic aneurysm in a young adult: A case report

Type IV carotid artery aneurysms are uncommon; mycotic variants are rarer and challenging. We report a distal internal carotid aneurysm managed with a two-stage hybrid approach. A 28-year-old man had an enlarging left cervical mass with transient dysphagia and dysphonia. CT showed a distal internal carotid aneurysm measuring 71 × 49 mm, extending to the pre-foraminal segment. FDG-PET/CT demonstrated avid uptake (SUV 8.9). Work-up excluded endocarditis; Quantiferon was positive. Multidisciplinary review deemed endografting unsuitable and bypass unsafe given absent distal control. Under local anesthesia, a 50-minute balloon occlusion test of the petrous internal carotid artery was followed by coil embolization and proximal vascular plug, completing arterial sacrifice. Post-procedure transient monocular visual loss corresponded to a small watershed infarct; hemodynamic augmentation achieved full recovery within 24 hours. Six days later, aneurysmectomy was performed with ligation of the common and external carotid arteries. Cultures grew Cutibacterium acnes ; clindamycin then six weeks of amoxicillin were given. The patient was discharged day seven. At day 22 the wound had healed, dysphonia improved, and inflammatory markers fell without new neurologic events. When anatomy precludes reconstruction, staged sacrifice after a successful balloon occlusion test can enable definitive aneurysmectomy while preserving cerebral perfusion.