Indication of Flow Diverter Therapy for Unruptured or Chronically Ruptured Large or Giant Cerebral Aneurysms Located in the Internal Carotid Artery

Abstract

We retrospectively reviewed 131 patients with 136 unruptured, or chronically ruptured, large or giant cerebral aneurysms located in the internal carotid artery (ICA). All the aneurysms were treated with flow diverter (FD) therapy using the PIPELINE embolization system. We focused on analyzing the clinical and anatomical results of our 2-year clinical and radiological follow-ups. Only two patients (1.5%) showed clinical deterioration on the modified Rankin scale (mRS) ＞0. Radiological examinations revealed complete aneurysm occlusions in 77.9% of cases. Factors that were predictive of incomplete aneurysm occlusions were aneurysms that were extremely large or giants, very wide necks, and elderly patients. An associated coil embolization was a predictive factor for a complete aneurysm occlusion. Regarding cranial nerve palsy due to compression by an aneurysm, the oculomotor and abducens nerve palsies tended to recover better than did those of the optic nerve. FD therapy is, therefore, the first treatment of choice for unruptured or chronically ruptured large or giant intracranial ICA aneurysms. Associated coil embolization may be recommended when patients have factors that are predictive of incomplete aneurysmal occlusions. Patients requiring immediate and certain resolution of aneurysmal mass effects should consider a risk-benefit assessment of FD therapy, parent artery occlusion, and open surgery.