title: [A de novo distal PICA aneurysm occurring 3 years after clipping of another distal PICA aneurysm: a case report].
abstract: Distal posterior inferior cerebellar artery (dPICA) aneurysms are rare with an incidence of approximately 1% of all intracranial aneurysms. The frequent reports of the non-branching aneurysms or tandem aneurysms in an identical artery may be related to the embryology of dPICA and the anterior inferior cerebellar artery which is distinct from other cerebral arteries, as characterized by a thin vessel wall and tortuous course. In this paper, the authors present a case of a 67-year-old man with a ruptured de novo dPICA aneurysm in the tonsillomedullary segment, which occurred 3 years after clipping of a ruptured aneurysm in the identical segment of the dPICA. The patient had a history of smoking and uncontrolled hypertension. He presented with a sudden onset of severe headache and vomiting. On admission computed tomography demonstrated subarachnoid hemorrhage in the left cerebello-medullary cistern with intra-forth ventricular clots. Vertebral angiography demonstrated a saccular dPICA aneurysm just distal from the previous clip. Based on the angiographic characteristics of the aneurysm and the potential difficulty of a second clipping operation, coil embolization of the parent artery was performed. The postoperative course was uneventful except for the presence of hoarseness. The unusual development and location of ruptured de novo dPICA aneurysm may be explainable by uncontrollable risk factors, as well as by the embryological features of dPICA. Careful follow-up neuroimaging studies and management of risk factors should be continued even after complete neck clipping or coil embolization in cases of dPICA aneurysm.
authors.affiliation: Department of Neurosurgery, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki-shi, Osaka 569-8686, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Hirota
authors.forename: Naokado
authors.initials: N
authors.lastname: Ikeda
authors.forename: Yoji
authors.initials: Y
authors.lastname: Tamura
authors.forename: Kunio
authors.initials: K
authors.lastname: Yokoyama
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Yamada
authors.forename: Terumasa
authors.initials: T
authors.lastname: Kuroiwa
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Kuroiwa
mesh_terms: D000368:Aged; D017542:Aneurysm, Ruptured / Q000601:surgery; D002533:Cerebral Angiography; D004621:Embolization, Therapeutic; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery* / Q000628:therapy; D008297:Male; D011183:Postoperative Complications; D014057:Tomography, X-Ray Computed