title: Endovascular treatment of peripheral aneurysms of the posterior inferior cerebellar artery.
abstract: OBJECTIVE
  Peripheral aneurysms of the posterior inferior cerebellar artery (PICA) are rare, and pre-existing literature concerning their endovascular treatment is limited. The purpose of this study was to assess the etiology and clinical characteristics of peripheral PICA aneurysms and to evaluate the angiographic and clinical results of the patients who underwent endovascular treatment for a peripheral PICA aneurysm in a single center.
  
  
  METHODS
  Twelve consecutive patients with 12 peripheral PICA aneurysms (10 ruptured) included in an internal data base were retrospectively reviewed. Posttreatment and follow-up angiograms were analyzed, and the clinical outcome was recorded.
  
  
  RESULTS
  The etiology was dissection in 7 (58%) and unknown in 5 cases (42%). Three dissecting aneurysms reruptured before endovascular treatment, and another 3 demonstrated angiographic progress. Four aneurysms were treated by endosaccular coiling, 6 (all dissecting) by parent artery occlusion, and in 2 cases endovascular treatment failed. Angiographic outcome was complete aneurysm and/or parent artery occlusion in 9 cases and neck remnant in 1 case. One aneurysm needed retreatment at follow-up. One lethal procedural complication occurred, and transient ischemic symptoms appeared in 2 patients. The clinical outcome was good in 7 patients, whereas 3 patients, all poor clinical grade, died (1 for unrelated reasons). No rebleedings have occurred during the follow-up.
  
  
  CONCLUSIONS
  In this series, most peripheral PICA aneurysms were secondary to arterial dissection. They were unstable with a high risk of rebleeding and a high mortality if not treated without delay. Endovascular treatment was effective in preventing rehemorrhage.
authors.affiliation: Department of Radiology, Oulu University Hospital, Oulu, Finland. matti.isokangas@ppshp.fi
authors.forename: J-M
authors.initials: JM
authors.lastname: Isokangas
authors.forename: T
authors.initials: T
authors.lastname: Siniluoto
authors.forename: T
authors.initials: T
authors.lastname: Tikkakoski
authors.forename: T
authors.initials: T
authors.lastname: Kumpulainen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000784:Aortic Dissection / Q000000981:diagnostic imaging / Q000401:mortality / Q000628:therapy*; D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging / Q000401:mortality / Q000628:therapy*; D000800:Angioplasty, Balloon; D001158:Arteries; D002531:Cerebellum / Q000098:blood supply*; D002533:Cerebral Angiography; D004621:Embolization, Therapeutic; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000401:mortality / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012008:Recurrence; D019233:Retreatment; D012189:Retrospective Studies; D015996:Survival Rate