title: Distal posterior inferior cerebellar artery aneurysms: clinical features and outcome of 80 patients.
abstract: OBJECTIVE
  Aneurysms of the posterior inferior cerebellar artery (PICA) distal to its origin are rare. Beside their rarity, their treatment is challenged by a high proportion of fusiform aneurysms, torturous course of PICA, and often severe bleeding. Our aim is to represent the characteristics of these aneurysms and their treatment, as well as to analyze outcome.
  
  
  METHODS
  We reviewed retrospectively 80 patients with PICA aneurysms who were treated at the Department of Neurosurgery, Helsinki, Finland.
  
  
  RESULTS
  The 80 patients had altogether 91 distal PICA aneurysms. Subarachnoid hemorrhage occurred in 74 (93%), and the distal PICA aneurysm was ruptured in 68 (85%). Compared with aneurysms at other locations, distal PICA aneurysms were smaller, more often fusiform, and more often caused an intraventricular hemorrhage as well as rebleeding. Modified surgical techniques (trapping, wrapping, proximal occlusion, resection, coagulation) were used in 10 (32%) fusiform and in 3 (6%) saccular aneurysms. Revascularization was needed in 3 (4%) cases. One aneurysm was primarily embolized. Within a year after aneurysm diagnosis, 18 patients had died. Among survivors, most returned to independent or previous state of living: 52 (91%); only 1 patient was unable to return home.
  
  
  CONCLUSIONS
  Microsurgery is a feasible treatment for distal PICA aneurysms. Despite the challenge of often severe hemorrhage, wide-necked aneurysms, and some risk for laryngeal palsy, most patients surviving the initial stage return to normal life. Because of the greater number of rebleedings than for aneurysms at other locations, immediate treatment is crucial.
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland. Electronic address: hanna.lehto@hus.fi.
authors.forename: Hanna
authors.initials: H
authors.lastname: Lehto
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Ali
authors.initials: A
authors.lastname: Harati
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Mika
authors.initials: M
authors.lastname: Niemelä
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Reza
authors.initials: R
authors.lastname: Dashti
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Aki
authors.initials: A
authors.lastname: Laakso
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Elsharkawy
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Jarno
authors.initials: J
authors.lastname: Satopää
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Romain
authors.initials: R
authors.lastname: Billon-Grand
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Bruno
authors.initials: B
authors.lastname: Canato
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Riku
authors.initials: R
authors.lastname: Kivisaari
authors.affiliation: Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland.
authors.forename: Juha
authors.initials: J
authors.lastname: Hernesniemi
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D017542:Aneurysm, Ruptured / Q000401:mortality / Q000601:surgery*; D002531:Cerebellum / Q000098:blood supply; D002548:Cerebral Revascularization / Q000379:methods* / Q000401:mortality; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D002538:Intracranial Arteriovenous Malformations / Q000401:mortality / Q000601:surgery; D008297:Male; D008866:Microsurgery / Q000379:methods* / Q000401:mortality; D008875:Middle Aged; D011379:Prognosis; D020127:Recovery of Function; D012189:Retrospective Studies; D013345:Subarachnoid Hemorrhage / Q000401:mortality / Q000601:surgery*; D016896:Treatment Outcome; D014711:Vertebral Artery / Q000002:abnormalities / Q000601:surgery; D055815:Young Adult
keywords: Cerebral aneurysm; Microsurgery; Posterior inferior cerebellar artery; Vertebral artery