title: Endovascular treatment of posterior circulation cerebral aneurysms by using Guglielmi detachable coils: a 10-year single-center experience with special regard to technical development.
abstract: OBJECTIVE
  The purpose of this study was to analyze the immediate and long-term angiographic and clinical results of endovascular treatment of posterior circulation aneurysms with special regard to technical development.
  
  
  METHODS
  Between 1993 and 2003, 46 patients with 47 aneurysms of the posterior circulation were referred to our institution for endovascular treatment. Mean angiographic follow-up was 1.7 years. Clinical follow-up was determined at hospital discharge and by using a questionnaire for long-term follow-up (mean, 3.3 years). To analyze technical development, patients treated before (group 1) and after (group 2) implementation of 3D Guglielmi detachable coils (3D GDCs) in 1999 were compared. Multivariate analysis was performed to determine factors predictive of clinical and technical outcome.
  
  
  RESULTS
  Overall, at initial treatment complete occlusion was achieved in 27 (57.4%) aneurysms, a neck remnant was present in 16 (34.0%) aneurysms, incomplete occlusion was achieved in 3 (6.4%) aneurysms, and in 1 (2.1%) case occlusion was not attempted. Procedure-related permanent morbidity was 4.3%, and the mortality rate was 0%. There was no rebleeding of treated aneurysms. Complete occlusion at initial treatment (P = .003) and recanalization rate (P = .008) correlated with aneurysm sac size. A statistically significant relationship between Hunt and Hess/World Federation of Neurologic Surgeons clinical grading scale score and clinical outcome (Glasgow Outcome Score) was found (P < .05). Subgroup analysis revealed that a higher initial obliteration rate of larger aneurysms was achieved in group 2 (3D GDC, 22 patients, 22 aneurysms) than in group 1 (23 patients, 24 aneurysms; P = .03). At angiographic follow-up, overall recanalization was 47.1% in group 2 and 47.6% in group 1. Aneurysm neck size was not found to be correlated with occlusion and recanalization rate.
  
  
  CONCLUSIONS
  In our series, GDC technology was an effective and safe technique for the treatment of posterior circulation aneurysms. Aneurysm sac size was predictive for occlusion rate and the Hunt and Hess/World Federation of Neurologic Surgeons grade for clinical outcome. The introduction of 3D GDCs into our practice significantly improved the initial occlusion rate but did not affect the incidence of recanalization.
authors.affiliation: Department of Neuroradiology, University Hospital of Bern, Bern, Switzerland.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Mordasini
authors.forename: Gerhard
authors.initials: G
authors.lastname: Schroth
authors.forename: Raphael
authors.initials: R
authors.lastname: Guzman
authors.forename: Alain
authors.initials: A
authors.lastname: Barth
authors.forename: Rolf W
authors.initials: RW
authors.lastname: Seiler
authors.forename: Luca
authors.initials: L
authors.lastname: Remonda
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002533:Cerebral Angiography; D004621:Embolization, Therapeutic / Q000009:adverse effects / Q000295:instrumentation* / Q000401:mortality; D005260:Female; D005500:Follow-Up Studies; D023261:Glasgow Outcome Scale; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D019233:Retreatment; D012189:Retrospective Studies; D016896:Treatment Outcome