title: Endovascular coil embolization of intracranial aneurysms: important factors related to rates and outcomes of incomplete occlusion.
abstract: OBJECTIVE
  The authors report on important factors that influenced clinical and angiographically demonstrated outcomes in patients treated using coil embolization.
  
  
  METHODS
  This study included 160 consecutive patients who underwent endovascular coil embolization for treatment of intracranial aneurysms. Univariate and multivariate logistic regression analyses were performed to assess factors that influenced the immediate posttreatment angiographic result. Cox regression analysis was used to establish factors related to the occurrence of negative events as well as a curve indicating the time to a negative event. Negative events were defined as aneurysm remnant increase, repeated treatment, rebleeding, or death during periprocedural hospitalization. Seventy-three percent of the patients treated in this study were independent or demonstrated no deficit (Glasgow Outcome Scale [GOS] Score 4 or 5) at a mean follow up of 18.2 months. The annual delayed rebleeding rate was 0.45%. Fifty percent of patients (65 of 131) suffered a negative event within 13 +/- 14 months (standard deviation). Statistically significant factors associated with the occurrence of negative events were rupture status (p = 0.0128) and immediate posttreatment angiographic result (p < 0.001). Overall clinical outcome assessed using the GOS was significantly related to the immediate posttreatment angiographic result (chi2 = 4.788, p = 0.029). The immediate post-treatment angiographic results were significantly influenced by catheter stability (p = 0.0012), aneurysm geometry (that is, simple or complex, p = 0.0053), and aneurysm neck diameter (p = 0.0205).
  
  
  CONCLUSIONS
  A good or excellent clinical outcome can be obtained in most patients treated using endovascular coil embolization of intracranial aneurysms. Note, however, that a significant number of patients treated using traditional platinum coils will harbor unstable aneurysm remnants or require repeated treatment.
authors.affiliation: Department of Clinical Neurological Sciences, University of Western Ontario, London Health Sciences Centre, London, Ontario, Canada. mkole1@hfhs.org
authors.forename: Max K
authors.initials: MK
authors.lastname: Kole
authors.forename: David M
authors.initials: DM
authors.lastname: Pelz
authors.forename: Paul
authors.initials: P
authors.lastname: Kalapos
authors.forename: Donald H
authors.initials: DH
authors.lastname: Lee
authors.forename: Irene B
authors.initials: IB
authors.lastname: Gulka
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Lownie
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography; D004621:Embolization, Therapeutic / Q000379:methods*; D005260:Female; D023261:Glasgow Outcome Scale; D006801:Humans; D002532:Intracranial Aneurysm / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012044:Regression Analysis; D016896:Treatment Outcome