title: Do Contrast-Fill Patterns Immediately After Coil Embolization of Small Saccular Aneurysms Impact Long-Term Results?
abstract: OBJECTIVE
  It is generally accepted that filling of a saccular aneurysm with contrast immediately after coil embolization predisposes to later recanalization. However, not all such scenarios evolve similarly over time. We investigated outcomes of small (≤ 7 mm) aneurysms with contrast-filled sacs immediately after coil embolization, evaluating the impact of pattern and degree of filling on subsequent recanalization.
  
  
  METHODS
  Between January, 2008 and December, 2010, 186 small (≤ 7 mm) saccular aneurysms that retained contrast after coil embolization accrued for this study. Lesions were categorized by pattern (eccentric vs. concentric) and degree of filling on working projections. Clinical and morphologic factors were also analyzed to assess impact on subsequent recanalization. Morphologic outcomes at 6 months or more were assessed.
  
  
  RESULTS
  In 93.5 % (174/186) of aneurysms with visible contrast retention, complete occlusion was evident on follow-up imaging studies at 6 months. Multiple logistic regression analysis indicated that eccentric (vs. concentric) contrast filling carried greater risk of subsequent recanalization (p = 0.020). Stent placement and progressive occlusion were also linked, falling short of statistical significance (p = 0.089). Of 166 progressively occluded aneurysms followed for more than 12 months (mean, 30.8 ± 7.3 months), 158 (95.2 %) exhibited stable occlusion.
  
  
  CONCLUSIONS
  Small (≤ 7 mm) aneurysms that retain contrast immediately after coil embolization are more likely to become completely occluded over time through progressive thrombosis. However, an eccentric fill pattern may predispose to recanalization.
authors.affiliation: Department of Neurosurgery, Hallym University College of Medicine, Chuncheon, Korea.
authors.forename: J P
authors.initials: JP
authors.lastname: Jeon
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu Seoul, Seoul 110-744, Seoul, Korea. aronnn@naver.com.
authors.forename: Y D
authors.initials: YD
authors.lastname: Cho
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu Seoul, Seoul 110-744, Seoul, Korea.
authors.forename: J K
authors.initials: JK
authors.lastname: Rhim
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu Seoul, Seoul 110-744, Seoul, Korea.
authors.forename: D H
authors.initials: DH
authors.lastname: Yoo
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: H-S
authors.initials: HS
authors.lastname: Kang
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: J E
authors.initials: JE
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: W S
authors.initials: WS
authors.lastname: Cho
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, 101 Daehak-ro, Jongno-gu Seoul, Seoul 110-744, Seoul, Korea.|Department of Neurosurgery, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: M H
authors.initials: MH
authors.lastname: Han
mesh_terms: D002533:Cerebral Angiography / Q000379:methods*; D002536:Cerebral Arteries / Q000000981:diagnostic imaging*; D003287:Contrast Media; D004621:Embolization, Therapeutic / Q000295:instrumentation / Q000379:methods*; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000628:therapy*; D008137:Longitudinal Studies; D008297:Male; D061185:Mechanical Thrombolysis / Q000295:instrumentation / Q000379:methods*; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media
keywords: Aneurysm; Coil; Embolization; Incomplete occlusion; Recanalization