title: Safety and effectiveness of large volume coils in the treatment of small aneurysms.
abstract: OBJECTIVE
  Large volume soft design coils facilitate quicker aneurysm filling and high packing density. Our purpose was to analyze the feasibility, safety, and effectiveness of the Penumbra Coil 400 (PC400) system in the treatment of small aneurysms.
  
  
  METHODS
  A retrospective analysis of prospective data collected at three different centers was performed on consecutive aneurysms <10 mm treated with the PC400 system. A total of 92 aneurysms were included in the study. Feasibility, procedure safety, angiographic and clinical results, and follow-up results were evaluated.
  
  
  RESULTS
  Mean aneurysm size was 5.8±2.0 mm. An average of 2.5±1.3 coils with a mean length of 18±16 cm per aneurysm was used, resulting in a mean packing density of 45.6±14.4%. The thromboembolic event rate was 3.3% and no procedural aneurysm rupture was observed. Immediate adequate occlusion was achieved in 66% of aneurysms. During a mean follow-up period of 7.4 months the number of adequate occlusions increased to 91%.
  
  
  CONCLUSIONS
  Large volume PC 400 coils are safe and effective in the treatment of small aneurysms with a low thromboembolic complication rate and no hemorrhagic events. High packing densities are achieved with a low average number of coils used per aneurysm treated. The aneurysms demonstrated progressive occlusion over time, which probably suggests stability in the long term.
authors.affiliation: Service of Diagnostic and Interventional Neuroradiology, Geneva University Hospitals, Geneva, Switzerland.|Interventional Work Research, CABMM, University of Zurich, Zurich, Switzerland.
authors.forename: Zsolt
authors.initials: Z
authors.lastname: Kulcsár
authors.affiliation: Interventional Work Research, CABMM, University of Zurich, Zurich, Switzerland.|Department of Neuroradiology, Swiss Neuro Institute, Klinik Hirslanden, Zurich, Switzerland.|Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital of Essen, Essen, Germany.
authors.forename: Isabel
authors.initials: I
authors.lastname: Wanke
authors.affiliation: Interventional Work Research, CABMM, University of Zurich, Zurich, Switzerland.|Department of Neuroradiology, Swiss Neuro Institute, Klinik Hirslanden, Zurich, Switzerland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Rüfenacht
authors.affiliation: Department of Neuroradiology, Swiss Neuro Institute, Klinik Hirslanden, Zurich, Switzerland.
authors.forename: Stephan G
authors.identifier: http://orcid.org/0000-0002-0003-3609
authors.initials: SG
authors.lastname: Wetzel
authors.affiliation: Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital of Essen, Essen, Germany.
authors.forename: Sophia
authors.initials: S
authors.lastname: Göricke
authors.affiliation: Department of Neuroradiology, Swiss Neuro Institute, Klinik Hirslanden, Zurich, Switzerland.
authors.forename: Kiriaki
authors.initials: K
authors.lastname: Kolia
authors.affiliation: Department of Radiology, Erlanger Health System, Chattanooga, Tennessee, USA.
authors.forename: Steven
authors.initials: S
authors.lastname: Quarfordt
authors.affiliation: Department of Radiology, Erlanger Health System, Chattanooga, Tennessee, USA.
authors.forename: Justin
authors.initials: J
authors.lastname: Calvert
authors.affiliation: Department of Radiology, Erlanger Health System, Chattanooga, Tennessee, USA.
authors.forename: Harris
authors.initials: H
authors.lastname: Hawk
authors.affiliation: Department of Radiology, Erlanger Health System, Chattanooga, Tennessee, USA.|Department of Radiology, University of Tennessee, College of Medicine Chattanooga, Tennessee, USA.
authors.forename: Blaise
authors.initials: B
authors.lastname: Baxter
keywords: Aneurysm; Coil; Hemorrhage; Subarachnoid