title: Use of a new soft and long coil reduces the number of coils to embolize a small aneurysm.
abstract: BACKGROUND
  In embolizing a cerebral aneurysm, achievement of a high-volume embolization ratio (VER: volume of inserted coils / aneurysm volume) is important because it may prevent coil compaction and recanalization. The goal of the study is to examine whether use of softer and longer coils gives an adequate VER with fewer coils, particularly for small aneurysms.
  
  
  METHODS
  Aneurysm volumes, VERs, and numbers of inserted coils were investigated in 23 cases of small aneurysms embolized using Infini coils, a long soft coil with a primary diameter of 0.010 inches (Infini group). An aneurysm volume- and VER-matched control (non-Infini) group of 59 cases was selected from patients treated at our facility. Data were also compared between subgroups of patients (n = 18 and n = 34 in the Infini and non-Infini groups, respectively) who were not treated with thicker coils with primary diameters of 0.0135-0.015 inches (18-type coils), since these coils affect the number of coils by increasing VER rapidly.
  
  
  RESULTS
  Average aneurysm volumes and VERs did not differ significantly between the Infini and non-Infini groups. Significantly fewer coils were used per 0.1 ml aneurysm volume in the Infini group (4.08 coils in average) compared with the non-Infini group (5.67) (p < 0.001). In the non-18-type subgroups, the number of coils used remained significantly smaller in the Infini group (4.49) compared with the non-Infini group (6.72), (p < 0.001).
  
  
  CONCLUSIONS
  To achieve VER ≥20%, use of Infini coils significantly decreased the number of coils required per unit volume of a small aneurysm.
authors.affiliation: Department of Neurosurgery, Fujita Health University; Toyoake City, Aichi, Japan asadato@fujita-hu.ac.jp.
authors.forename: Akiyo
authors.initials: A
authors.lastname: Sadato
authors.affiliation: Department of Neurosurgery, Fujita Health University; Toyoake City, Aichi, Japan.
authors.forename: Motoharu
authors.initials: M
authors.lastname: Hayakawa
authors.affiliation: Department of Neurosurgery, Fujita Health University; Toyoake City, Aichi, Japan.
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Adachi
authors.affiliation: Department of Neurosurgery, Fujita Health University; Toyoake City, Aichi, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Kato
authors.affiliation: Department of Neurosurgery, Fujita Health University; Toyoake City, Aichi, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Hirose
mesh_terms: D000328:Adult; D000368:Aged; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation; D002405:Catheterization, Central Venous; D004621:Embolization, Therapeutic / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000628:therapy*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D010984:Platinum; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D010984:Platinum
keywords: Aneurysm; long coil