title: Aneurysm Recurrence Volumetry Is More Sensitive than Visual Evaluation of Aneurysm Recurrences.
abstract: OBJECTIVE
  Considerable inter-observer variability in the visual assessment of aneurysm recurrences limits its use as an outcome parameter evaluating new coil generations. The purpose of this study was to compare visual assessment of aneurysm recurrences and aneurysm recurrence volumetry with an example dataset of HydroSoft coils (HSC) versus bare platinum coils (BPC).
  
  
  METHODS
  For this retrospective study, 3-dimensional time-of-flight magnetic resonance angiography datasets acquired 6 and 12 months after endovascular therapy using BPC only or mainly HSC were analyzed. Aneurysm recurrence volumes were visually rated by two observersas well as quantified by subtraction of the datasets after intensity-based rigid registration.
  
  
  RESULTS
  A total of 297 aneurysms were analyzed (BPC: 169, HSC: 128). Recurrences were detected by aneurysm recurrence volumetry in 9 of 128 (7.0 %) treated with HSC and in 24 of 169 (14.2 %) treated with BPC (odds ratio: 2.39, 95 % confidence interval: 1.05-5.48; P = 0.039). Aneurysm recurrence volumetry revealed an excellent correlation between observers (Cronbach's alpha = 0.93). In contrast, no significant difference in aneurysm recurrence was found for visual assessment (3.9 % in HSC cases and 4.7 % in BPC cases). Recurrences were observed in aneurysms smaller than the sample median in 10 of 33 (30.3 %) by aneurysm recurrence volumetry and in 1 of 13 (7.7 %) by visual assessment.
  
  
  CONCLUSIONS
  Aneurysm recurrences were detected more frequently by aneurysm recurrence volumetry when compared with visual assessment. By using aneurysm recurrence volumetry, differences between treatment groups were detected with higher sensitivity and inter-observer validity probably because of the higher detection rate of recurrences in small aneurysms.
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany. m.schoenfeld@uke.de.
authors.forename: M H
authors.initials: MH
authors.lastname: Schönfeld
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
authors.forename: V
authors.initials: V
authors.lastname: Schlotfeldt
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
authors.forename: N D
authors.initials: ND
authors.lastname: Forkert
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Goebell
authors.affiliation: Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Groth
authors.affiliation: Department of Medical Biometry and Epidemiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Vettorazzi
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
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, 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
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 Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Fiehler
mesh_terms: D002983:Clinical Competence / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods* / Q000706:statistics & numerical data; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000628:therapy*; D007723:Korea / Q000453:epidemiology; D018810:Magnetic Resonance Angiography / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D015588:Observer Variation; D010363:Pattern Recognition, Automated / Q000379:methods* / Q000706:statistics & numerical data; D015995:Prevalence; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D015607:Stents / Q000706:statistics & numerical data*; D016896:Treatment Outcome
keywords: 3D imaging; Coiling; Intracranial aneurysms; MR angiography; Recurrence