title: High-resolution computed tomography-based length assessments of the cochlea--an accuracy evaluation.
abstract: CONCLUSIONS
  The length of the cochlea can be determined with good precision using a 3D-curved multiplanar reconstruction analysis technique and linear reconstruction of the cochlea. The method is not time-consuming and can be applied during clinical routine.
  
  
  OBJECTIVE
  A preoperative prediction of the best cochlear implant electrode length can help reduce the risk of intraoperative cochlear trauma in patients who need to retain residual acoustic hearing for electric-acoustic stimulation or in patients with anatomical anomalies or malformations. The goal of this study was to evaluate the accuracy and reliability of length measurement of the cochlea after linear reconstruction using 3D-curved multiplanar reconstrucion analysis of high resolution computed tomography (CT) scans.
  
  
  METHODS
  Human cadaveric temporal bone specimens underwent cochlear implantation using custom-made electrodes with two radiopaque markers of a defined length before CTscans were made. Length measurement was performed by four readers and the results were compared to the true value. Inter-reader reliability was calculated. The time needed for analysis was recorded.
  
  
  RESULTS
  The mean time needed for analysis of one specimen's radiologic data was 6.1 (± 3.4) min. The mean deviation of the length measurement from the true value was 0.8 (± 0.7) mm. Inter-reader reliability was excellent (0.76, p = 0.006).
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, University of Munich.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Kisser
authors.forename: Birgit
authors.initials: B
authors.lastname: Ertl-Wagner
authors.forename: John Martin
authors.initials: JM
authors.lastname: Hempel
authors.forename: Joachim
authors.initials: J
authors.lastname: Müller
authors.forename: Melvin
authors.initials: M
authors.lastname: D'Anastasi
authors.forename: Florain
authors.initials: F
authors.lastname: Schrötzlmair
authors.forename: Christine
authors.initials: C
authors.lastname: Adderson-Kisser
authors.forename: Ruediger P
authors.initials: RP
authors.lastname: Laubender
authors.forename: Klaus
authors.initials: K
authors.lastname: Stelter
authors.forename: Christian
authors.initials: C
authors.lastname: Braun
authors.forename: Andreas
authors.initials: A
authors.lastname: Pomschar
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D003051:Cochlea / Q000033:anatomy & histology* / Q000000981:diagnostic imaging* / Q000601:surgery; D019929:Cochlear Implantation / Q000379:methods; D003054:Cochlear Implants; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013701:Temporal Bone / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Multiplanar reconstruction; cochlear implant; temporal bone