title: Verification of computed tomographic estimates of cochlear implant array position: a micro-CT and histologic analysis.
abstract: OBJECTIVE
  To determine the efficacy of clinical computed tomographic (CT) imaging to verify postoperative electrode array placement in cochlear implant (CI) patients.
  
  
  METHODS
  Nine fresh cadaver heads underwent clinical CT scanning, followed by bilateral CI insertion and postoperative clinical CT scanning. Temporal bones were removed, trimmed, and scanned using micro-CT. Specimens were then dehydrated, embedded in either methyl methacrylate or LR White resin, and sectioned with a diamond wafering saw. Histology sections were examined by 3 blinded observers to determine the position of individual electrodes relative to soft tissue structures within the cochlea. Electrodes were judged to be within the scala tympani, scala vestibuli, or in an intermediate position between scalae.
  
  
  RESULTS
  The position of the array could be estimated accurately from clinical CT scans in all specimens using micro-CT and histology as a criterion standard. Verification using micro-CT yielded 97% agreement, and histologic analysis revealed 95% agreement with clinical CT results.
  
  
  CONCLUSIONS
  A composite, 3-dimensional image derived from a patient's preoperative and postoperative CT images using a clinical scanner accurately estimates the position of the electrode array as determined by micro-CT imaging and histologic analyses. Information obtained using the CT method provides valuable insight into numerous variables of interest to patient performance such as surgical technique, array design, and processor programming and troubleshooting.
authors: Department of Program in Audiology and Communication Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Jessica
authors: J
authors: Teymouri
authors: Timothy E
authors: TE
authors: Hullar
authors: Timothy A
authors: TA
authors: Holden
authors: Richard A
authors: RA
authors: Chole
mesh_terms: D003051:Cochlea / Q000000981:diagnostic imaging* / Q000601:surgery; D019929:Cochlear Implantation / Q000379:methods*; D003054:Cochlear Implants; D006801:Humans; D011859:Radiography; D013701:Temporal Bone / Q000000981:diagnostic imaging* / Q000601:surgery