title: Evaluation of the internal auditory canal with virtual endoscopy.
abstract: OBJECTIVE
  Three-dimensional imaging can improve the understanding and comprehension of complex anatomy. Recent advances in software development allow the construction of a virtual endoscopic view of anatomic structures. This report applies virtual endoscopic capabilities to imaging of the internal auditory canal.
  
  
  METHODS
  We conducted a retrospective case review at a tertiary referral center of patients with abnormal internal auditory canal anatomy on computed tomography.
  
  
  METHODS
  Computed tomography images were obtained using conventional clinical algorithms involving multiple, 1-mm-thick slices through the temporal bone. Three-dimensional reconstructions were made using General Electric Advantage Windows Navigator software. The virtual endoscopic image-processing algorithm used selected image intensity threshold levels to visualize internal auditory canal anatomy from an endoscopic perspective.
  
  
  RESULTS
  Eleven cases of abnormalities of the internal auditory canal were retrospectively identified. Clinical applications using the virtual endoscopic images are presented. The virtual endoscopic images supported prior clinical decision making in 6 of the 11 cases evaluated.
  
  
  CONCLUSIONS
  This technique shows promise for the diagnosis, surgical planning, and teaching of temporal bone anatomy. Usefulness is dependent on acquisition parameters and clinical indications for examination.
authors.affiliation: Bobby R. Alford Department of Otolaryngology and Communicative Sciences, Baylor College of Medicine, Houston, Texas, USA. jvrabec@bcm.tmc.edu
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Vrabec
authors.forename: Russell D
authors.initials: RD
authors.lastname: Briggs
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Rodriguez
authors.forename: Raleigh F
authors.initials: RF
authors.lastname: Johnson
mesh_terms: D000465:Algorithms; D004427:Ear Diseases / Q000000981:diagnostic imaging*; D007758:Ear, Inner / Q000002:abnormalities* / Q000000981:diagnostic imaging*; D004724:Endoscopy / Q000379:methods / Q000592:standards; D005240:Feasibility Studies; D005357:Fibrous Dysplasia of Bone / Q000000981:diagnostic imaging; D050723:Fractures, Bone / Q000000981:diagnostic imaging; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods / Q000592:standards; D009464:Neuroma, Acoustic / Q000000981:diagnostic imaging; D010016:Osteoma / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D013701:Temporal Bone / Q000002:abnormalities* / Q000000981:diagnostic imaging* / Q000293:injuries; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000592:standards; D014584:User-Computer Interface