title: Comparison of Middle Ear Visualization With Endoscopy and Microscopy.
abstract: BACKGROUND
  The primary goal of chronic ear surgery is the creation of a safe, clean dry ear. For cholesteatomas, complete removal of disease is dependent on visualization. Conventional microscopy is adequate for most dissection, but various subregions of the middle ear are better visualized with endoscopy.
  
  
  OBJECTIVE
  The purpose of the present study was to quantitatively assess the improved visualization that endoscopes afford as compared with operating microscopes.
  
  
  METHODS
  Microscopic and endoscopic views were simulated using a three-dimensional model developed from temporal bone scans. Surface renderings of the ear canal and middle ear subsegments were defined and the percentage of visualization of each middle ear subsegment, both with and without ossicles, was then determined for the microscope as well as for 0-, 30-, and 45-degree endoscopes. Using this information, we analyzed which mode of visualization is best suited for dissection within a particular anatomical region.
  
  
  RESULTS
  Using a 0-degree scope provides significantly more visualization of every subregion, except the antrum, compared with a microscope. In addition, angled scopes permit visualizing significantly more surface area of every subregion of the middle ear than straight scopes or microscopes.
  
  
  CONCLUSIONS
  Endoscopes offer advantages for cholesteatoma dissection in difficult-to-visualize areas including the sinus tympani and epitympanum.
authors.affiliation: *Department of Otolaryngology-Head and Neck Surgery †Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville, Tennessee.
authors.forename: Marc L
authors.initials: ML
authors.lastname: Bennett
authors.forename: Dongqing
authors.initials: D
authors.lastname: Zhang
authors.forename: Robert F
authors.initials: RF
authors.lastname: Labadie
authors.forename: Jack H
authors.initials: JH
authors.lastname: Noble
mesh_terms: D018424:Cholesteatoma, Middle Ear / Q000601:surgery; D004424:Ear Canal / Q000601:surgery; D004432:Ear, Middle / Q000601:surgery; D004724:Endoscopy / Q000379:methods*; D006801:Humans; D008853:Microscopy / Q000379:methods*; D013506:Otologic Surgical Procedures / Q000379:methods*