title: Optical imaging with a high-resolution microendoscope to identify cholesteatoma of the middle ear.
abstract: OBJECTIVE
  High-resolution optical imaging is an imaging modality that allows visualization of structural changes in epithelial tissue in real time. Our prior studies using contrast-enhanced microendoscopy to image squamous cell carcinoma in the head and neck demonstrated that the contrast agent, proflavine, has high affinity for keratinized tissue. Thus, high-resolution microendoscopy with proflavine provides a potential mechanism to identify ectopic keratin production, such as that associated with cholesteatoma formation, and distinguish between uninvolved mucosa and residual keratin at the time of surgery.
  
  
  METHODS
  Ex vivo imaging of histopathologically confirmed samples of cholesteatoma and uninvolved middle ear epithelium.
  
  
  METHODS
  Seven separate specimens collected from patients who underwent surgical treatment for cholesteatoma were imaged ex vivo with the fiberoptic endoscope after surface staining with proflavine. Following imaging, the specimens were submitted for hematoxylin and eosin staining to allow histopathological correlation.
  
  
  RESULTS
  Cholesteatoma and surrounding middle ear epithelium have distinct imaging characteristics. Keratin-bearing areas of cholesteatoma lack nuclei and appear as confluent hyperfluorescence, whereas nuclei are easily visualized in specimens containing normal middle ear epithelium. Hyperfluorescence and loss of cellular detail is the imaging hallmark of keratin, allowing for discrimination of cholesteatoma from normal middle ear epithelium.
  
  
  CONCLUSIONS
  This study demonstrates the feasibility of high-resolution optical imaging to discriminate cholesteatoma from uninvolved middle ear mucosa based on the unique staining properties of keratin. Use of real-time imaging may facilitate more complete extirpation of cholesteatoma by identifying areas of residual disease. Laryngoscope, 2012.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Mount Sinai School of Medicine, New York, New York 10029, USA.
authors.forename: Lauren L
authors.initials: LL
authors.lastname: Levy
authors.forename: Nancy
authors.initials: N
authors.lastname: Jiang
authors.forename: Eric
authors.initials: E
authors.lastname: Smouha
authors.forename: Rebecca
authors.initials: R
authors.lastname: Richards-Kortum
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Sikora
mesh_terms: D018424:Cholesteatoma, Middle Ear / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D004396:Coloring Agents; D004724:Endoscopy; D004848:Epithelium / Q000473:pathology; D006801:Humans; D007633:Keratins / Q000378:metabolism; D061848:Optical Imaging; D011370:Proflavine
chemical_list: D004396:Coloring Agents; D007633:Keratins; D011370:Proflavine