Optical coherence tomography of cholesteatoma.

OBJECTIVES To image cholesteatoma using optical coherence tomography (OCT) and correlate the results with clinical findings and conventional observations obtained using binocular microscopy and histology. OCT is a high-resolution optical imaging modality that generates cross-sectional images of turbid media, such as tissue with resolution approaching that of light microscopy. OCT relies on intrinsic differences in tissue optical properties for image contrast. STUDY DESIGN In vivo prospective clinical study. SETTING University Medical Center. PATIENTS Patients with cholesteatoma undergoing otologic surgery. INTERVENTION Using a commercial OCT imaging system, we obtained cross-sectional images (resolution, approximately 10 microm; depth penetration, approximately 1 mm) of cholesteatomas. MAIN OUTCOME MEASURES Images are obtained by raster scanning a single mode fiber across the interior of the probe. The imaging probe is sterilized and inserted into the middle ear or mastoid under microscopic guidance, and still images of the middle ear or mastoid mucosa and cholesteatoma when present were obtained. RESULTS OCT images of cholesteatomas demonstrate differences in signal intensity, which are distinct from those of normal or inflamed middle ear/mastoid mucosa. Identification of keratin in cholesteatoma, even if very thin, distinguished it from inflamed mucosa. CONCLUSION This is the first study that systematically used OCT to image cholesteatoma during otologic surgery. Cholesteatomas can be distinguished from normal or inflamed adjacent mucosa.