Fusion of computed tomography and diffusionweighted magnetic resonance images for detection of primary, residual and recurrent cholesteatoma of the middle ear

Abstract

Background: At present, computed tomography (CT) is recognized as method for primary diagnosis of middle ear disorders. More accurate diagnosis of cholesteatoma is based on a sequence of non-echo planar diffusion-weighted magnetic resonance imaging. The choice of the type of surgery depends on cholesteatoma size and location. Aim: To assess the possibility of fusion of CT and magnetic resonance images (MRI) to determine the precise location of the middle ear cholesteatoma. Materials and methods: The CT and diffusion-weighted (DW) images of 24 patients with chronic suppurative otitis media, including 12 with newly diagnosed and 12 with relapsing cholesteatoma were fused. The patients underwent the standard CT and MRI, including DW-MRI. CT and DW-MRI images were fused with determination of exact size and location of cholesteatoma in the middle ear cavity. Results: The exact location and size of the cholesteatoma were identified. The study results were compared with intraoperative data. The use of fused CT and DW images had the sensitivity in determination of cholesteatoma location and size of 96%, specificity of 100%, positive predictive value of 100%, and negative of 96%, which all were higher than the corresponding values for CT and MRI assessments. Conclusion: Fusion of CT and DW-MRI allows for determination of the precise localization of cholesteatoma, partial exclusion of false-positive results correlate and for comparison of the lesion with important bone landmarks. The method may be useful for the surgeon both in planning of primary surgery, as well as for repeated revision of the postoperative cavity.

Keywords

• diffusion-weighted imaging
• magnetic resonance imaging
• cholesteatoma
• computed tomography
• fusion