High-resolution three-dimensional diffusion-weighted MRI/CT image data fusion for cholesteatoma surgical planning: a feasibility study

The aim of the study was to assess the feasibility of high-resolution three-dimensional diffusion-weighted images (HR3D-DWIs)/multi-detector row CT (MDCT) images' data fusion for surgical planning for cholesteatoma. A total of 12 patients (7 male and 5 female; age range 11-72 years; mean 38.1 years) with cholesteatoma underwent preoperative MRI using a 3.0-T clinical unit and an 8-channel array-head coil. For each subject, HR3D-DWIs were obtained using a turbo field-echo with diffusion-sensitized driven-equilibrium preparation with 1.5 mm iso-voxel dimension. These patients also underwent MDCT with a slice thickness of 0.5 mm. Fusion of the HR3D-DWIs and MDCT images was performed using an automated rigid registration and subsequent manual fine-tuning by a board-certified neuroradiologist on a workstation. Fused images were compared to CT and findings confirmed based on operation reports. On the fused images, the extent of the cholesteatoma, which was depicted as a conspicuous high-intensity lesion could be easily evaluated with background bony structures. In all patients, the location and extent of the cholesteatoma on the fused images corresponded well with the intraoperative findings. Image fusion between HR3D-DWIs and MDCT images is feasible, and provides valuable preoperative information for surgical planning to otorhinolaryngologists.