Computed tomography and magnetic resonance fusion imaging in cholesteatoma preoperative assessment

The purpose of this study is to describe a method for developing fusion imaging for the preoperative evaluation of cholesteatoma. In 33 patients diagnosed with cholesteatoma, a high-resolution temporal bone computed tomography (CT) scan without intravenous contrast and propeller diffusion-weighted magnetic resonance imaging (MRI) were performed. Both studies were then sent to the BrainLAB work station, where the images were fused to obtain a morphological and color map. Intraoperative findings coincided with fusion CT–MRI imaging in all but two patients. In addition, one false positive and one false negative case were observed. CT and diffusion-weighted MRI are complementary techniques that should be employed to assess a cholesteatoma prior to surgery in many cases. Hence, to combine the advantages of each technique, we developed a fusion image technique similar to those that are routinely employed for radiotherapy planning and positron emission tomography–CT imaging. Fusion images can prove useful in selected cases.