Contribution of magnetic resonance imaging to the diagnosis of middle ear cholesteatoma: analysis of a series of 97 cases

Objectives: To evaluate the reliability of magnetic resonance imaging (MRI) for the diagnosis of middle ear cholesteatoma and to determine the contribution of each MRI sequence.

Patients and methods: A series of 97 cases was reviewed, corresponding to 89 patients (43 women, 46 men). Each patient was assessed by the following MRI protocol: T1-weighted, T2-weighted, early contrast-enhanced T1-weighted, delayed contrast-enhanced T1-weighted, and diffusion-weighted sequences. All patients were operated, for the first time in 16 cases and for second-look surgery in 81 cases. Radiological findings were compared to surgical and histological findings. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for each sequence.

Results: Seventy-four cholesteatomas were diagnosed at surgery. These lesions had a mean diameter of 8.29±5.46mm. The smallest cholesteatoma in this series was 2mm in diameter. Diffusion-weighted and delayed contrast-enhanced T1-weighted sequences had a sensitivity of 84.9% and 90.4%, a specificity of 87.5% and 75%, a positive predictive value of 95.4% and 91.7%, and a negative predictive value of 65.6% and 72%, respectively. T1-weighted, T2-weighted, and early contrast-enhanced T1-weighted sequences had a low specificity.

Conclusions: MRI is a reliable imaging modality for the diagnosis of middle ear cholesteatoma. Diffusion-weighted and delayed contrast-enhanced T1-weighted sequences were discriminant. In the context of postoperative follow-up of cholesteatoma, these sequences allow better selection of cases requiring second-look surgery.