The Value of Diffusion-Weighted MRI in the Long-term follow-up After Subtotal Petrosectomy for Extensive Cholesteatoma and Chronic Suppurative Otitis Media

Objective: To report the long-term follow-up with diffusion-weighted magnetic resonance imaging (DW MRI) after subtotal petrosectomy (SP) with blind sac closure of the external auditory canal for extensive cholesteatoma and chronic suppurative otitis media. Study Design: Retrospective clinical record study. Setting: Tertiary referral center. Patients: Thirty-one patients (31 ears) with extensive cholesteatoma and 17 patients (19 ears) with chronic suppurative otitis media without cholesteatoma who underwent SP between July 1995 and December 2015. Interventions: All 48 patients were followed clinically and with DW MRI to rule out residual cholesteatoma. Main Outcome Measure: Residual cholesteatoma, indicated by a marked hyperintensity on non-echoplanar (non-EP) DW MRI. Results: In the cholesteatoma group the mean interval between surgery and the latest DW MRI was 3.9 years. Seven patients presented with a residual cholesteatoma pearl. The mean interval between surgery and detection of residual disease was 3.7 years. In the chronic suppurative otitis media group the mean interval between surgery and the latest DW MRI was 5.3 years. Residual cholesteatoma was found in three patients. Mean interval between surgery and the detection of disease was 4.5 years. Conclusions: This study shows the importance of DW MRI in the follow-up after SP for cholesteatoma and chronic suppurative otitis media. A little higher residual cholesteatoma rate was found compared with earlier studies, where patients were followed only clinically. One may wonder whether reintervention is always needed or whether in selected cases with small pearls, one may still observe these by a watchful waiting policy with DW MRI.