Learning Objectives: 1) To identify the rate of false positives and false negatives in our patients by correlating the radiological findings of D2-weighted MRI with intra-operative findings in patients with primary and recurrent cholesteatoma. 2) To determine the value of D2-weighted MRI in preventing the need for second-look surgery. 3) To determine whether a specific diameter of lesion observed on MRI can be established in order to predict the clinical significance of recurrent cholesteatomas.

Introduction: There has been increasing evidence that demonstrates the accuracy of non-echo-planar diffusion-weighted magnetic resonance imaging in the identification of cholesteatoma. This retrospective study aims to determine if the sensitivity and specificity of D2-weighted MRI used to evaluate the presence and recurrence of cholesteatoma, in the North of Scotland, is coherent with current published literature.

Method: Retrospective collection of data between January 2012 to December 2015 was conducted on patients that have undergone cholesteatoma surgery using operation codes and the review of theatre diaries. Electronic records of D2-weighted MRI findings and operative notes were reviewed and compared for comprehensive anaylsis. Results were then quantified in order to identify measureable outcomes (eg specificity, sensitivity).

Results: 41 of 235 patients whom had gone under tympano-mastoid surgery were confirmed to have received D2-weighted MRI. The results of this study are predicted to be concurrent with recent published data with a similar degree of sensitivity and specificity.

Conclusion: The high degree of accuracy in D2-weighted MRI observed will continue to decrease the need for second-look surgery in the North of Scotland. Data accumulated will provide additional evidence in the reliability of D2-weighted MRI to predict the clinical significance of recurrent cholesteatomas.