Evaluation of diffusion weighted MRI sequence as a predictor of middle ear cleft cholesteatoma : imaging, operative and histopathological study

الملخص EN

Objectives : Non-echoplanar imaging (Non-EPI) MRI has been recently introduced to improve the detection of small sized cholesteatoma and decrease different artifacts occurring in the echo-planar diffusion weighted image (EPI DWI) technique.

It is a time saving procedure in comparison to the delayed postcontrast imaging.

We prospectively assessed the diagnostic accuracy of Non-EPI-DW sequences in the detection of middle ear cleft cholesteatoma.

Material and methods : Forty patients suspected to have cholesteatoma were collected from the ENT outpatient clinic of a tertiary referral center.

Twenty patients underwent primary mastoid surgery, ten patients scheduled for revision mastoid surgery, while the remaining patients underwent second look operation after one year of their first surgery.

All patients underwent Non-EPI-DW sequences prior to their planned surgery.

Diagnosis of cholesteatoma was based on evidence of a hyperintense lesion on diffusion-weighted images that were correlated with the surgical findings and histopathological examination, which was used as the gold standard for diagnostic confirmation.

Sensitivity, specificity and predictive values of MRI were estimated.

Results : Diffusion weighted imaging accurately predicted the presence of cholesteatoma in 88.2% of cases, and it correctly excluded it in 100% of cases.

Sensitivity, specificity, positive and negative predictive values were 88.24%, 100%, 100% and 60%, respectively.

Non-echo-planar DWI has been shown to have a high sensitivity and specificity for detecting recurrent cholesteatoma.

Conclusions : Non-echoplanar DWI is an effective technique in cholesteatoma diagnosis.

It is capable of detecting lesions larger than 2 mm.