The role of high resolution C.T. scan Of the temporal bone in evaluating Patients with cholesteatomas

Abstract

This study was conducted on 49 patients (29 males and 20 females) from various age groups, presenting with various symptoms and signs of otologic disorder over a period of 24 months at Ain Shams University Hospitals and Ain Shams Specialized Hospital.

Beside history and clinical examination high resolution computed tomography on the temporal bone was done for 47 patients, two of them underwent additional MRl study while MRl was done for 2 patients without CT scan.

This study was done on patients with surgically proven to have cholesteatoma. Results show that while CT can detect abnormalities in the temporal bone, its ability to specify the diagnosis is limited.

We found that high resolution computed tomography of the temporal bone for patients with cholesteatoma not only detected the presence of the homogenous soft tissue density mass with focal areas of bone destruction but also detected the extent of the lesion, evaluated the ossicles regarding displacement and erosion, evaluated the facial canal and presence of complication like venous sinus thrombosis. It also played a role in detecting recurrence of the disease.

In our study CT detected the soft tissue density mass in all patients with good localization, although acquired cholesteatomas are classified into two types : Pars flaccida and Pars tensa, they are difficult to discriminate on CT scan especially when involvement is extensive. The CT detected bone destruction in 78% of cases and