Attic Cholesteatoma Radiology

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Attic cholesteatoma radiology.

This case is a histologically proven case of cholesteatoma. Although a cholesteatoma is histologically identical to an epidermoid or epidermal. Keywords temporal bone cholesteatoma middle ear external auditory canal introduction a cholesteatoma is a cystic mass filled with keratin and lined by stratified squamous epithelium. The external acoustic canal is a rare location for a cholesteatoma with an estimated incidence around 1 2 per 1 000 new otological patients.

The mass extends superiorly into the attic and appears to have eroded through the tegmentum as well as through the fallopian canal of the facial nerve and perhaps the lateral semicircular canal. It is the only entity that demonstrates high signal intensity on dwi. On the adc map a low signal should be visible in the same area confirming the presence of diffusion restriction. The overall incidence rate in one large study was 0 30 per year per 100 000 inhabitants 1.

For comparison the annual incidence of middle ear cholesteatoma is around 9 2 per 100 000. On the dwi images with b value 1000 s mm 2 a cholesteatoma becomes apparent as a hyperintense area. Diffusion weighted imaging is particularly useful when distinguishing a cholesteatoma from other middle ear masses. However the sequence is prone to artefact and care must be taken how the sequence is performed and interpreted 2.