Serpiginous cholesteatoma mimicking a vascular channel

A 36-year-old male who had history of hearing loss since childhood presented with a chronically discharging right ear. HRCT temporal bones revealed non-dependent opacification in the epiand meso-tympanum with medially displaced head of malleus, erosion of incus and the tegmen tympani suspicious for an attic cholesteatoma. In addition, there was a serpiginous structure seen extending across the posterior aspect of the mastoid temporal bone which was thought to represent a trans-mastoid emissary vein. MRI subsequently performed showed both the lesions (in the middle ear cavity and the serpiginous structure in the mastoid) were hyperintense on Propeller DW (b value 1000 sec/mm) sequence suggesting 2 cholesteatomas. The serpiginous structure in the mastoid did not show post contrast enhancement thus excluding a vascular lesion. A canal wall down mastoidectomy was done which confirmed both the findings.