Cerebellopontine Angle Lipoma

Abstract

In adults cerebellopontine angle lesions consist of 6-10% of all intracranial tumours. Acoustic neuroma, meningioma and epidermoid cysts are the most frequently encountered tumors of the cerebellopontine angle. In this paper we presented imaging findings of quiet rarely seen lipomas which represent 0.15% of all cerebellopontine angle lesions. Intracranial lipomas demonstrate characteristic signs on computed tomography and magnetic resonance imaging which establish the diagnosis. On computed tomograms lesions are homogen, well circumscribed, nonenhancing hypodense in fat density (-70 to -110HU), while on magnetic resonance imaging, lesions are hyperintense on T1-weighted images, and mostly iso-hypointense on T2-weighted images, nonenhancing, hypointense on T1-weighted fat suppression images. Lesions show chemical shift artefacts on T2-weighted images. Hyperintense lesions on T1-weighted images which represent dermoid, melanoma and cholesterol granulomas must be considered in the differential diagnosis.