Primary choroid plexus papilloma of the cerebellopontine angle: magnetic resonance imaging, computed tomographic and angiographic appearances.

The computed tomographic, angiographic and magnetic resonance imaging (MRI) appearances of a benign primary choroid plexus papilloma of the cerebellopontine angle are reported. Although benign, this tumour showed local invasion of the petrous temporal bone and mastoid air cells. The differential diagnosis of cerebellopontine angle lesions is discussed. Papilloma is suggested by the presence of a vascular, calcified, enhancing extra-axial mass in or around the cerebellopontine angle. MRI may show evidence of high vascularity and internal haemorrhage. Differentiation from other cerebellopontine tumours, most particularly meningioma, may not be possible on radiological features.