A peripherally enhancing lesion in the right lower pons, extending into the cerebellopontine angle abuts but does not appear to involve the right cerebellar hemisphere; the right vertebral artery passes anteriorly to it. There is a small amount of adjacent hypoattenuation in the pons, in keeping with oedema. There is localised mass effect with a small degree of effacement of the right pre medullary cistern secondary to the mass. Normal fourth ventricle calibre.