The radiographic findings of cerebello-pontine angle lesions

ABSTRACT

Thirty-five cerebello-pontine angle lesions were diagnosed with simple skull X-ray, CT, and angiography atSeoul National University Hospital from Sept. 1978 through Aug. 1982. The radiographic findings were analysed withemphasis on the differential points of CT among the major three cerebello-pontine angle tumors; acousticneurinoma, meningioma and epidermoid. The results are as follows; 1. Among the 35 cases of cerebello-pontine anglelesions, 19 cases were acoustic neurinoma. 4 cases miningioma, 4 cases epidermoid, 2 cases metastasis, 1 caseschoroid plexus papilloma, 1 case arteriovenous malformation, and 3 cases intra-axial posterior fossa tumors. 2.The characteristic radiographic findings of acoustic neurinoma were windening of internal auditory canal, petrousbone erosion, posterior extension of tumor at the level of internal autidory canal, hypo or isodense mass onpre-contrast CT with high enhancement after intravenous contrast infusion, and cystic change within the mass. 3.Meningioma shows anterior extenstion of the lesion at the level of internal auditory canal, broad base and obtuseangle sign of the lesion with petrous bone, hyperdense mass on precontrast CT. with highly homogeneous enhancementafter intravenous contrast infusion. 4. Epidermoid characteristically shows hypodense mass on precontrast CT withno change after intravenous contrast infusion. 5. The differential points of the major 3 cerebello-pontine tumorswere bone change, mass location, attenuation , degree of attachment to petrous bone, and cystic change.