INTRAMEATAL TUMORS PRESENTING AS A HEARING DISTURBANCE - CASE-REPORTSOF MENINGIOMA AND LYMPHOMA

This paper presents two patients with chronic progressive hearing dist urbance. Each patient had an intrameatal tumour, part of which extende d to the cerebellopontine (CP) angle. In both cases, the patients were initially diagnosed with an acoustic neurinoma. A 63-year-old male ex perienced a hearing disturbance in the left ear for 1.5 years prior to visiting our hospital. Magnetic resonance (MR) imaging revealed a mas s which was surgically resected. The tumour originated from the intram eatal dura mater. Histologically, the tumour was a meningioma. Similar ly, a 53-year-old male presented with systemic lymphoma diagnosed 10 m onths earlier, and a hearing disturbance in the right ear that began 3 months prior to visiting our hospital. MR imaging prior to chemothera py revealed a mass which extended to the CP angle. Part of the tumour in the CP angle disappeared after chemotherapy, suggesting a secondary lymphoma. Another tumour appeared later in Meckel's cave on the left side; however, it decreased in size following repeated chemotherapy. T he present results indicate that differential diagnosis of intrameatal tumours and acoustic neurinomas may be difficult due to the small tum our size. Recent progress in neuroradiology may allow distinction of i ntrameatal rumours as a separate tumour classification. Our second pat ient is the sixth reported case of a CP angle lymphoma in the literatu re.