Vestibular schwannoma is the most common tumor presenting in the cerebello-pontine (CP) angle. While, we often find the other kinds of small CP angle tumors, such as meningioma, lipoma, hemangioma, because of the development of diagnostic tool such as MRI.
We underwent tumor removal for 527 cerebello-pontine angle tumors including 20 meningiomas, 10 facial neurinoma 10 epidermoids, 6 trigeminal schwannomas, 3 lipomas, 2 astorocytomas, 2 chordomas, 2 hypoglossal schwannoma, one choroid plexus papilloma, one hemangioma, one arachnoid cyst from 1975 to 1998.
Preoperative differential diagnosis based on MRI usually helps surgeons to formulate an appropriate treatment protocol. While, we sometimes fail in diagnosis with MRI, especially in small tumors. In this paper, we showed the two CP angle tumor cases which we failed in preoperative diagnosis in MRI. We also discussed about the diagnostic problems in MRI for these CP angle tumors.
We also realized that we have to cosider the difference in the principals between conventional MRI technique and our MRI technique (SPGR).
