It predominately affects young and middle aged patients of Northern European extraction. The diagnosis is usually made on clinical findings, with intermittent symptoms implicating specific sites of CNS involvement separated by time and place. The initial relapsing and remitting course frequently shifts into a chronic progressive course in later years. Several additional lesions were seen on other slices. The lesions are usually small and homogeneous.
Active lesions can enhance with contrast.
These structures are found in the bones at the base of the brain. MRI is far superior to CT in evaluating these lesions since CT is severely limited by artifact from the dense bones at the skull base and restriction to the transverse plane. The normal right IAC is seen on the axial images. The tumors are usually round or oval shaped, can be small or large, can be limited to the internal auditory canal or extend into the space next to the canal, and demonstrate diffuse enhancement with contrast. All Rights Reserved.