[Neuroradiological evaluation of benign extramedullary tumors in the high cervical region and at the foramen magnum].

Twelve cases of benign extramedullary tumors in the high cervical region and at the foramen magnum were experienced during past five years among eighty all spinal and paraspinal tumors. The diagnosis of masses in this region is very difficult because of the variety of clinical course, symptoms and neurological findings as pointed out by many reporters. Also in our cases, 70% of the patients complained of the deteriorated motor weakness of the upper or lower extremities on admission, though they had noticed the onset of slight neck or occipital pain a few years ago. Neurological examination on admission clearly showed the symptom of myelopathy except in two cases with a tumor at the foramen magnum and C1 level. The percentage of positive findings of plain X-rays was 50%, that of metrizamide myelography was 92% and that of IV. e. CT and met. e. CT was 100%. NMR-CT was performed in 2 cases, and in one of them it was useful in confirming the tumor configuration and extension. Five interesting cases were described mainly from the neuroradiological aspects. Finally the differentiation between meningioma and neurinoma was discussed from the aspects of myelogram, CT and NMR-CT. As already pointed out, it is most important not to forget the existence of tumors in this region when one comes across the confused symptoms, afterwards not to overlook the slight positive neurological and neuroradiological findings.