Aspects on the treatment of gliomas of the anterior visual pathway.

Partial excision of the glioma of the anterior visual pathway seemed to have no effect on the vision in 7 patients and had a negative effect in 2. These results support the opinion that no excision should be made in such tumours. However, the course of the disease in one exceptional patient raises doubts about the general validity of this rule. In this case the postulated chiasmal glioma proved to be an exophytic glioma arising in one intracranial optic nerve and compressing the other. Excision of the exophytic portion caused rapid and considerable improvement of vision in both eyes. Direct visualization by craniotomy was needed to separate this mode of growth from the common intrinsic growth of such tumours.