<unk> s have been divided into three types based on their patterns of growth. Histological factors that increase the grade include a high number of mitotic figures, necrosis and local invasion. Treatment of<unk> s often depends on the location and size of the tumor. Gamma knife radiation and microscopic surgery are common options. Their encapsulated, slow growth makes<unk> s good targets for radiosurgery. In one series, less than one-third of clinoidal<unk> s could be completely resected without unacceptable risk of damaging of blood vessels (especially the carotid artery) or cranial nerves, risks that are lower with radiosurgery. If surgery is done and the entire tumor cannot be removed, then external beam radiation helps reduce recurrence of the growth. In fact, surgery followed by radiation at recurrence provided excellent tumor control in cases where gross-total resection cannot be achieved. Most all<unk> s grow very slowly and almost never metastasize to other parts of the body. In part because of its slow growth, if a tumor is asymptomatic and found only by imaging, the best course is often observation with serial clinical exams and imaging. Possible indications for intervention would be a rapid increase in growth or involvement of cranial nerves. Untreated, one small series showed survival rates ranging from five to over twenty years, though most suffered unilateral blindness as well as paresis of extraocular movements.
Sphenoid wing meningioma
Medulloblastoma
Pineoblastoma
Hemangioblastoma
Subependymoma
Choroid plexus papilloma
Sialoblastoma
Vestibular schwannoma