Chordomas can be classified into three subgroups. The most common are the conventional chordomas, which are distinguished by the absence of mesenchymal elements such as cartilage. On histologic examination, lobules…

Histologically, vestibular schwannomas appear quite similar to peripheral schwannomas. On a microscopic level, there are zones of dense and sparse cellularity, identified as Antoni A and B areas, respectively. They…

Non–germ cell tumors include pineal parenchymal tumors, glial tumors, and metastasis from systemic tumors. Pineal parenchymal tumors are traditionally classified as the lower-grade pineocytoma and the malignant pineoblastoma. Pineocytomas occur…

The retromastoid suboccipital approach can be used for any size tumor with or without attempts to preserve hearing. This technique allows the tumor and the important structures medial and lateral…

With surgery, about 87% of patients have reported improvement in preoperative visual deficits, and many patients have reported improvement in preoperative endocrine deficits. Recurrence can occur but is rare in…

The pituitary gland is located in the sella turcica in the body of the sphenoid bone. The tuberculum sellae forms the anterior border of the sella turcica, and the dorsum…

Craniopharyngiomas are typically slow growing with slow onset of symptoms. Visual deficits are a common complaint due to direct pressure of the tumor on the optic chiasm. Hormonal abnormalities can…

Because the majority of meningiomas are very slowly growing, the brain has time to adapt to the enlarging mass. Thus tumors in the frontal or occipital lobe can become quite…

The WHO classification schema is based on histopathologic morphology and correlates with prognosis. WHO grade I lesions are considered benign and by far comprise the majority of meningiomas. These are…

Three mechanisms have been described for the development of metastases. For parenchymal lesions, the most common is hematogenous spread. Metastatic lesions are usually found at the junction between gray and…