The unenhanced CT scan can suggest whether a lesion is cystic or solid and whether there are calcifications, hemorrhage, edema, and hydrocephalus. After intravenous contrast, enhancement of the tumor occurs because of a disruption of the blood-brain barrier. MRI s with gadolinium enhancement is a sensitive technique for the diagnosis of CNS tumors. MRI scans are potentially superior to CT scans in the detection and definition of low-grade glial tumors and of lesions at the vertex, within the posterior fossa, near the wall of the middle fossa, and at the base of the skull. MRI myelography with gadolinium enhancement is the best method for detecting spinal cord tumors or delineating leptomeningeal tumor invasion.
Tumor markers are also useful in selected malignant conditions.
Treatment is beyond the scope of this bulletin, but should also be reviewed.