A thorough evaluation is the first step in designing the best treatment plan. Your examination may include:

Computed Tomography   Magnetic Resonance Imaging MRI Spectroscopy MR perfusion Functional MRI Diffusion Tensor Imaging   Positron emission tomography (PET)

Your doctor may also ask for other tests, including:

Angiogram   Biopsy   Myelogram   Skull x-ray   Spinal tap

Spinal tap The doctor may remove a sample of cerebrospinal fluid (the fluid that fills the spaces in and around the brain and spinal cord). This procedure is performed with local anesthesia. The doctor uses a long, thin needle to remove fluid from the spinal column. A spinal tap takes about 30 minutes. The patient must lie flat for several hours afterward to keep from getting a headache. A laboratory checks the fluid for cancer cells or other signs of problems.