Imaging 
• Imaging has been conventionally done by CT for the brain and myelography for the spinal cord. Recently, 
  MRI imaging with gadolinium enhancement has been shown to be extremely sensitive, useful and simpler for  
  both the brain and spinal cord.
• Images of the entire brain and spinal cord should be done for tumors that may spread to the spinal cord 
  (medulloblastoma, ependymoma, intracranial germ cell tumors, pineal tumors, cerebral neuroblastoma—
  PNET).
• Bone scans are sometimes done in medulloblastoma because this tumor may spread outside the central nervous
  system, especially to bone.

Endoscopy and Biopsy 
• Tumors of the brain stem, the medulla and the pons (brain stem glioma) may be biopsied. The procedure is 
  risky. They cannot be removed surgically (radiation therapy is the standard treatment). Stereotactic needle 
  biopsy techniques may enable biopsy to be done when it could have an effect on treatment—for example, if it 
  is not certain that a mass in this area is malignant , if the tumor grows outwards and protrudes into the 
  ventricles or if there is a need to remove part of the tumor because of pressure symptoms.
• Biopsy of optic tract glioma is not always possible because it is difficult to expose the area surgically.