Cisternography is a type of medical imaging test used to evaluate the cerebral spinal fluid (CSF) in the brain and spinal cord. A special dye (contrast media) is injected into the spine from a lumbar puncture (also known as a spinal tap), followed by a CT or MRI scan.
It can be used to detect a leak or find blockages in the CSF pathway by examining the flow of CSF around the spinal cord and brain.