Diagnosing a CSF Leak

A doctor will obtain your medical history, perform a physical examination, and may order several tests.

For suspected spinal CSF leaks, this may include:

• MRI of the brain with contrast to look for signs of intracranial hypotension
• MR of the spine without contrast with specialized CSF leak techniques to look for possible areas of spinal leak
• Lumbar puncture (spinal tap) to measure pressure of the CSF system and send fluid samples to the lab if needed
• Myelogram, during which contrast is injected into the spinal canal by image-guided lumbar puncture; imaging by CT, MR, digital subtraction myelography (DSM), or conventional fluoroscopy is obtained to look for the site of the spinal CSF leak. Myelography is the gold-standard test for localizing the site of spinal leak.

Left: Advanced hyperdynamic CT myelogram performed to identify the site of CSF leak associated with a bone spur (arrow). Right: MR myelogram with intrathecal gadolinium demonstrating site of CSF-venous fistula (arrow).

CT cisternogram (top) and MR cisternogram (bottom) demonstrating skull base CSF leak into the right temporal bone (arrow) and middle ear.

For suspected cranial CSF leaks, this may include:

• A CT scan of the paranasal sinuses and temporal bone to detect holes in the bone that may be the cause of a cranial CSF leak
• An MRI scan of the skull base or the auditory canal with contrast to identify a cranial CSF leak; this is especially useful in patients whose symptoms are intermittent.
• CT or MR cisternogram, during which contrast is injected into the spinal canal by image-guided lumbar puncture; imaging by CT or MR is obtained to look for the site of the CSF leak
• Beta-trace protein or beta-2 transferrin test, which starts with an attempt to collect some of the leaking fluid for testing. Fluid that contains beta-trace protein or beta-2 transferrin – both of which are found in cerebrospinal fluid – is presumed to be from a CSF leak.

Dr. Park recently hosted an episode of This Is Your Brain about CSF leaks. Watch the video below: