Tests for Cranial CSF Leaks
Following a comprehensive physical exam and medical history, your doctor may order one or more of the following tests to confirm a CSF leak diagnosis or locate the leak site.
Beta-2 Transferrin Testing
Beta-2 transferrin is a protein that is only found in cerebrospinal fluid. In this test, a small amount of watery discharge from the nose or ear is collected and tested in a lab. A positive result indicates a CSF leak.
A specific type of MRI called a CISS (constructive interference in steady state) sequence MRI may be performed. This high-resolution imaging option can differentiate cerebrospinal fluid from surrounding soft tissues.
For this test, a radioactive tracer dye is injected into the spinal canal during a lumbar puncture, and the dye is tracked over time to find the location of a CSF leak. After the injection, you’ll lie down for about an hour, and then you may have blood drawn or have an X-ray, CT scan, or MRI imaging. The blood draws or imaging scans may be repeated six and 24 hours after the initial lumbar puncture.
A fluorescent dye is injected into the spinal fluid during a lumbar puncture. The dye circulates with CSF through the spinal cord and to the brain. Then surgeons open and explore an area of the skull where the leak might be, looking for the fluorescent dye. When it is found, the surgeons often can repair the hole during this procedure.
Cranial CSF Leak Repair Surgery
Surgery is often the best treatment option for cranial CSF leaks. Surgical approaches are tailored to the exact location of the leak. Once surgeons reach the leak site, they repair the hole by plugging it with tissue or fat.
For leaks on the front of the skull (anterior), surgeons may access and repair the leak through the nostrils using a minimally invasive, endoscopic approach. This technique speeds recovery, leaves no visible scars, and requires only a couple of nights’ stay in the hospital.
For leaks on the side of the skull (lateral), surgeons may access and repair the leak through incisions behind the ear, which leave less visible scarring. You’ll need to stay in the hospital for three or four nights.
Posterior and Other Approaches
For leaks on the back of the skull (posterior) or that are difficult to access through the nose or behind the ear, surgeons may perform a traditional craniotomy, which requires a larger opening in the skull. This requires a longer hospital stay, usually three to seven days.
You’ll be asked to return for follow-up visits one week after surgery and several more times at increasing intervals. You should begin to find relief from pain and other symptoms after seven to ten days.