CSF leak (Cerebrospinal Fluid Leak)

Diagnosis

A cerebrospinal fluid (CSF) leak can occur either in the spine or the skull. Diagnosis depends on where the leak is located and involves a combination of medical history, physical examination, and imaging tests.

Spinal CSF leak

Your healthcare professional will begin by reviewing your medical history and performing a physical examination. Tests used to diagnose a spinal CSF leak may include:

• Magnetic resonance imaging (MRI) with gadolinium: This scan uses magnetic fields and radio waves to create detailed images of the brain and spine. The gadolinium contrast highlights spinal tissues, making it easier to identify changes caused by a CSF leak.

• Radioisotope cisternography: This test measures CSF pressure and uses a special chemical injected near the spinal cord to track CSF flow. Several images are taken over 24 hours to identify possible leaks.

• Myelography: In this imaging test, contrast dye is injected into the spinal canal, and X-rays or CT scans are used to locate the leak and plan treatment.

• Spinal tap (lumbar puncture): A needle is inserted into the spinal column to measure CSF pressure. This test may also be performed during myelography or cisternography.

Cranial CSF leak

A cranial CSF leak occurs when fluid leaks from around the brain through the nose or ear. The healthcare professional will review your medical history and examine your nose and ears. If nasal discharge is present, it may be collected for lab testing.

Tests to diagnose a cranial CSF leak may include:

• MRI with gadolinium: This imaging test helps detect CSF leaks inside the brain by highlighting irregularities in brain tissue.

• Tympanometry: A handheld device called a tympanometer is inserted into the ear to measure middle ear function and check for fluid. Clear fluid from the ear may indicate a CSF leak.

• CT cisternography: Considered the gold standard for detecting cranial CSF leaks, this test uses contrast dye and CT scans to locate the exact site of the leak in the skull base. High-resolution CT scans may also be used for more detailed imaging.

Treatment

Some CSF leaks heal on their own with bed rest, while others require medical or surgical treatment depending on the cause and severity.

Treatments for spinal CSF leaks

• Epidural blood patch: A small amount of your own blood is injected into the spinal canal, forming a clot that seals the leak.

• Fibrin sealant: This is a special glue made from plasma proteins that promote clotting. It may be used alone or mixed with blood to cover the leak and stop CSF flow.

• Surgery: If other treatments fail and the leak’s location is known, surgery may be performed to close the hole with stitches or tissue grafts from muscle or fat.

• Trans-venous embolization: Used for CSF-venous fistulas, this minimally invasive procedure seals the leaking vein from the inside using medical glue.

Treatments for cranial CSF leaks

Some cranial CSF leaks, especially those caused by injury, may improve with conservative measures such as:

• Bed rest

• Elevating the head while resting

• Taking stool softeners to prevent straining

If the leak does not heal with these measures, surgical repair may be necessary to close the opening and restore normal CSF flow.