A CSF leak occurs when a tear or hole forms in the membrane that surrounds the brain and spinal cord. This allows the cerebrospinal fluid (CSF), which supports and bathes the central nervous system, to seep out.
The following are proven causes of a CSF leak:
- Certain head, brain, or spinal surgeries;
- Major trauma, head and spinal injuries;
- Minor trauma, such as a sneeze, a violent cough or twist;
- Placement of tubes for epidural anaesthesia or pain medications;
- Lumbar punctures and spinal taps;
- Shunts inserted for hydrocephalus and similar conditions;
- Underlying and untreated intracranial hypertension (excessive intracranial pressure); and
- Underlying connective tissue disorders, such as Ehlers-Danlos syndrome and hypermobility.
Sometimes no cause can be found or identified, but a leak is nonetheless suspected. This is known as a Spontaneous CSF Leak or Spontaneous Intracranial Hypotension (sometimes abbreviated to SIH).