What is Cerebrospinal Fluid (CSF)?
Cerebrospinal fluid is a liquid that continuously flows through the brain’s hollow chambers and around the surface of the brain and spinal cord. This liquid washes out pollutants from the brain, transmits nutrients and provides protective padding to the brain and the spinal cord. The cerebrospinal fluid is contained by the meninges, which are a series of safeguarding membranes that encloses the brain and spinal cord.
What is a CSF leak?
The brain is wholly wrapped with a lining called dura. The brain and the dura are situated partially above the nose and the sinuses, which are divided from them by a thin bone. Any form of rupture in the bone and the dura can lead to a CSF leak. This can trigger the fluids to leak through the ears or nose respectively or into the spinal canal.
A CSF leak becomes evident when clear fluid starts flowing from the nose or into the back of the throat. It can arise as a result of a head injury, complication from sinus or brain injury or due to tumor removal from the inside of a sinus. CSF leakage through the ears or nose need to be detected and treated promptly to prevent meningitis, an infection of the meninges.
Types of CSF leaks
There are two definite types of CSF leaks:
It occurs when CSF starts leaking out from around the spine due to a hole in the dura. This hole can occur as a result of :
1. A tear in the bone spur
2. An abnormal link with a nearby vein
3. A bodily injury
The most common symptom of a CSF leak is headache.
When a region of the skull gets damaged or cracks, the dura is exposed and it can easily tear leading to a cranial CSF leak. Its most common signs are chronic headaches and clear liquid drainage especially from one side of the nose or ear.
What are the symptoms of a CSF leak?
- Neck or shoulder ache
- Tinnitus (ringing in the ears)
- Changes in hearing
- Nausea or vomiting
- Changes in vision
- Changes in cognition or behavior
- Clear liquid discharge from the nose or ear (on one side)
- Hearing impairment
- Metallic taste in the mouth
What are the probable symptoms that happen with or because of a CSF leak?
- Lost sense of smell (anosmia)
- Indistinct or double vision (diplopia)
- Changes in hearing
- Hearing loss
- Pulsatile tinnitus (sounds from inside the ear)
- Neck pain and stiffness
- Lack of appetite
- Dizziness or vertigo
- Nausea and vomiting
- Balance and gait problems
What are the trivial events that can lead to CSF leaks?
- Exerting to have a bowel movement
- Lifting heavy objects
Causes, diagnosis and conservative treatment for CSF leaks
The causes of a CSF leak can be summed up as:
Causes of Spinal CSF leaks –
- Lumbar puncture
An epidural in the spine to ease pain (such as during labor and delivery)
Traumatic injury to the head or spine
Bone spurs along the spine
Abnormalities of the dura around the nerve roots in the spine
Abnormal link between the dura mater and its nearby veins
Previous surgery on the spine
Causes of Cranial CSF leaks –
- Head injury
- Increased pressure in the brain
- Poorly functioning shunt
- Abnormalities of the inner ear
When to visit a doctor?
- One has constant runny nose
- One has discharge from the ears
- One has headache that aggravates when the head is upright
- One has a head injury
- One had a recent epidural
- One had a brain surgery
- One had a spinal cord surgery
When will an ENT specialist suggest a CSF leak repair surgery?
- A CSF Leak that does not improve with conservative treatment
- A severe CSF Leak that is unlikely to heal on its own
- Blood clotting in the brain or spinal cord
- Herniated brain tissue that pushes into the ears or nose
Risks and precautions
- Having a prior surgery on or around the spine area
- Suffering from connective tissue disorders (such as Masfan syndrome or Ehler-Danlos syndrome)
- Having a prior surgery on or around the skull area
- Obstructive sleep apnea
- Traumatic head injury
- Tumor at the base of the skull
- Malformation of the skull base or inner ear