The brain is not a solid mass of tissue. It also contains cavities called ventricles, which produce cerebrospinal fluid (CSF), a clear, watery fluid that surrounds the brain and spinal cord. CSF serves many important functions. It cushions and protects the brain from injury; it delivers nutrients to nourish the brain; it removes waste from tissues; and it regulates pressure within the brain. Normally, CSF circulates through the ventricular system before being absorbed back into the bloodstream. Sometimes, however, the passage of CSF is blocked due to a tumor or cyst, a head injury, a birth defect, or an infection. When this happens, CSF accumulates inside the ventricles and causes pressure on adjacent brain tissue, a condition known as obstructive hydrocephalus.
The pressure of the excess CSF on the brain can be dangerous, so surgery is usually required to either remove the obstruction or to divert the flow of CSF into an alternate passage. For many years, the best way to divert CSF was through inserting a shunt, a permanent plastic tubing system to drain the CSF into another part of the body. Recently, neurosurgeons have developed a new technique for diverting CSF that does not require inserting a permanent shunt. Instead, tiny surgical instruments, called endoscopes, are used to view the ventricles and create a new hole in the membrane that will allow the CSF to once again circulate. This state-of-the-art procedure is called ventriculoscopy.
How ventriculoscopy works
The idea of creating a new passage within the ventricles to treat excess CSF has been around for a long time. However, new technology has made this procedure much more attractive, as endoscopic equipment and new imaging techniques such as MRIs have allowed surgeons to view the actual brain anatomy prior to and during the procedure. The endoscope is a tiny telescopic camera that is inserted into the ventricle through a small incision in the scalp and a small hole in the skull. This allows the surgeon to view the fluid and the obstruction. The surgeon then creates a hole in the membrane at the bottom of the ventricle and increases it using a catheter (small tube) with an inflatable balloon. This creates a detour for the CSF to flow around the obstruction and into the rest of the brain for re-absorption
The benefits and risks of ventriculoscopy
Ventriculoscopy has many advantages. It is a minimally invasive procedure with success rates ranging from 50% – 80% in adults and children over the age of two. When successful, it provides a permanent solution to the hydrocephalus, avoiding the need for a permanently implanted shunt. It also has a lower long-term complication rate than shunts.
The potential complications of the procedure include fever, bleeding, and temporary short-term memory loss or hormonal dysfunction. Ventriculoscopy is not usually recommended for children under two years of age, due to a higher rate of failure. Sometimes the first hole in the membrane closes up over time and the procedure must be repeated. If the ventriculoscopy fails, a shunt may still need to be implanted. The procedure is also more complicated than a traditional shunt surgery, so it is important that you have a neurosurgeon who is trained in endoscopic techniques, such as the neurosurgeons at Atlanta Brain and Spine Care.
What to expect if you or your child has a ventriculoscopy
Prior to surgery, you will have a complete physical exam, blood tests, and your health history will be reviewed. You will meet with the anesthesiologist and you will need to sign a consent form. You will not be allowed to eat or drink anything after midnight the night before the surgery. Your hair may need to be washed with a special antibacterial soap, or a small amount of hair may need to be shaved. The operation itself takes about two hours. Afterwards, you may have a mild headache.
You should contact your surgeon or your nurse if any of the following signs and symptoms occur:
- Redness, pain, swelling or drainage at the incision site
- Fever greater than 101.5 degrees F within the first six months of surgery
- Irritability or excessive sleepiness
- Nausea and vomiting
- Recurring headaches
- Blurred or double vision
- Loss of appetite
- Sudden or gradual change in personality
- Balance or coordination problems
- Rubbing of the head
- Constant downward gaze of the eyes