Shunt Placement Operations
The following excerpt is taken from Chapter Four of Hydrocephalus:
A Guide for Patients, Families, and Friends by Chuck Toporek &
Kellie Robinson, copyright 1999 by O'Reilly & Associates, Inc. For
book orders/information, call 1-800-998-9938. Permission is granted
to print and distribute this excerpt for noncommercial use as long
as the above source is included. The information in this article is
meant to educate and should not be used as an alternative for
professional medical care.
The following brief descriptions of typical shunt placements can provide you with a general overview of the procedures for placing a VP or VA shunt.
There are two general approaches your neurosurgeon can take when it comes to placing the proximal catheter. The first, referred to as a posterior approach, is where the proximal catheter is inserted into the lateral ventricle from an opening the neurosurgeon makes at the back of your head. The other, referred to as a frontal approach, is where the neurosurgeon places the proximal catheter into the lateral ventricle from an opening made at the top of your head, just forward of one of the cranial sutures. The terms used for the different surgical approaches are in reference to the area of the brain the proximal catheter must pass to reach the ventricles.
Before beginning the procedure, your hair will be clipped or shaved to allow the neurosurgeon an unobstructed area for the operation. The amount of hair that is clipped away depends greatly on the type of operation being performed, and upon the personal preference of your neurosurgeon.
When my son had his revisions they shaved half of his head; one time they shaved the entire thing except a stripe in the middle (when he had subdural hematomas drained and a revision at the same time). I commented to the doctor about the hair and was told that they only remove what they must and it is not done for cosmetic reasons. As soon as he got out of the hospital we shaved the rest and let it all grow in at once. In his last three revisions, only a tiny area was shaved. It looked like it would if, for example, a kid fell and needed stitches. No big deal.
The opening your neurosurgeon makes in your skull to allow access to your brain and ventricles is called a burr hole. This is a very small opening that is made using a surgical drill. Your neurosurgeon may also need to make a burr hole if you have a subdural hematoma (SDH). He would drill a burr hole over the SDH, which would allow him to relieve intracranial pressure.
The techniques described below may vary from the way your neurosurgeon performs the shunt placement operation. Consult with your neurosurgeon on the specifics of how your particular operation will be performed.
Ventriculoperitoneal (VP) shunt placement
Once your neurosurgeon has created the burr hole, his next step is to make an opening in your abdomen where the distal catheter will be placed. A small incision will be made in your abdomen, just below the rib cage, to allow your neurosurgeon access to your peritoneal cavity. The peritoneum is a membrane that covers vital organs in your abdomen, including the intestines, stomach and liver.
His next task will be to place the shunt system. Using a device called a stylet, your neurosurgeon will insert the proximal catheter through the burr hole and into the lateral ventricle of your brain. Next, he will remove the stylet and attach the proximal and distal catheters to the shunt valve. Your neurosurgeon will secure the catheters to the shunt valve using non-absorbable sutures. Once the catheters are connected, he will test the shunt system to ensure that CSF is flowing through the valve. If fluid flows through the shunt system without getting obstructed, his next task will be to place the distal catheter in your peritoneal cavity.
Your neurosurgeon will use a tunneling device to pass the distal catheter under your skin from the incision in your head to the incision in your abdomen. He will then make a very small incision into your peritoneum and insert the distal catheter.
Shaun's neck and abdomen were extremely sore after the initial placement of the shunt. He was a toddler--just 16 months old--and it bothered him greatly. I think my greatest heartache at the post-surgery time was this soreness. His head did not hurt at all, just his neck where the catheter had been passed.
With both catheters in place, your neurosurgeon will clean the areas around the incisions he has made, and will use surgical staples or sutures to close the wounds. The final step is to cover the staples or sutures with a sterile gauze bandage to help protect them from becoming infected.
Ventriculoatrial (VA) shunt placement
The only difference between a VP and a VA shunt placement procedure is the operation performed for placing the distal catheter.
To begin the procedure, your neurosurgeon will place the proximal catheter in the same fashion as described above. The proximal and distal catheters will be connected to opposite ends of the shunt valve and secured in place with non-absorbable sutures.
Next, he will need to make a small incision on your neck to allow him access to either the internal jugular vein or the common facial vein. Using a needle, your neurosurgeon will insert a guide wire and vessel dilator into the chosen vein. The guide wire and vessel dilator allow your neurosurgeon to carefully guide the distal catheter through the wall of the vein and into the right atrium of your heart. In an infant, it will be necessary to briefly expose the facial vein or internal jugular vein in order to insert the shunt.
As with the VP shunt placement, your neurosurgeon will use a tunneling device to pass the distal catheter beneath your skin between the incisions in your head and neck. The tunneling device will be removed, and the distal catheter will be slipped over the guide wire and into the vein in your neck. Your neurosurgeon will then use a fluoroscope (an imaging device that takes X-rays without using films) to ensure that the tip of the distal catheter lies within the right atrium of your heart.
Once the distal catheter is in its proper place, he will remove the guide wire and vessel dilator, and close the incision in your neck, as well as the one on your head. Your neurosurgeon may use either surgical staples or sutures to close the incisions.