TORONTO, Ontario — Every year, thousands of children undergo surgery for hydrocephalus, a condition where brain fluid doesn’t drain normally. Although a ventricular shunt can correct this life-threatening problem, a new study warns that nearly 30 percent of these implants break down within just two years. Now, a team in Canada says that knowing the subtle warning signs of brain shunt failure could save these children from severe complications.
Hydrocephalus typically affects young children. Fluid builds up in the brain, making a patient’s head grow larger and sometimes causing brain damage. According to UCLA Health, roughly 125,000 people are living with cerebrospinal fluid (CSF) shunts, and surgeons place 33,000 new shunts in patients every year throughout the United States. Hydrocephalus can develop at birth, or be the result of a tumor, brain bleed, or even a head injury.
The condition requires immediate treatment. Half of hydrocephalus patients will die if doctors don’t act to correct the drainage problem. Those who survive can develop serious brain damage and physical disabilities.
What is a ventricular shunt?
This implant is a thin, plastic tube used to drain the excess fluid building up and causing pressure on the brain. Surgeons connect the tube to another part of the body that can properly absorb the fluid, taking pressure off the brain. Unfortunately, children needing a ventricular shunt often need multiple surgeries throughout their lives to maintain it.
Dr. Adrienne Davis from The Hospital for Sick Children (SickKids) in Toronto notes that over a quarter of these shunts fail soon after their placement. They either break, become displaced in the patient’s body, or become blocked. Along with the near 30-percent failure rate within the first two years, another five percent of ventricular shunts fail every year after that, Dr. Davis says.
What are the warning signs of brain shunt failure?
At the Pediatric Academic Societies (PAS) 2024 Meeting, Davis revealed that there are key signs that can reveal if a child is dealing with brain shunt failure. These include very nonspecific symptoms like headaches, nausea and vomiting, and feeling fatigued.
Davis warns that shunt failure can be life-threatening for patients with hydrocephalus. Typically, a child undergoes excessive radiation scanning and sedation to find the problem, which the study author notes can be just as harmful to young patients.
With this in mind, researchers have found that a simple eye ultrasound may be able to quickly spot the signs of brain shunt failure before it’s too late. Using the child’s own healthy eye scans for comparison, Davis says comparing the diameter of the optic nerve when children are experiencing warning signs for shunt failure can expose if there is a problem with the implant. If the optic nerve sheath is swelling, the team adds that an ultrasound would be about to detect it.
“The research team is interested in finding ways to lessen radiation exposure and expedite diagnosing shunt failure in the emergency department,” says Dr. Davis, a pediatric emergency medicine research director at The Hospital for Sick Children, in a media release. “The study uses patients as their own controls by measuring the optic nerve when well and sick—a strategy that individualizes this test for every patient and recognizes that every patient with a shunt has a unique degree of shunt dependence and ability to tolerate high brain pressures.”
The new study examined 76 pairs of eye ultrasounds from nearly 60 children at the Toronto hospital’s emergency department who had the subtle symptoms of brain shunt failure. The team is now looking to confirm their promising findings in a larger group of children throughout Canada and the United States.