Using information in medical records for more than 1,100 emergency room visits, researchers at Johns Hopkins Children's Center say they have developed a scoring tool that helps more accurately predict potential shunt failures and need for revisions in children with hydrocephalus.
An estimated 1 out of 770 babies in the United States develops hydrocephalus each year, a condition marked by an excess buildup of cerebrospinal fluid in the brain. Left untreated, the resulting pressure can cause rapid head growth, developmental delays, seizures and other ill effects.
Children's Center experts say the condition — the most common one seen by pediatric neurosurgeons — is widely treated with a ventricular shunt, a permanently implanted tube that ferries the excess fluid out of the brain fluid-filled cavities to the abdomen or other parts of the body where the excess is absorbed.
However, because the shunts need lifelong maintenance, virtually all of them fail and need revisions at some point as the child grows. Caregivers and specialists have long sought better ways to predict when a shunt is failing and when immediate medical attention is necessary by emergency medicine specialists.
New research led by a Children's Center team has resulted in a tool, dubbed the Shunt Malfunction and Triage Revision (SMaRT) Score, which is believed to be a first-of-its-kind scoring system that predicts the likelihood of a shunt failure and need for revision. The score is based on analysis of signs, symptoms and interventions gathered from 1,167 neurosurgical consultations between 2017 and 2022 at Johns Hopkins Children's Center for children ranging in age from newborn to 18 years.
A report on the new tool was published in The Journal of Pediatrics on Jan. 12, 2025.
According to Johns Hopkins Children's Center pediatric neurosurgery fellow Kurt Lehner, M.D., and pediatric neurosurgeon Eric Jackson, M.D., who led the development of SMaRT Score, it is estimated that half of shunts placed in children worldwide fail in the first two years. Shunts can fail for a number of reasons, including infection, displacement, obstruction from tissue or debris, or deterioration of the tube.
Symptoms of shunt failure can include loss of consciousness, headaches, vomiting and sleepiness that may be confused with symptoms of other more common illnesses.
When there is concern for shunt failure, families often first go to a local emergency department. These departments may do an initial screening. If neurosurgical expertise is not available at that institution, they will often reach out to a tertiary center to better assess the patient's needs.
But not all emergency rooms have the expertise to evaluate whether a shunt has failed. And with only an estimated 300–400 pediatric neurosurgeons practicing in the U.S., families, especially those living in rural areas, must often travel to get the shunt placed or get revision surgery. The uncertainty of symptoms and the scarcity of specialists have made the search for better screening a top concern of emergency medicine and other health care providers.
According to Lehner, for example, the Johns Hopkins Children's Center pediatric neurosurgery team receives about 150 to 200 requests for consultations from emergency departments each year for shunt failures. About one-quarter of those patients end up needing revision surgery; the rest are false alarms.
To address the need for a better way to predict shunt failure, the research team looked at which symptoms led patients to the emergency department for concern of failure, and which most often led to actual failure. From the data, the team developed a point system assigned to various symptoms. They concluded that headache or vomiting are each one point, since those symptoms can also be caused by common childhood illnesses. An altered mental state was assigned three points, and increased size of ventricles in the brain was assigned 10 points, because it is a more specific symptom of a shunt failure.
The research team says the SMaRT Score can predict the likelihood of a shunt failure and necessity for a consult a specialist. The more points, the higher the score, and the more likely the chance for shunt failure.
A patient with a score of three or less means that a neurosurgical consult is unlikely to be beneficial. A score of four to nine means the patient's caregiver and physician should consider a neurosurgical consult. A score of 10 or higher calls for an immediate neurosurgical consult.
Of those children in the data set, 285 ended up having shunt failure and needing surgical replacements.
From the medical records, Lehner and other experts said that the symptoms most likely to predict the need for new shunts include increased ventricle size, altered mental status, headache and time since last shunt surgery.
Of the 272 patients with a score of 10 or higher on a what-point scale, 66% of them had surgical revisions.
"Using this tool in the future could help emergency departments better decide which patients need urgent neurosurgical care and could save patients time and money from unnecessary testing and imaging," says Lehner.
Lehner and other Johns Hopkins Children's Center experts say they are continuing to collect data to refine the new tool, and hope future studies will lead to the implementation of the SMaRT Score in hospitals across the country. Lehner says the scoring system could eventually be expanded and used for other medical conditions and devices.
Other authors include Anita L. Kalluri, Kelly Jiang, Ryan Lee, Foad Kazemi, Joan Yea, Sai Reddy, Jacob Shaw and Ann Kane of Johns Hopkins, and Rama J. Alawneh with Mutah University.
This study was funded by Johns Hopkins University School of Medicine.
No authors declared conflicts of interest under Johns Hopkins University School of Medicine policies.
