Aggressive therapies such as epilepsy surgery can be successful even in some pediatric patients with shunt-dependent hydrocephalus and recurring epileptic seizures.
SAN ANTONIO—Results from a retrospective study rule out ventricular shunt as a possible cause of seizures in some children with hydrocephalus and intractable epilepsy, according to the results of a study presented at the 64th Annual Meeting of the American Epilepsy Society.
“The overall incidence of epilepsy in children with hydrocephalus from all causes is around 30%, much higher than the general population,” Monisha Goyal, MD, Director of Clinical Neurophysiology, University of Alabama Birmingham Division of Pediatric Neurology, and from the Children’s Hospital of Alabama, told Neurology Reviews, yet “this subpopulation is largely underrepresented in pediatric epilepsy surgery case series.”
Dr. Goyal and Shenandoah Robinson, MD, FACS, FAAP, Director of Epilepsy Surgery at Rainbow Babies and Children’s Hospital, Case Western Reserve University in Cleveland, conducted a retrospective study of pediatric patients who underwent intracranial surgery for intractable seizures to determine if ventricular shunts contribute to intractable epilepsy.
Four pediatric patients with intractable epilepsy and shunt-dependent hydrocephalus from the Rainbow Babies and Children’s Hospital’s Comprehensive Pediatric Epilepsy Center were included. All were predisposed to epilepsy due to prematurity, term intraventricular hemorrhage, or severe traumatic brain injury, and all had intracranial shunts at the time of epilepsy surgery.
The researchers also noted that this patient population had challenging comorbidities that often predetermine suboptimal epilepsy surgery outcomes.
“The etiology of seizures in patients with hydrocephalus treated with ventricular shunts remains controversial,” said the investigators. “Do seizures arise from the underlying pathology, or does the ventricular catheter traversing the cortex directly incite seizure activity?”
Can Shunt Placement Cause Epilepsy or Complicate Epilepsy Surgery?
Despite the small cohort of patients, the researchers found that shunt placement–related cortical injury does not overlap with the epileptogenic zone. With careful planing and placement of subdural grids, surgery-related shunt complications can be avoided and successful outcomes may be achieved.
Three patients had neonatal seizures with perinatal injury and shunt insertion at 1 month. Another patient had seizures associated with traumatic brain injury at 3 months old with shunt placement one month later. Seizures recurred two to nine years later and persisted despite multiple medications. All but one patient had multiple shunt revisions prior to surgery.
Four to eight years after seizures recurred, epilepsy surgery was performed to guide resection of patients’ seizure foci. Drs. Goyal and Robinson did not observe any infections or other shunt-related complications associated with the epilepsy surgery.
Two patients did undergo additional resection after the first surgery, but two patients remained free of seizure five years postoperatively, and seizure frequency was substantially improved in another.
According to Dr. Goyal, “While these patients had challenging refractory epilepsies and comorbidities, some achieved seizure freedom with aggressive therapies including epilepsy surgery. We also found that the epileptogenic zone did not overlap the peri-shunt region as is the conventional wisdom.
“This leads us to conclude that though in some patients epilepsy may occur after shunt placement or is associated with multiple shunt revisions, there is another subpopulation of patients in whom shunts are not directly related to intractable epilepsy,” Dr. Goyal concluded. “The shunt insertion site may not be in the epileptogenic zone, and a shunt itself should not be a contraindication when considering candidacy for epilepsy surgery.”
—Ariel Jones