Johns Hopkins pediatric neurosurgeons are continually looking for ways to make medically refractory epilepsy treatment more effective and less invasive.

To that end, neurosurgeons Risheng Xu and Shenandoah Robinson recently published a case series in the Journal of NeuroInterventional Surgery that involved four children between ages 2 and 9 who underwent endovascular embolization, also referred to as endovascular hemispherectomy. This minimally invasive alternative to traditional — or functional — hemispherectomies is indicated for patients with intractable epilepsy who may not be good candidates for traditional surgery. Like open functional hemispherectomy, this procedure can improve function and reduce seizure frequency, and it may have fewer procedure-related complications such as blood loss.

For a subset of patients whose epilepsy originates in one hemisphere of the brain, neurosurgeons can selectively embolize the affected hemisphere and cause a medically induced infarction that stops blood flow to those areas causing seizures. To sequentially embolize parts of the hemisphere, a series of procedures is performed in three or four sessions: one for the anterior cerebral artery, two sessions for the middle cerebral artery — split into two to reduce potential swelling — and one for the posterior cerebral artery.

“We don’t need a giant incision,” says Xu, who is first author on the study. “We don’t need the usual postoperative care that these traditional hemispherectomies require, which can involve a prolonged hospital stay and be very expensive.”

Three patients in the case study were seizure-free after the procedures, and the fourth, who was undergoing a palliative procedure, experienced a marked seizure reduction. The three patients demonstrated developmental and functional improvements, and none experienced hydrocephalus or unexpected complications during follow-up, with postprocedural deficits similar to functional hemispherectomy outcomes.

“These kids are usually devastated by their seizures,” says Robinson, senior author on the study. “They often have 100 or more seizures a day. They can’t develop and learn, and so getting better seizure control is the biggest priority.”

The sessions were initially six weeks apart, but were later adjusted to two weeks apart after the team saw that they could be done safely with the shorter gap between them. Patients stayed in the hospital for a few days for observation after each treatment.

Most case studies of endovascular hemispherectomy have examined one or two cases and only infants. This study of four cases and older patients further demonstrates the procedure’s utility, and widens the potential population for its use.

Because the procedure requires less intensive postop care, there is potential for surgeons in middle-resource countries who don’t have the medical infrastructure to perform functional hemispherectomy to be able to treat their patients with endovascular hemispherectomy.

The patients who underwent the procedure were supported by a multidisciplinary team of experts during recovery, including the Division of Pediatric Rehabilitation and its director, Stacy Suskauer.

“Children are growing and developing, and they’re supposed to be gaining new milestones,” Xu says, “and so to have the infrastructure here to support that process is incredibly important.”

The team also works with neurologist and stroke expert Lisa Sun and director of pediatric neurocritical care Sue Hong Routson, as well as other pediatric neurologists, epilepsy neurologists and neuroradiologists.

One patient learned to talk and socialize, and worked up to playing T-ball. Another, a girl with severe autism, is more interactive with her family and no longer requires special needs care around the clock, as she did before.

“These families faced the reality of doctors saying, ‘we don’t have anything to offer you,’ to being able to be treated and get their kid’s future back,” Robinson says.

To refer an adult patient to the Johns Hopkins Epilepsy Center, call 410-955-9441. For pediatric patients, call 410-955-9100.