After eight years spent fine-tuning a minimally invasive brain surgery technique, Sandeep Sood, a neurosurgeon at Children’s Hospital of Michigan, has successfully used this new approach in six surgeries on children to help control their intractable epileptic seizures. The technique, featured in a recent issue of the Journal of Neurosurgery Pediatrics, reduces the size of the incision site to an inch and combines two commonly used surgical instruments in one tool.
Of the 750,000 American children diagnosed with epilepsy, more than half—about 460,000—have “active epilepsy,” with seizures that can be debilitating and life threatening. Medications only control the seizures in about two-thirds of those patients. For the remaining one-third, two surgeries have become most frequent: the corpus callostomy, in which the bridge between the two hemispheres of the brain is severed, and the hemispherotomy, in which a damaged hemisphere (or portion of it) is removed. (This procedure is also known as a hemispherectomy, and it often has remarkable results, as we wrote about in October.) Over time, seizures appear to cause damage to the hippocampus, amygdala, and piriform cortex.
“There is a group of children for whom the seizures start on one side of the brain, and for whom that side of the brain does not function,” says Sood. “When we disconnect that side of the brain that is nonfunctional but causing seizures from the healthy part of the brain, the seizure doesn’t reach the healthy, conscious part of the child’s brain, even if he has a seizure.”
These surgeries are often the only hope for controlling or stopping seizures in these children, but historically they have been invasive, with blood loss a significant risk during the lengthy surgery. Moreover, even with successful procedures, the recovery has been painful and long. “Fifteen years ago, we used to make a big incision from the hairline just above the forehead to the ear, maybe six to eight inches,” he tells mental_floss. “This procedure would require up to eight hours, blood transfusions, and hospital stays of 10 to 14 days.”
Sood's technique and tools represent a new approach: “We do this operation with a small incision, just about an inch in size, with no need for blood transfusion,” he says.
The endoscope is a small flexible tube-like device with a camera on it. “In the past, the endoscope was used in a way that you’d have to have someone hold it, or use a holder," Sood says. "In brain surgery, you need both hands to dissect. You would have to reposition the endoscope every time you removed or reintroduced the instruments.”
Sood has attached the endoscope to a suction device that removes blood and other fluid to keep the visual field clear. Where the suction tool goes, so does the endoscope. Plus, newer endoscopes are more powerful, with 3D capabilities, and provide greater magnification of the tissue, which is helpful when working inside the smaller brains of children.
As recounted in the study, Sood used this new approach to perform corpus collostomies on four pediatric patients with drop attacks and hemispherotomies on two with intractable seizures. The procedures were successful in all patients. None required a blood transfusion.
Six months after surgery, the patients who underwent corpus callosotomy were free of drop attacks. The patients who had hemispherotomies were seizure free.
Even before they perfected this minimally invasive technique, says Sood, these children often saw an improvement in their cognitive skills once the nonfunctional brain tissue, and the stresses of seizure, were removed from the healthy parts of the brain. Now they can also have less postoperative pain and shorter stays in the hospital after surgery, of just a few days. These advances make the procedure possible for more children.