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elicate lines dance across a screen mounted on the wall of the operating room. Their peaks and valleys become pronounced, suddenly flatten into a straight line — and then return, stronger than before.These digital traces represent the buzz of neurons in 12-year-old Kevin Lightner, read by two thin electrodes that surgeons have inserted deep into his brain. Kevin, who has autism and has had seizures since he was 8 years old, lies uncharacteristically still in the center of the room, draped under a blue sheet, his tiger-print pajamas neatly folded on a nearby shelf.
What’s happening in this room may be the last chance to bring Kevin’s seizures under control.
An hour and a half ago, neurosurgeon Saadi Ghatan removed a roughly 2-inch by 1-inch piece of the top of Kevin’s skull. He replaced it with a rectangular metal device, carefully screwed into the newly exposed edges of bone. The implant, a ‘responsive neurostimulation device,’ is now transmitting signals from the electrodes planted in Kevin’s thalamus. The surgeons’ hope is that the device will learn to recognize what kind of brain activity precedes Kevin’s seizures and discharge electrical pulses to prevent them — like a “defibrillator for the brain,” as Ghatan puts it. If it works, it could save Kevin’s life.
Ghatan projects the device’s readout to the screen by gently placing a black wand over the exposed metal in Kevin’s skull. The signal on the screen is surprisingly strong, given that it stems from the thalamus, a brain region that reveals its activity only weakly, if at all — and so is rarely the choice for monitoring seizures.
The rapid spiking with pauses in between echoes electroencephalograph readings the team took of Kevin’s brain before surgery. The pattern is “classic Kevin,” says his neurologist, Madeline Fields, who has donned scrubs for the first time in more than a year to get this glimpse into his brain.
Kevin was an infant when his mother, Lisa Lightner, learned he has dup15q syndrome, a genetic condition that causes epilepsy, intellectual disability and autism. Multiple types and combinations of drugs — what Lightner calls “the medication dance” — did nothing to mitigate Kevin’s seizures. Looming in Lightner’s mind were five terrifying letters: SUDEP, or sudden unexpected death in epilepsy, a constant threat to her child’s life.
Her fear led her to look for other treatments for epilepsy, and eventually to surgery. Some doctors recommended severing the two halves of Kevin’s brain to prevent seizures spreading from one side of the brain to the other. But Lightner knew two children in whom that approach had failed, and whose parents regretted opting for it. She then stumbled across a small study showing that the stimulation device lowers the odds of sudden death. After vetting surgeons in Philadelphia and Boston, Lightner sought out Ghatan, one of the few doctors in the United States who implants the device in children.
The procedure is still experimental. When the origins of epilepsy are clear, surgeons typically remove the tissue involved. But some autistic children, like Kevin, are not candidates for this because the source of their seizures in the brain is unclear. Ghatan started using the new approach to help these children four years ago. The results have been promising but limited, Ghatan says. “It’s not anything that can hold up yet from a scientific perspective.”
As he and others chart the outcome of these surgeries, though, they might learn how autism and epilepsy are related, a lingering question in the field: About one in four autistic children older than 13 also has epilepsy; conversely, having epilepsy increases the chance of an autism diagnosis roughly 10-fold. A preponderance of evidence suggests the two conditions have common genetic origins. But does epilepsy cause autism or at least alter its course? These surgeries might answer that question.
If the answer is yes, it adds urgency to the need to help children like Kevin: The sooner these children’s seizures can be brought under control, the better they are likely to fare long term.