Antonia Berwick, 5, of Cranberry works on writing her name during her occupational therapy session at Children's Hospital of Pittsburgh North's campus in Sewickley last week.
Click photo for larger image.
An implanted device that periodically sends electrical impulses to the brain through a major nerve in the neck will make it possible for a Cranberry girl to attend kindergarten in September.
But before classes start, Antonia Berwick is enjoying her summer to the fullest by going to the playground, swimming and, best of all, riding her purple bicycle.
"It's the first year she's ever been able to enjoy a playground and I wasn't scared she was going to split her head open or something," said her mother, Joanne. "She's actually doing typical 5-year-old stuff."
For much of her young life, seizures kept Antonia from learning, developing and simply having fun.
Even while taking medications, she had 20 to 30 overt seizures daily. A ketogenic diet, in which consumption of sugars and other carbohydrates is severely restricted, brought that daily number to fewer than 10, but doctors told Mrs. Berwick the improvement would not have been enough to heal her brain.
"They told me she would never be attending a regular school," Mrs. Berwick said. With the device, though, "she's going to a regular kindergarten. She's going to have a special-ed aide with her in the classroom, and she'll still be getting her therapies."
Antonia was born 11 weeks early, weighing just 3 pounds, 3 ounces. Despite her small size and prematurity, she hit her developmental milestones appropriately, her mother said.
"At about 10 months, I started realizing she was doing something kind of funny," Mrs. Berwick said. "It looked like she was almost falling asleep. She was having real quick head nods."
Three months later, the worried mom finally persuaded the pediatrician something was wrong by showing him episodes she'd videotaped. He immediately sent Antonia to specialists at Children's Hospital.
Because of the tape, "he knew right away they were seizures," Mrs. Berwick said. "Thank God I was persistent because they kept getting worse. We were in and out of the hospital constantly."
Some of Antonia's seizures were of the atonic or so-called drop variety, in which her head drooped and she'd fall as she lost all muscle tone. Others were tonic, where her muscles stiffened. Some were brief, others weren't; sometimes they'd cluster, and other times 30 minutes might pass between them.
Her brain was so overcome by abnormal electrical activity and post-seizure drowsiness that soon, as her mother put it, "everything was going backwards."
"Her speech started going away until finally she was totally nonverbal," Mrs. Berwick explained. "She couldn't walk anymore. She had to wear a helmet because I couldn't predict the seizures and she was hurting herself when she fell. I took her pretty much everywhere in a stroller. She was no longer dressing herself [or] feeding herself."
Worst of all, her mother said, "A lot of days she didn't know who I was."
Brain scans could not identify a focal abnormality that could be treated with surgery, and genetic testing did not reveal a known chromosomal cause for Antonia's epilepsy. A 24-hour EEG, or brain wave test, showed that she was having many, many more seizures -- a hundred every day -- than her parents observed, said Dr. Deborah Holder, director of Children's pediatric epilepsy surgery program.
Medication did not seem to help the girl, which has stayed true for about 20 percent of epilepsy patients although new drugs have become available, she added.
Antonia tried the ketogenic diet, which is high in fat and low in carbohydrates. (Even her toothpaste was special-ordered to avoid sugars.) Without enough carbohydrates to process fat for energy, the body produces ketones, residual chemicals that suppress seizure activity.
The diet reduced the number of seizures to around eight per day. But Antonia's ability to learn and develop was still impaired. As the neurologist put it, it's like trying to think through static. The brain has difficulty storing new information, or accessing information that has been stored.
"Antonia pretty much sat in her little stroller and seized," Dr. Holder recalled.
So she recommended trying vagus nerve stimulation, or VNS. Since the '90s, Dr. Holder has treated about 500 pediatric epilepsy patients, including a 6-month-old, with it. Federal officials have approved it for people 12 and older, but it has been used in younger children with success.
In a short surgical procedure, the device's electrodes are placed in one side of the neck, fused to the vagus nerve. The stimulation is controlled and powered by a half-dollar-sized processor and generator that's placed under the skin of the chest.
Settings can be changed noninvasively, with the doctor waving a wand over the device. Dr. Holder said it can take up to six months to figure out what stimulation power and cycling works best in a particular patient.
Unlike an implantable heart defibrillator, the VNS device does not kick on in response to abnormal electrical activity.
Instead, it stimulates the brain through the vagus nerve periodically, perhaps for a minute every five minutes, regardless of whether a seizure is occurring. If one does happen when the device is off, patients and their caregivers can use a special magnetized wristband to turn it on. Typically, that promptly stops the seizure.
Scientists don't know why the device works, but it seems to prevent the triggering and spread of errant electrical conduction, in effect retraining the brain.
Generally, VNS reduces seizure frequency by about 60 percent in patients who respond to it, Dr. Holder said. Even if seizure numbers don't decrease, patients may recover faster, improving quality of life.
In Antonia's case, it took about two months after her VNS surgery in October 2005 for the device to be set in a way that halted her seizures. She and her family experienced their first seizure-free day on Dec. 22 that year.
Her parents could hardly believe what they were not seeing.
"I just remember calling Dr. Holder and saying, 'Thank you for the best Christmas present you could have possibly given me,' " Mrs. Berwick said. "I got my daughter back."
Antonia was gradually weaned from her special diet and medications, and still the seizures didn't come back. Her brain wave pattern has returned to normal.
"We were so used to keeping her under constant supervision," her mother noted. "It took a long time to get a whole night's sleep. You always worried in the back of your mind."
With therapy, Antonia has gained ground during the past 10 months. She is very physically active, but her speech still needs work. Although she's the taller one, at 38 pounds she weighs about the same as her 3-year-old brother, Steven. To her mother's delight, lately she has started to fight back when he picks on her.
The device must be turned off for magnetic resonance imaging, or MRI, scans, but it doesn't stop Antonia or other patients from swimming, crossing through security gates or much else.
"She makes me crazy because she feels it [in her chest] and she plays with it," Mrs. Berwick said. "It just kind of grosses me out. But it doesn't bother her at all."
Adult-length wire was implanted during the girl's operation so the device will grow with her. In about seven years the battery will likely need to be replaced, which is a minor procedure.
Antonia might not need VNS for the rest of her life, but "we're going to leave it in and on until she goes so many years seizure free," her mother explained. "Then they'll consider shutting it off. They won't fully remove it until they're sure she will not go back to having seizures."
Anita Srikameswaran can be reached at firstname.lastname@example.org or 412-263-3858.