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An Extraordinary, Ordinary Girl A decade after radical brain surgery, Beth Usher, now 17, has made a miraculous, inspiring comeback.

April 13, 1997|By Scott Shane|| TC | Scott Shane|| TC,SUN STAFF

Since then, Beth and Mr. Rogers have regularly exchanged notes and calls; in 1991, after she wrote to him, he agreed to be commencement speaker at the University of Connecticut, where Brian Usher is an admissions officer and Kathy Usher runs the scholarship program. In his talk, he mentioned the 12-year-old Beth and quoted her proposed wording for his speech: "I am here to tell you to be friendly to everyone and to do little favors for people. Then they will like you and feel better about the world."

Scientists sometimes describe the human brain as the most complex object in the known universe. Its mysteries are yielding only slowly to scanners and scalpels. Among those mysteries is the astonishing ability of the remaining hemisphere of a young surgery patient to take over most of the functions of the excised half.

Hemispherectomy takes half of the cerebral cortex, about 40 percent of the brain's volume -- four billion of the 10 billion neurons whose electrochemical connections produce sensation, intellect, emotion, personality. It leaves untouched the lower, more primitive parts of the brain that govern such unconscious functions as respiration and heartbeat as well as gross movement of the arms and legs.

Over the past 30 years, Hopkins surgeons have performed 68 hemispherectomies for seizure disorders, the majority done since 1985 by Carson.

Most of the patients were children suffering from Rasmussen's encephalitis, in which inflammation cuts through half the brain like a slow-moving fire. The rest had intractable, one-sided seizures as a result either of birth defects or strokes.

Four patients died during or after surgery. One, who had undergone previous surgery elsewhere, remains comatose months after hemispherectomy.

Beth and one other patient recovered only after prolonged coma, a complication Carson attributes to trauma to the brain stem. To reduce the risk of bruising, he now removes the hemisphere lobe lobe instead of all at once.

That most of the patients survive and recover so completely remains a perpetual surprise even to those who watch it happen again and again. Carson, director of pediatric neurosurgery at the Hopkins Children's Center, performs hemispherectomy nearly once a month now, but he says: "If I do 1,000 of these operations, this will never become routine. I have the utmost respect for the human brain."

From the recovery of the hemispherectomy patients have come some remarkable revelations. Consider, for example, memory.

As Beth recuperated a decade ago, Brian Usher anxiously peppered her with questions, testing her recollection of vacations, cousins, arithmetic. Finally, exasperated, Beth exclaimed: "Dad, I remember everything."

She did. "It doesn't make any difference whether you take out the right hemisphere or the left hemisphere -- the patient remembers everything," says John Freeman, Beth's neurologist before and after her surgery and director of Hopkins' Pediatric Epilepsy Center. "God had the foresight to code all our memories bilaterally."

Another discovery relates to language. "Everybody knows language is coded in the left hemisphere," Freeman says. "The only thing is, that turns out to be wrong."

In fact, children who have the left hemisphere removed can understand speech immediately and gradually recover their ability to speak. So linguistic capability appears to be latent in the right hemisphere, which can take up the challenge if required.

A day after one boy's surgery, when Freeman asked about Mary Poppin's favorite word and prompted slowly with "supercalifragilisticexpiali..." the boy cut him off with "docious." The next day, he jumped in with "expialidocious." The third day, he could say the whole word.

The recovering brain, Freeman says, "is like an unmown field. The treasures are there under the grass." But it takes time and therapy to discover the pathways that lead to the treasures.

Sometimes, in the recovery room, a hemispherectomy patient will unconsciously stretch arms and hands. But the same patient cannot perform the same motion consciously with the weak hand.

The stretching is directed from the more primitive parts of the brain below the two huge hemispheres of the cerebral cortex. By contrast, deliberate, complex motion would have to be directed by the cortex, the locus of thinking and speech as well as complex motion. And if the left hemisphere is gone, it cannot issue instructions to the right hand.

"You can't use your hand if you don't know where it is," Freeman says. But gross or automatic motion of the right arm and leg, such as walking, can be controlled by the remaining parts of the brain.

What would explain Beth's short-term memory problems? Freeman's shrug reveals the limits of expert understanding.

"I don't know how much of it is a consequence of just trying to cram a whole lot into the one hemisphere she has left," Freeman says. Or, he says, it could be a result of her lengthy coma.

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