04 July, 2006  01:32 GMT
Doctors have proof that a man who was barely conscious for nearly 20 years regained speech and movement because his brain spontaneously rewired itself by growing tiny new nerve connections to replace the ones sheared apart in a car crash.
Terry Wallis, 42, is one of the few people known to have recovered so dramatically so long after a severe brain injury. He still needs help eating and cannot walk, but his speech continues to improve and he can count to 25 without interruption.
Decades of Amnesis
Wallis' sudden recovery occurred three years ago at a rehabilitation center in Mountain View, Arkansas. Doctors have said that similar results are not possible for people in a persistent vegetative state. Nor do they know how to make others with less serious damage, like Wallis, recover.
"Right now these cases are like winning the lottery," said Dr. Ross Zafonte, rehabilitation chief at the University of Pittsburgh Medical Center, who was not involved in the research. "I wouldn't want to overenthuse family members or folks who think now we have a cure for this."
Wallis has complete amnesia about the two decades he spent barely conscious, but remembers his life before the injury.
"He still thinks Ronald Reagan is president," his father, Jerry, said in a statemen. He added that until recently, his son insisted he was 20 years old.
Brain Cells Had Not Died
The research on Wallis, published Monday in the
Journal of Clinical Investigation, was led by imaging expert Henning Voss and neurologist Dr. Nicholas Schiff at the Weill Medical College of Cornell University in New York City. Doctors at JFK Medical Center in Edison, New Jersey, also participated.
Wallis was 19 when he suffered a traumatic brain injury that left him briefly in a coma and then in a minimally conscious state for more than 19 years. He was awake but uncommunicative, except for occasional nods and grunts.
Wallis' condition differed from that of Terri Schiavo, whose brain cells had died. In Wallis' case, "the nerve fibers from the cells were severed, but the cells themselves remained intact," said Dr. James Bernat, a neurologist at Dartmouth-Hitchcock Medical Center in New Hampshire, who is familiar with the research.
Nerve cells that have not died can form new connections; for example, nerves in the arms and legs can grow about an inch a month after they are severed or damaged. However, this happens far less often in the brain.
Took Time to Build a Network
Wallis seemed to make a sudden recovery when he began speaking and moving three years ago, but he actually may have been slowly recovering all along, The new research suggests, as nerves in his brain formed new connections at a glacial pace until enough were present to make a network.
Researchers used a new type of brain imaging only available in research settings -- not in ordinary hospitals or rehabilitation centers -- to establish the regrowth. It tracks the direction of water molecules in and around brain cells, an indicator of brain activity.
"It's a roadmap of how the connections are running," said Schiff.
Doctors compared Wallis' brain function to that of 20 healthy people and another minimally conscious patient who showed virtually no recovery for six years. All were imaged twice, 18 months apart.
In Wallis' brain, "what we first see is how overwhelmingly severe this injury was," with many abnormalities compared to the healthy people, Schiff said.
The second set of images showed changes from the first, strongly suggesting that new connections had formed. These correlated with areas of the brain that affect the ability to move and talk.
Not Just a Matter of Time
The other minimally conscious patient -- a 24-year-old man who suffered a severe brain injury in a car accident when he was 18 -- also showed evidence of changes in nerve connections, but they were not organized in a way that made a difference in his ability to function.
"We'll have to understand more about why recovery occurred [in Wallis' case]," Zafonte said. "The question is 'why?' It's not just 'wait.'"
Until that question is resolved, imaging cannot be used to predict who will recover or to help patients' brains rewire, he said.
The Charles A. Dana Foundation, which finances brain research, funded the scientific work. The lead author, Voss, also received money from the Cervical Spine Research Society, whose sponsors include companies that make spine care products. The British Discovery Channel and HBO paid to fly Wallis and family members to Cornell for tests.
"Most neurologists would have been willing to bet money that whatever the cause of it, if it hadn't changed in 19 years, wasn't going to change now," Bernat said. "So it's really extraordinary."
Wallis is now able to make jokes, according to his father. "That was something he wasn't able to do early in his recovery," Jerry Wallis said. "He now seems almost exactly like his old self. And he very often tells us how glad he is to be alive."
(c) 2006 Associated Press. All rights reserved.
(c) 2006 Daily News Central. All rights reserved.
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