Tuesday, March 31, 2009

New device helps retrain the brain after a stroke

From The Baltimore Sun:

After Norris Turner's stroke a decade ago, he would tuck his right arm into his pocket to get the nearly useless limb out of the way. Now the 68-year-old grandfather from Columbia can use the arm to play catch with his grandson and hit a golf ball nearly 100 feet.

Turner's progress has made him something of a poster child for a machine called the Tailwind. It's licensed and for sale by researchers from the University of Maryland who invented it and a local entrepreneur who believed it could help patients like Turner (pictured).

"We think there is tremendous potential for this device," said Sandy McCombe Waller, who worked on the Tailwind with her colleague Jill Whitall. Both are professors in the University of Maryland School of Medicine's Department of Physical Therapy and Rehabilitation Science. Turner was a test subject.

"Mr. Turner didn't start high functioning but has been able to return to recreational activities," she said. "He can grab things with his arm, drink from a cup. They sound like little things, but they are huge things."

Strokes affect about 750,000 people a year in the U.S. and are the third-largest killer behind heart disease and cancer, according to the American Stroke Association. They are the top cause of adult disabilities.

Clamped to a table at the university, the Tailwind looks low-tech - not much more than a set of metal arms with handles. A stroke patient sits in front of it, grasps the handles and repeatedly runs them back and forth to a metronome, a steady, audible beat that facilitates movement.

Unlike a bicycle, the limbs move independently, so a weak arm cannot depend on a functioning arm.

According to two studies printed in Stroke and the Journal of the American Medical Association, patients who use the device begin to show progress after about six weeks.

The repetition retrains the part of the brain that controls motor skills but was damaged by a stroke. A stroke on the left side of the brain affects the right arm, and vice versa. Like muscle strengthening, weakened motor pathways eventually become stronger and patients make smoother movements.

The machine tilts up, the arms extend and the metronome pace increases to make it more challenging. At its toughest, it may not be a strenuous workout for a gym-goer, but eight-minute sets were exhausting for Turner.

But it has been worth it, he said one recent day as he demonstrated his routine at the university, moving his arms out and back in tandem, and then one after the other.

"Results come in spurts," said Turner, who participated in a Tailwind study two years ago and has continued working with the machine at the university and at home (researchers gave him a device).

To market the product, the inventors were matched with an entrepreneur who participated in a four-year-old program at the University of Maryland, Baltimore County that has been funded in part by a grant from the National Science Foundation. Called ACTiVATE, it trains women in business and hooks them up with technology invented at Maryland universities. So far, 25 companies have been formed, according to David J. Fink, director of entrepreneurial services for the university's research and development park, bwtech@UMBC.

Since 2005, companies have launched or are forming to sell products including DNA-based therapies for ovarian cancer, pain therapies, test kits for monitoring melanoma and a device to remotely monitor infants' and the elderly's vital signs.

Kris Appel, a former linguist at the National Security Agency, bought the Tailwind license and plans to begin selling the machines in earnest in the next few weeks through her Baltimore-based company, Encore Path Inc.

"I was convinced it was a great product," Appel said. "I knew I could sell it because I understand it. It will help so many people."

Those involved in stroke therapy say there isn't much else available for such patients. There are even fewer options that are portable and can be taken home.

The device's success in studies was notable for showing "neuro-plasticity" - recovery of brain function years after a stroke, said R. Samuel Mayer, who did not take part in the Tailwind research. Mayer is a physician adviser for the Department of Physical Medicine and Rehabilitation at Johns Hopkins Hospital and medical director of the hospital's inpatient rehabilitation.

"Traditionally, people thought that little recovery occurs from stroke after three to six months," he said. "We now know that rehabilitation can help people even years later recover some function."

He said insurance and Medicare do not recognize this, so they will not cover the therapy.

It's not clear how clinics and individuals will respond to the $2,400 price tag on the Tailwind. Formal marketing begins in the next few weeks, and none have sold yet.Mayer said other promising therapies are being studied for low- and higher-functioning patients, some of which the Tailwind researchers are involved in testing.

They include weight-supported treadmill work for legs, robot-assisted movement for arms and the use of tiny electric pulses to a part of the brain controlling motor function. There is also transcranial magnetic stimulation, which is when an electromagnet is placed on the patient's head and short magnetic pulses are used to stimulate the brain.

"The important issue is to keep patients active after stroke," he said.

Norris Turner plans to continue working on his Tailwind five days a week. He also plans to keep tossing a ball to his grandson.