THURSDAY, Dec. 4 (HealthDay News) -- U.S. researchers say they've developed a hand-exercising robotic device that appears to help stroke victims recover motor skills, even more than six months after a stroke.

Brain scans suggested that the device, which patients squeeze with their stroke-afflicted hands, boosted activity in the part of the brain that handles use of the hands.

"There's still hope in these patients with chronic stroke who have had a stroke a long time ago. If they do the right type of exercises, they can get better," said A. Aria Tzika, director of the NMR Surgical Laboratory at Massachusetts General Hospital and lead author of a study released Wednesday at the Radiological Society of North America annual meeting, in Chicago.

Stroke is the third leading cause of death in the United States, trailing only heart disease and cancer, and a leading cause of severe long-term disability. An estimated 700,000 cases of stroke are diagnosed in the country each year.

In many cases, strokes cause brain damage that limits the movement of patients. In the new study, Tzika and her colleagues sought to determine whether their device could help stroke patients at least six months after their brain attacks. Conventional wisdom has held that there was only a small three- to six-month window following a stroke when rehabilitation could help a patient.

The stroke patients in the new study squeezed the device, which can be set to provide different levels of resistance. The researchers tested the device on five patients who had lost motor control in their right hands after strokes.

Brain scans using fMRI technology found that the device seemed to boost activity in the cortex, the region of the brain that corresponds with hand use, even after patients stopped using the tool.

But, Tzika said the study didn't look at whether the everyday life of the patients improved. Also, it's not clear how much the experimental device would cost.

Recovery from stroke after six months actually isn't unusual, said Dr. Argye Beth Hillis, director of the neurology residency program at Johns Hopkins University School of Medicine. "There are hundreds, if not thousands, of studies showing this," she said. "I have seen people improve with intensive rehabilitation 22 years after stroke."

Hillis added that it's difficult to know whether the device -- and not simple exercise -- was responsible for the improvements in the patients.

In another study released Wednesday at the Radiological Society of North America meeting, researchers reported that hospitals can significantly boost the number of stroke patients who get a crucial drug treatment, if they make portable CT (computed tomography) scanners available in hospital rooms.

The scanners allow doctors to more quickly diagnose whether a stroke patient is eligible to receive the drug known as tPA that dissolves blood clots in the brain.

According to the study authors, making a CT scanner immediately available could quicken diagnosis and improve by 86 percent the number of stroke patients who could be treated with tPA within the crucial three-hour window after a stroke.

More information

Learn more about stroke from the U.S. National Institutes of Health.