Sunday, September 19, 2010

Robotics Helping Sroke Patients

More than half of all stroke patients suffer chronic motor impairment with a large percentage experiencing difficulty in using their hands and arms. The California Institute for Telecommunications and Information Technology (Calit2) researchers will use a five year $1.5 million grant from NIH to determine the efficacy of robot assistance in restoring fine motor skills.

David Reinkensmeyer, mechanical and aerospace engineering professor along with other researchers know that exercise after a stroke helps to restore brain pathways, but what the researchers want to know is whether the exercise is more beneficial if aided by robots. Since current therapies are designed to be administered by physical therapists perhaps the exercise would be even more beneficial if also aided by robots.

The researchers are working with local hospitals, starting with the University of California Irvine Medical Center to study possible benefits using robots in the first days after the stroke has occurred. In Orange County alone, more than 40,000 individuals have experienced a stroke.

The team will start with hand movements and will build a wearable sensor to measure patients’ movements in the days and weeks after a stroke but before the therapy begins. They will also fabricate a compact portable device to assist patients at home as they exercise the affected hand. The “smart” apparatus will build a computer model in real-time to see how much support is needed for each patient to complete the required tasks.

Reinkensmeyer envisions the sensor as a wristwatch type device that can be strapped onto the affected wrist to measure immediately how much movement occurs. In the past, he reports patients have entered studies several months after a stroke, preventing researchers from knowing how much movement the limb has already undergone.

After the patients have completed formal physical therapy, they will be randomly divided into two groups. In one group, the hand robot will assist in the limb exercises with the second group using the robot, but the robot will be programmed to give a higher level of assistance. The device small enough for home use, will provide games to encourage stroke patients to practice moving their fingers in different configurations and use different gripping techniques.

Because the severity of stroke is an important factor in recovery, all patients will undergo pre-study brain scans. These scans will determine the degree of damage to the neurons and study how the insulating material referred to as the “telephone lines” carry instructions from the brain to the muscles. The researchers hope to determine the extent to which brain imaging, sensor data, and robot-assisted exercise can predict how much limb dexterity patients can expect to regain.

According to Reinkensmeyer, the study hopes to answer three questions:

• Does the increased sensory input generated by the robot actually improve the outcome?
• Can too much robotic assistance actually decrease the patient’s effort level and ultimately his recovery?
• Does the specific combination of intact brain matter, post stroke history of hand movement, and robotic exercise predict which patients will ultimately experience the most favorable outcomes?