New technology gives hope to stroke and paralyzed patients

CNN
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For nearly a decade, Heather Rendulic couldn’t use her left hand to feed herself or pick up something as light as soup – but that changed when she took part in a clinical trial that could radically improve the lives of people paralyzed after an accident cerebrovascular.

The results of this trial were published Monday in the journal natural medicine.

Rendulic has a rare brain disease called cavernous angioma, an abnormality in the blood vessels that can cause a stroke. She had a series of them – five in total – over an 11-month period when she was just 22, which left her paralyzed on her left side.

“The hardest part of my condition is living one-handed in a two-handed world,” the Pittsburgh resident said.

A cerebral vascular accident cuts off the blood supply to the brain and cells begin to die within minutes. A person can be paralyzed if the stroke damages the part of the brain that sends messages to trigger muscle movement.

Rendulic eventually regained some function on her left side, but she was still unable to use a fork or clench her fist with that hand.

In 2021, in a joint project between the University of Pittsburgh and Carnegie Mellon University, researchers implanted a pair of thin metal electrodes along his neck.

Doctors are already using spinal cord stimulation technology to treat persistent pain. Research has shown that the technology could be used to restore leg movement after spinal cord injury, but hand movements are a little trickier. A properly functioning hand has unique dexterity and a wide range of motion.

For the test, scientists implanted electrodes along the surface of the spinal cord that look like strands of spaghetti. The electrodes deliver tiny pulses that stimulate specific regions and activate nerve cells inside the spinal cord.

“Sensory nerves in the arm and hand send signals to motor neurons in the spinal cord that control muscles in the limb,” said study co-author Dr. Douglas Weber, professor of mechanical engineering at the Carnegie Mellon University Institute for Neuroscience. . “By stimulating these sensory nerves, we can amplify activity in muscles that have been weakened by a stroke. Above all, the patient retains full control of their movements: stimulation is assisted and reinforces muscle activation only when patients try to move. »

This technology could work with a wide range of patients, the researchers said.

Rendulic said the stimulation feels “a bit like tickling.” It’s never painful, but it does take a bit of getting used to.

As tiny black plastic boxes light up and flashing green lights move up and down her arm, the device enables movement that would have been unthinkable years ago.

From day one, she had a new range of motion. There was no need to show her how to open her hand or reach for the arm, the researchers said. For more complex tasks, some training was required.

“When the stimulation is on, I feel like I have control over my arm and hand again that I haven’t had in over nine years,” she said.

Rendulic can raise his arm above his head, use a fork bring food to his mouth, and open it completely and close one’s fist. The other person in the trial had equally promising results.

At some point during the trial, Rendulic picked up a can of soup and released it at a marked spot on a board. The lab around her erupted in cheers, and she raised her other arm in the air in triumph.

“It’s just awesome,” she said.

The researchers also had another pleasant surprise: “We found that after a few weeks of use, some of these improvements persisted when the stimulation was turned off, indicating some exciting avenues for the future of stroke therapies.” said study co-author Dr. Marco Capogrosso, an assistant professor of neurological surgery at Pitt.

This means that even after device removal, with intense physical training, subjects may have long-term improvements, the researchers said.

No treatment is considered effective for treating paralysis six months or more after a stroke, in what doctors call the chronic phase.

The stimulation technology needs further testing, but it has great potential, the researchers said.

And this can meet a growing need. Doctors predict that one in four people over the age of 25 will have a stroke in their lifetime, and many will develop some kind of paralysis, according to the World Stroke Organization.

“There is an increasing urgency to create effective neurorehabilitation solutions for people with motor impairments after stroke,” said study co-author Dr. Elvira Pirondini, assistant professor of physical medicine and rehabilitation at Pitt.

“Even mild deficits resulting from stroke can isolate people from social and professional life and become very debilitating, with motor impairments in the arm and hand being particularly taxing and hampering simple daily activities, such as writing, eating and walking. ‘dress.”