Wednesday, September 2, 2009

Canadian professor develops technology to give people with cerebral palsy better speech skills

From The Globe and Mail in Toronto:

His first word was "mother," and it came at age 27.

The ability to communicate was a major step forward for Dung Le (pictured), who has severe cerebral palsy and can't control much of his movements aside from opening and closing his mouth.

Professor Tom Chau of the University of Toronto has developed a new technology that allows his patient to finally express himself in words, and it could soon help hundreds of thousands of people across North America with severe mobility problems.

It consists of an infrared camera that captures heat levels on a person's face. Prof. Chau and his team at the Bloorview Research Institute noticed an increase in those levels when a person's mouth is open and air is circulating. They hooked the camera up to a computer program commonly used by people with low mobility to type words.

On the screen, a grid with letters inside, like a keyboard, slowly cycles through the alphabet, pressing down each letter like a keystroke. When it presses the letter he wants, Mr. Le opens his mouth and the infrared camera sends a signal to type it in.

"That one motion is a switch for him," Prof. Chau said. "He's 27 and he's been looking all his life for a way to access the computer, a way to communicate, and he's really come up empty."

It took Prof. Chau's team almost two years to make the device work. In their lab in June, Mr. Le was finally able to use it. With his caregiver - his mother, Yen Nguyen - by his side, he watched the letters cycle through the alphabet, and opened his mouth to choose the right ones:

M. U. T.

"They didn't know what he was typing," Prof. Chau said.

The moment he hit the next letter, it became clear.

H.

"Are you trying to type 'mother?' " Ms. Nguyen asked excitedly, and began to cry.

E. R.

"His mom was saying, 'Oh my God, oh my God. Oh, my son,' " Prof. Chau recalled. " 'Oh, my son.' She was moved to tears. That kind of moment, it makes it all worth it."

In an interview yesterday, Ms. Nguyen said her son is able to make sounds, but trying to form words requires so much effort that his whole body breaks out in a sweat. "I've suffered a lot. I'm so happy."

There are other technologies available for severe cases like this, Prof. Chau said, but they are often invasive or difficult to manage at home.

Attaching wires to the forehead to measure eyebrow movements is one option, but it doesn't work for everyone and can be irritating. An emitter can also be pointed at the eye to detect blinking, but there's a danger it could poke patients if they have an involuntary spasm, and it's difficult to set up with enough precision.

"This is unique because it's completely unobtrusive," Prof. Chau said.

The camera is easy to use because it can capture heat even if pointed at someone from the side.

Prof. Chau estimates there are about 400,000 people with advanced mobility issues in Canada and the United States who are in need of this type of device.

"The mind is intact but they don't have any ability to express themselves," Prof. Chau said. "So you never hear about them - they're kind of an invisible population."

Prof. Chau, who holds the Canada Research Chair in pediatric rehabilitation engineering, has also invented a monitor that distinguishes swallowing motions from breathing, which is an important signal for those prone to choking because of mobility problems.

Now his Bloorview team is trying to use heat sensors to monitor someone's emotional state - something caregivers struggle every day to interpret.

It's a far cry from Prof. Chau's earlier work. Ten years ago, he left a high-paying job revamping computer systems with IBM. When his first son was born, he said, he thought hard about the contribution he could make to the world.

"I remember holding him in the middle of the night. I was looking at his face, so quiet, so peaceful, and I was thinking how lucky we are to have a healthy baby," Prof. Chau said. "I was thinking, what about all those other kids and all those other parents who are struggling? We really are so far behind in this kind of technology."

Prof. Chau is working on a home unit that is less costly. The infrared camera they are using in the lab costs $80,000, but the new prototype could go for as little as $2,000. The first model will go to Mr. Le, who should have the device delivered to his home by the fall.

The next step will be finding a company to build the device for commercial sale. Prof. Chau said he needs to convince the Ontario Ministry of Health and Long-Term Care that it should be covered under the assistive devices program. That would make the technology viable for more widespread use.

It's a long process, but Prof. Chau is happy to have gotten this far - and Mr. Le is too. "He's very eager to have some independence," Prof. Chau said.

Even after two years of experiments, "he didn't get discouraged. He was a real trooper."