Longtime U neurologist develops a test for peripheral neuropathy in people who have type 1 diabetes
Peripheral neuropathy, a painful nerve disorder that causes numbness in the hands and feet, often accompanies such diseases as cancer, AIDS, and diabetes. In fact, at least half of all people who have diabetes will eventually develop some form of neuropathy.
University of Minnesota neurologist William Kennedy, M.D., M.S., has been studying ways to diagnose and grade neuropathy for more than 40 years. Along the way, he has often been stymied when trying to assess whether a person’s neuropathy was improving or deteriorating.
“I would ask, ‘Are you better? Are you worse?’ Well, there’s no real quantitative analysis,” he says.
He was sitting at his desk pondering the problem, running his fingertips absentmindedly along his desk, when the epiphany struck.
“I could feel the little particles, or bumps, in the surface of the desk,” he says, “and I thought, ‘that could do it!’”
Several months later, Kennedy is immersed in his research project, which he calls “The Bumps.” His objective is straightforward: devise a quantifiable means for early detection and staging of peripheral neuropathy in people who have type 1 diabetes.
Working with 103 people who either had or were at risk of developing peripheral neuropathy and 166 healthy people for comparison, Kennedy fashioned a testing device that looks like a checkerboard. Inside each square are five colored circles, and embedded in one of those five circles is a miniscule “bump.” Each bump has the same diameter but a different height, ranging from 1 to 14 micrometers.
“Now when the participant rubs his index finger lightly across the checkerboard and says, ‘I feel the bump in the yellow circle,’ we know he felt it because he found it,” Kennedy explains. Each subject has to find three bumps, and the research team uses the smallest size he or she is able to find as that person’s baseline.
According to Kennedy, preliminary results indicate that his prototype is indeed an effective test for quantifying tactile sensation of finger pads and could become an important tool for diagnosing neuropathy in its earliest stages, when treatment is most likely to be effective.
Now his challenge is disseminating information about “The Bumps,” as well as the testing unit itself, to the rest of the world. He’s made some headway; the device is now used in a handful of other hospitals throughout the country. “But we need to figure out, how can we mass-produce these devices for pennies instead of thousands?” he says.
Not one to be intimidated by obstacles, Kennedy answers his own question.
“We’ll get it done,” he says. “Every project starts this way, and if you really want to get it done, you’ll do it.”