Caleb Kumar thought he just had a headache. He was wrong.

After lying down for a nap on the evening of Jan. 18, 2011, the 14-year-old boy awoke to find that he had no sensation on the left side of his body. He was having a stroke. His parents recognized his symptoms and called 911.

Doctors would later diagnose his condition as mid-cerebral artery dissection. He would spend the next three months in the hospital and about a year undergoing intensive physical therapy to rehabilitate the muscles on the left side of his body.

Almost two years later, Kumar, now 16, has regained the majority of his motor skills and is nearly indistinguishable from other kids his age. But he's not like other kids his age.

At the time of his stroke, Kumar -- who had already earned an associate's degree in computer science from North Hennepin Community College -- was in the middle of developing a software program designed to improve the diagnosis of bladder cancer.

"Current techniques were expensive. Some of them were invasive. Some involved radiation. There were a lot of problems," he said.

"What I wanted to do was create a non-invasive, really inexpensive and effective technique that was still accurate."

The National Museum of Education announced last week that Kumar will be inducted into its National Gallery of Young Inventors in recognition of his work on the software.

Started as a sophomore

As a sophomore at Breck's Upper School in Golden Valley, Kumar had enrolled in its advanced research program, which places students in real-world settings related to their field of interest. For Kumar, whose interest was in applying artificial intelligence to improving medical diagnostics, Access Genetics in Eden Prairie was a perfect fit.

Jacob Miller, who was Kumar's biology teacher when he returned to school after the stroke, says his interest in medical science is driven by a sincere desire to improve the lives of others.

"He sees what he's doing as a way to help people," Miller said. "That's not just something he says."

While working at Access Genetics, Kumar began writing a computer program using Java Script that examines cells collected from urine samples of patients who exhibit symptoms of bladder cancer. He "taught" the program to compare certain features of these cells with features of cells that were known to be cancerous, providing a diagnosis based on this comparison.

But before he could complete the research, the stroke forced him to put his work on hold.

"It was really frustrating, because I wanted to get back into research. And I was on a good track at that time," Kumar said.

Once he was able to return to school, he completed the project and tested the program's diagnoses against those of human pathologists. The results were striking.

"I found that it performed just as well as the pathologists," Kumar said. "It was really promising."

He has since presented his project at several competitive science fairs, winning a number of awards for his research.

But Kumar, who will graduate from Breck in the spring, remains humble, Miller says. And he has no intention of resting on his laurels.

Kumar's latest endeavor is an iPhone app that enables stroke patients to track their progress during rehabilitation -- a project that is very personal for him.

"It means a lot more to me just because it's something that I experienced," he said. He will submit it to Apple for approval within a week or two.

Although doctors cannot tell Kumar what caused his stroke, he says the ordeal gave him a renewed appreciation of life and reinforced his interest in medical science.

"I think the brain is really fascinating," Kumar said. "There's so much about it that we don't know. I realized that after the stroke."

Nick Woltman is a Twin Cities freelance writer.