The 84-year-old Mississauga resident was dangerously anemic from internal bleeding. He had undergone half a dozen uncomfortable scopes and scans, including endoscopies, colonoscopies and barium X-rays. But doctors still hadn't pinpointed the source of the bleeding.

Hsu had to be transfused with eight units of blood each month just to replace what he was losing. The blood loss made him feel light-headed and lethargic.

The next step was exploratory surgery, a major operation that would involve a six-week recovery, but Hsu balked at the prospect.

Then doctors suggested a new diagnostic option: swallowing a capsule with a miniature camera inside it. Hsu agreed to try it.

Every year, thousands of Canadians undergo procedures to examine the small bowel. Usually it takes several tests and sometimes surgery to figure out what's wrong. Potential problems can include diseases of the small intestine such as Crohn's or celiac disease, irritable bowel syndrome, ulcers, tumours and leaky vessels.

But the small intestine is pretty much uncharted territory for doctors because it is hard to see with conventional imaging tools. Physicians can examine the gastrointestinal tract with a flexible, camera-equipped instrument called an endoscope, either from the colon up, or the throat down. Neither procedure can reach the entire small intestine, however, which is 21 feet long.

Dr. Robert Clark, head of gastroenterology at the Trillium Health Centre in Mississauga and Hsu's doctor, calls the video pill "revolutionary."

"The capsule really does fill a large void diagnostically compared to what was available previously for small bowel pathology."

Invented by a former guidance missile designer, the system fits a wireless video camera, transmitter and battery into a capsule about the size of an oversize vitamin pill.

The technology, developed by Given Imaging Ltd. in Israel, is in use in 41 countries, including Canada, the U.S. and countries in Europe, Central and South America and Asia. In Toronto, the capsule is available at Beresford, a private clinic located at Trillium, and another private clinic in Thornhill. St. Michael's Hospital and Mount Sinai Hospital offer the procedure as well, though primarily to patients in clinical studies.

Clark has used the pill with three patients, including one in whom the capsule helped to detect a tumour, and has several more lined up for the procedure.

Dr. Khursheed Jeejeebhoy, a gastroenterologist at St. Michael's hospital, said there is no sedation involved and no discomfort for the patient. The ease with which the test can be administered is exciting for both physicians and patients.

Since 1999, about 44,000 patients worldwide have undergone capsule endoscopy. The procedure costs $2,500 and is not covered by OHIP. The pill is under review by OHIP, which typically bases any decision to cover a new technology by comparing its costs and benefits with conventional tests.

Because it is still relatively new, the capsule is mostly used only after conventional scans have failed, said Clark. Patients should still have more traditional tests first, he said.

European studies have consistently shown that the capsule identifies a cause of bleeding in up to 80 per cent of cases, with an unsuspected small bowel tumour found in up to 10 per cent of patients. That is twice as accurate as endoscopy and 12 times more accurate than X-rays of the small bowel.

Hsu took the plastic pill after a 12-hour fast. "It was alive and flashing, like something out of a sci-fi movie. I swallowed it easily though," he said

Hsu wore a battery pack and a Walkman-size recording device, attached to his waist by a Velcro belt. Electronic leads were attached to his torso. Over the next eight hours he carried on with his daily activities as the capsule made its way through his body, taking 55,000 flash pictures — two per second — and transmitting them to the recording device. The camera's field of vision is 140 degrees and it magnifies eight times.

"I couldn't feel anything. It was amazingly simple and exciting, actually," said Hsu.

The single-use capsule passed out of his system naturally after 24 hours. After Hsu returned the gear, Clark loaded the data into the computer. The images of his insides came across the screen like scenes from the 1966 sci-fi film Fantastic Voyage, where doctors travel around the body in a miniature submarine.

His intestine appeared as a white-walled pulsating tunnel, patterned with blood vessels. Then, 90 minutes into the capsule's descent, the screen displayed four prominent leaking vessels.

Looking like cherry red craters, they were under the lining of the bowel.

The condition, known as angiodysplasia, was treated by cauterizing the vessels using an endoscopic probe.

"My prognosis is good. I feel much better. I have a lot more energy now," said Hsu.

The capsule is not for everyone. Pregnant women, people with pacemakers, swallowing disorders or intestinal narrowing aren't candidates. And there can be glitches: The camera may fail to flash, leaving gaps in the images or, in rare instances (less than 1 per cent of cases), endoscopy or surgery is required to retrieve a marooned pill.

In addition to causing less discomfort and anxiety for the patient, earlier diagnosis with the capsule is also cost-efficient, said Clark.