TORONTO - The Canadian Association of Radiologists wants to expand accreditation programs and bring in more peer review -- a project that appears timely in light of new investigations of medical scans at three facilities in British Columbia.

In recent years, disturbing cases also have surfaced in Saskatchewan, New Brunswick, Quebec and Newfoundland and Labrador, with concerned medical authorities announcing the need to double-check thousands of imaging scans by certain radiologists.

Some of the reviews have cost millions of dollars, and cast doubt in the minds of patients worried about the accuracy of their initial results.

Dr. Edward Lyons, president of the association, said the national organization wants to see what it can do to improve patient safety.

"Perhaps over the years we haven't done as extensive a peer review in medicine that we should have been doing, and I think it's things like this that really sort of step up the attention that people are paying to it," he said in an interview from Winnipeg.

"And that can't be anything but good, if it ultimately provides better health care and better patient care and better safety."

This month, the B.C. government said investigations had been launched into CT scans by a radiologist at St. Joseph's General Hospital in Comox, and two other radiologists who worked in Powell River and Abbotsford in the Fraser Valley.

Lyons said the association has a group that's working on the accreditation project, and examining what's already in place because they don't want duplication.

"But what we want to do is try and enhance things that they may be doing, give radiologists opportunities and ideas as to how to institute peer review in their facilities," he explained.

The association wants to bring in a full facility accreditation program as quickly as possible, he said.

"One of the provinces and some of the radiologists really would like the CAR to be the prime mover in this area. And so over the last few weeks we have been looking at what the challenges are to ramp up from two modalities that we now accredit -- bone mineral density, or BMD, and mammography -- to now encompass X-ray fluoroscopy, CT, MR (magnetic resonance imaging) and even ultrasound."

An accreditation process would examine how scans are being done.

"We want to look at making sure the equipment meets current standards, is current as far as its ability to produce quality images relative to what is acceptable and expected today, and obviously if it's in good working order with adequate maintenance," Lyons explained.

Accreditation would also ensure technologists are appropriately trained in CT and know how to deal with unforeseen events, and have adequate supervision by a physician who provides quality interpretations, he said.

"So it's really a package that we're looking at."

A program has existed for 15 years for mammography, which is used to detect breast cancer.

The association is seeking a meeting with federal Health Minister Leona Aglukkaq to discuss its plans, and "to try and get some assistance in trying to get this off the ground as expeditiously as possible," Lyons said.

In Saskatchewan, a review is underway of thousands of scans from October 2004 to December 2007 by a radiologist in the Cypress Hills Health Region in the southwestern part of the province. When 7,213 of the radiologist's scans from January 2008 to May 2010 were scrutinized, there was a variance -- different interpretation -- in 864 of them.

An earlier review of nearly 70,000 examinations done by a radiologist in Yorkton, Sask., found different interpretations on 18.8 per cent. Differences with the potential to affect patient care were found in 1,988 exams.

"That's had a real gut-wrenching impact on our profession here, in that people have been shocked to discover that variance interpretation can range as high as we have seen it," said Dr. Dennis Kendel, registrar of the College of Physicians and Surgeons of Saskatchewan.

"And to our dismay when you actually search the literature, if you press the CAR on this, they'll tell you the same, there has been relatively little research conducted worldwide into the variance of diagnostic interpretation."

Both reviews in Saskatchewan came about as a result of the province's peer review program, Kendel said.

"Its primary purpose is continuous quality improvement, so with the exception of these two instances that have arisen in the last three years, what it generates is feedback to the radiologist or other doctor doing interpretation for ways to improve his or her quality of interpretation."

He's "very keen" to hear about what the Canadian Association of Radiologists is planning, and thinks it could make a difference.

"I think it absolutely could, and we welcome anything being done by the CAR or any other agency to propose an effective strategy," he said.

"We know that no province is doing anything comparable to what we're doing -- there are small pockets of review that are going on, and some of them are even better than ours, but there's no other province doing it provincewide."

William Hendee, distinguished professor in radiology at the Medical College of Wisconsin in Milwaukee, said double reading of images to verify that exams were read correctly hasn't found its way into the accreditation process in the United States yet.

"That's very intrusive into the prerogatives of the individual physician. I'm sure in the U.S. if this were proposed, in the U.S. there would be a backlash from the physicians who would not want to have their judgments subject to verification by another physician," he said.

"I'm not saying it's a bad idea. I'm just saying that I can see that there would be quite a pushback."

However, he said everyone can benefit from being held to a higher level of accountability.

In terms of reading scans, Kendel said that imaging has become incredibly more complex in recent decades.

"I graduated in medicine in 1971 -- the only thing available then was standard X-rays and it was a question of looking at two or three or four or five images," he said.

"And now CT studies, for instance, can generate hundreds of images because they take all these slices, and then you can rotate the image on a screen so you can look at it from different angles, so quite frankly, the task of interpreting a CT study is infinitely more complex than doing simple X-ray interpretations."

Hendee, who specializes in medical physics, said there are five sellers of CT equipment, and they all have different models with different information on protocols.

"The difficulty is that that information is oftentimes outdated, and it doesn't track developments on the equipment, or add-on features to the equipment, so this really needs to be done, not by the vendors, but it really needs to be done by people in the field who are involved in the application," he said.

An institution applying for accreditation would be forced to look at the protocols, procedures, and education and training of technologists and doctors doing the interpretations, he said.

Patients in some U.S. facilities where suboptimal protocols were being used have received very high doses of radiation, Hendee noted.

Lyons commented recently on a study that found heart attack patients exposed to greater amounts of low-dose radiation from X-rays, CT scans and nuclear medicine had higher cancer rates than heart attack patients with less exposure.

"There is likely some overuse of CT scans because they are so readily available," he said. "Most tertiary care facilities have them running 24-7."

Operators need to be well trained to set up the machine properly, limit the dose properly and recognize if there's a problem with the machine and it's delivering a dose that's too high, Lyons said.

The Canadian Association of Radiology is working with the National Research Council on a dose registry and radiation exposure monitoring project, he said. Information on radiation exposure would be transmitted to a central location and there would be a feedback mechanism to let health-care professionals track exposures in patients, he said.