What’s wrong with this list of imaging procedures? Plenty

March 4, 2008

With success comes recognition and a certain degree of notoriety.

With success comes recognition and a certain degree of notoriety. Certainly radiology’s remarkable move into the center of the medical care process qualifies it for this status. Unfortunately, this level of recognition also turns radiology procedures into a much bigger target, with everyone from the Centers for Medicare and Medicaid Services to managed-care companies to self-interested nonprofits and, yes, even Consumer Reports magazine, taking potshots.

In its November issue, the magazine weighed in with a list of “10 overused tests and treatments.” I’ve subscribed to Consumer Reports for years and have found it to be generally reliable in its evaluation of consumer products. But I was taken aback to find that four of the overused treatments were imaging scans. The magazine didn’t include an explanation of its methodology.  

Seventh on the list was whole-body CT screening exams. CR  quoted the FDA as saying they are of no value to healthy people and expose them to unneeded radiation. Both statements are probably true, and it’s been a long time since I heard anyone seriously argue that these scans are a good thing. Still, the whole-body CT screening phenomenon collapsed in the early part of this decade. Why include it on this list?

Eighth on the list was “high-tech angiography,” what we call coronary CTA scans. CR  notes correctly that coronary CTA can noninvasively check for coronary blockages. Then it states that standard angiography is still sometimes needed to confirm blockages that might require aggressive treatment. So? When properly applied, coronary CTA eliminates costly and unnecessary cardiac catheterization. Coronary CTA is the screening strategy. Standard angio should be reserved for therapy.

Ninth on the list was “high-tech mammography,” or computer-aided detection. CR cited a 2007 study, presumably one in the New England Journal of Medicine, that found that CAD failed to improve the cancer-detection rate significant-ly yet resulted in more “needless” biopsies. Interviews of breast imaging experts reported in our June issue found little support for the NEJM study. “This study was set up to fail,” said Dr. Stamatia Destounis, a diagnostic radiologist at the Elizabeth Wende Breast Clinic in Rochester, NY.

Tenth on the list was virtual colonoscopy. CR cited a 2007 study, not identified, that standard colonoscopy is better at spotting smaller suspicious polyps. While the CT scan is less expensive, it isn’t cost-effective “because any suspicious finding requires retesting with the real thing,” CR said. What this ignores, of course, are recent data, including ACRIN results disclosed in September, finding that CT colonography is comparable to colonoscopy for large and intermediate-sized adenomas, that is, the ones most likely to be cancer. It also ignores the abominable compliance rate for conventional colonoscopy screening. CT colonography will save many more lives than endoscopic screening simply because more older adults are willing to subject themselves to it. Moreover, CT, even with radiation exposure, has a better safety profile than traditional colonoscopy, which has a nontrivial risk of bowel perforation.  

What are the common threads here? One is that some quarters harbor a lot of suspicion about “high-tech” medicine, and today’s radiology falls easily into that category. Some suspicion is justified, but it needs to be tempered with the knowledge that all medicine is continuing to evolve and new ideas and strategies deserve a reasonable hearing.

Another is that medical imaging remains at the forefront of change, always proposing and refining new and better ways to spot pathology. Although medicine is grounded in science, it is practiced by people, many of them entrenched in old ways of doing things. Radiologists as change agents are not always welcome.