CT-Scans

I've written before about the dangers of transparency and medical technology, at least when it comes to diagnosing back pain. Simply put, doctors tend to assume that any imaging technology with better resolution will lead to better diagnoses. But that's often not the case:

A large study published in the Journal of the American Medical Association (JAMA) randomly assigned 380 patients with back pain to undergo two different types of diagnostic analysis. One group received X-rays. The other group got diagnosed using MRI's, which give the doctor a much more detailed picture of the underlying anatomy.

Which group fared better? Did better pictures lead to better treatments? There was no difference in patient outcome: the vast majority of people in both groups got better. More information didn't lead to less pain. But stark differences emerged when the study looked at how the different groups were treated. Nearly 50 percent of MRI patients were diagnosed with some sort of disc abnormality, and this diagnosis led to intensive medical interventions. The MRI group had more doctor visits, more injections, more physical therapy and were more than twice as likely to undergo surgery. Although these additional treatments were very expensive, they had no measurable benefit.

Yesterday, the Times had a fascinating story on heart CT-scans which, like MRI, allow doctors to see all sorts of new stuff. They can detect the buildup of plaque in arteries and locate abnormalities in heart muscle. Unfortunately, the medical benefits of CT-scans have yet to be proven (arterial plaque, like spinal disc abnormalities, can also be a normal consequence of the aging process), the technology is extremely expensive and each scan subjects patients to large doses of radiation, or the equivalent of several hundred x-rays. Nevertheless, the CT-scans continue to increase in popularity:

Increasing use of the scans, formally known as CT angiograms, is part of a much larger trend in American medicine. A faith in innovation, often driven by financial incentives, encourages American doctors and hospitals to adopt new technologies even without proof that they work better than older techniques. Patient advocacy groups and some doctors are clamoring for such evidence. But the story of the CT angiogram is a sobering reminder of the forces that overwhelm such efforts, making it very difficult to rein in a new technology long enough to determine whether its benefits are worth its costs.

Some medical experts say the American devotion to the newest, most expensive technology is an important reason that the United States spends much more on health care than other industrialized nations -- more than $2.2 trillion in 2007, an estimated $7,500 a person, about twice the average in other countries -- without providing better care.