Editor's Note
Image Conscious
During my residency, I admitted a Kansas radiologist to the hospital for cancer surgery. As I started to listen to his lungs with my stethoscope, he asked, “Why do you bother with that? You know you get all you need to know from a chest X-ray.” I glanced at him, expecting to see a smile, but instead saw a look that said, “Listen to the wisdom of experience.” Astounded, I asked myself: Was this a burned-out doctor waxing cynical about traditional medical techniques? Or a radiologist with a one-dimensional view of diagnosis who couldn’t see farther than his view box? Yet, recently, I’ve wondered whether he was a harbinger of an attitude threatening to overtake medicine—that if you can’t image it, it doesn’t exist.
Medical imaging does tell physicians a lot, and few areas of medicine have seen the eruption of clinically useful technology that radiology has in recent years. Ultrasound has gone from a few squiggles on Minneapolis pioneer John Wild’s “echoscope” to Doppler echocardiograms that measure flow and pressure in addition to anatomy, obstetric 3-D ultrasounds that show a fetus that looks a lot like the baby that eventually comes out, and ultrasounds that guide needles and catheters for treatment in addition to diagnosis. Interventional radiology has progressed from a few radiologists doing a few angiograms to a board-certified subspecialty, with fellowship-trained doctors doing jobs previously done by surgeons (p. 28). And CT and MRI have advanced from the first EMI machines that only produced tiny Polaroid snapshots of the brain to today’s marvels that produce remarkably clear images of all bodily recesses. Few physicians yearn for the pre-ultrasound, pre-interventional, pre-CT/MRI days.
But there is a downside to all this progress. With the explosion in medical imaging has come skyrocketing costs. From 2000 to 2006, Medicare expenditures for CT, MRI, and PET scans rose 17 percent a year, from $3.6 billion to $7.6 billion. Our uniquely American approach to health care has spawned more than 7,000 MRI units nationwide, giving us more than twice as many per million people as any other industrialized nation. I estimate that there are 10 MRI machines within a centerfielder’s throw of where I practice. This expansion has not been lost on third-party payers, and many have attempted to limit the number of MRI or CT scans they will pay for. Many medical groups have countered with doctor-constructed decision-support tools to guide imaging orders (p. 14).
Imaging may have other costs besides financial ones. Since Marie Curie’s death from aplastic anemia, medicine has known the potential harm of radiation, a danger confirmed by the excess malignancies found in survivors of Hiroshima and Nagasaki. The carcinogenic potential of diagnostic X-rays remains a theoretical likelihood (p. 42). Even prenatal ultrasound is being questioned as possibly harmful to the fetus, leading to calls for restrictions on it (p. 10).
And perhaps imaging’s most occult cost was epitomized by my radiologist patient’s comment. In partaking of the wonderful harvest of imaging technology, we may be lulled into the sense that we don’t need all the other methods at our disposal to examine patients. History teaches us that new high tech can crowd out old low tech as it did in 1825, when medical history-taking withered after Laennec introduced his new stethoscope.
So I still listen to lungs, and occasionally I hear a rub that can’t be seen on an X-ray or MRI. We physicians need to use all of the tools we have, new and old, to diagnose our patients.
Charles R. Meyer, M.D., editor in chief Dr. Meyer can be reached at cmeyer1@fairview.org.