The New Health Dialogue

When the New York Times looked East to the nuclear crisis in Japan, they deployed standard radiation doses from medical imaging studies as the scale by which to judge the nuclear plant’s radioactivity. This comparison struck an interesting parallel, but one which made the health policy team here stop and think. Instead of being relieved that the Fukushima radiation releases were on the scale of commonplace medical procedures, we asked instead, how can we be so terrified of a distant crisis – so much so that farmers in Illinois are worrying about the availability of Potassium Iodide tablets – but not afraid of the significantly greater exposures posed by CT scanning?

Sam Wainwright and Shannon Brownlee teamed up to explore this dissonant response to the risks of radiation and answer the question, “Is Fukushima scarier than your doctor’s office?” (Full article on the Huffington Post)

So why are we afraid of nuclear power, but not worried about the radiation in medical imaging tests, such as a CT scan? Here are a couple of scenarios to contemplate. Imagine waking up in the middle of the night, drenched in sweat, with an unfamiliar tightness in your chest. It could be a panic attack - you're certainly feeling panicky in the moment -- but maybe it's a heart attack, so you take yourself to the emergency room. Your tests look fine, but you're middle-aged with a gut and a smoking habit, so your doctor recommends you undergo a CT scan, just to be sure you don't have any dangerous plaque building up in your coronary arteries.

Now let's imagine a different situation. This time when you wake up in the middle of the night, it's an earthquake that jolts you out of bed, and you're a worker at the local nuclear power plant. You get a call from your supervisor, ordering you to suit up and get yourself down to the plant, which has been damaged by the quake and may be leaking radiation.

One choice seem like a no-brainer -- getting that CT scan -- while the other seems like a walk into the jaws of death, yet in both cases you would be exposed to similar amounts of radiation, about 15 millisieverts. (A millisievert is one of several ways to measure the dose of radiation.)

Other imaging tests deliver an even bigger blast. Inserting a stent, a little metal tube used to prop open a coronary artery, involves CT angiography, a kind of x-ray movie, and it can deliver up to 57 millisieverts during the course of one imaging test. That's the equivalent of standing at the power plant's gates for almost 5 hours during the peak of the crisis. 50 millisieverts is the annual limit for U.S. radiation workers. A cumulative dose of 100 millisieverts is known to increase the risk of cancer.

Radiation's harmful effects on the body are the same no matter the source, yet we see some kinds of radiation as bad and others as good. We request CT scans from doctors, but we'd have to be dragged kicking and screaming into the Fukushima evacuation zone.

The nuclear crisis in Japan can help to shift our national conversation about radiation risks away from unlikely meltdowns on foreign shores and to the real and present danger of radiation from the overuse of medical imaging technology. The irradiation of children is especially worrying:

While the academic community still debates the health effects of low radiation levels, there is growing evidence that children are at higher risk. Their smaller bodies are more sensitive to radiation than those of adults, and they have longer to live, which means more time to develop cancer. Kids are routinely exposed to adult doses of radiation, which can be twice as harmful to a young body. A head CT can deliver almost 100 millisieverts to the infant skull and operators consistently fail to adjust scanners to lower pediatric settings.

And it turns our we’re not alone in this concern. This morning, Reuters Health reported on a study in the medical journal Pediatrics that found watchful waiting caused a decrease in the number of children referred to CT scans. The study concluded “Clinical observation was associated with reduced computed tomography use among children with minor blunt head trauma and may be an effective strategy to reduce computed tomography use." Pediatricians seem to be some of the first to wake to the dangers posed by CT:

"We all want to make sure that we use CT scanning in the cases where it's likely to be positive and that we save children from the radiation for those that we know are very unlikely to be positive," Dr. Martin Osmond, of the Children's Hospital of Eastern Ontario, told Reuters Health.

As a major driver of the cost crisis in our medical system, and cause of a significant number of cancers every year, a little more skepticism and restraint in the use of CT scanning and other imaging studies is a step in the right direction in the pursuit of safe and sustainable health care.