Technology has enhanced physicians' ability to define and identify illness with ever-increasing precision. Improvements in radiation are an important part of this progress. Treatment is also uniquely benefited by radiation that is available to us as treating physicians. What happens when the diagnosis and treatments become part of the problem? Can we as physicians do better? The first use of radiation in medical diagnosis was by Wilhelm Roentgen a German physicist in 1895. At the time the radiation was called x-ray. For this accomplishment he won the first Nobel prize in physics in 1901. He used tubes to generate the radiation which was absorbed by a barium screen. This is not terribly different from today's use of barium or the iodinated contrast that I use in the cath lab. According to Wikipedia, the world's first x-ray was the hand of Roentgen's wife who is said to have exclaimed "I have seen my death." If only she could see a 3D reconstruction of a heart that today's CT scanners can accomplish. Published online in both the Journal of the American College of Cardiology and in Circulation is a conference report regarding radiation. Titled Developing an Action Plan for Patient Radiation Safety in Adult Cardiovascular Medicine (J Am Coll Cardiol, doi:10.1016/j.jacc.201201.005), it relates the findings of a meeting held on February 28, 2011 with multiple stakeholders. Exposure to radiation begins when everyone enters the hospital with the ubiquitous chest x-ray and spirals out of control the sicker you are. It is not uncommon for patients to have an extensive amount of radiation in the course of a hospitalization. This is especially important for cardiology. Cardiovascular disease is responsible for one of every three deaths in the United States. The lifetime risk for men is two in three and for women is greater than one in two. The mortality and prevalence of the illness means that many patients will be exposed to radiation for cardiovascular reasons in their lifetime. This is both good and bad. The mortality for CVD has declined by 28% from 1997-2007. Contrast this with the fact that from 1980 - 2006 the radiation dose has increased >600%. Are we getting what we are radiated for? The first problem is how do you measure the dose someone is receiving? Physicians know the dose that comes from the machine, but the effective dose can only be surmised because of the many variables involved. Further, we as physicians have no model of what happens to the human body with increasing levels of radiation. The only knowledge we have is derived from the surveyors of the atomic bombs that ended the Second World War. The effects have been measured and collated and are known as the LNT model or linear no-threshold. The problem with this is that the survivors of Nagasaki and Hiroshima had one single very high exposure. Does this correlate with our present multiple exposure over long periods of time? It appears that practice has outrun science, and the famous law of unintended consequences has come into play. Like toys that we can't get enough of, the constant x-ray exposure that patients receive is generally of little concern in the mind of the physician. They need to know what they need to know, and it needs to be done right now. All is not lost. On many levels, this problem is getting the attention that it needs. There are many stakeholders, you being one of them. You need to understand the issues and how to protect yourself. Next...where we are headed.
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