The War over Imaging

The War over Imaging


Joseph Schoepf, MD



The current contribution in the New England Journal of Medicine is the latest installment of articles in high profile journals that make the case against medical imaging citing concerns over increasing radiation exposure as the authors’ motivation.



It is an indisputable fact that medical imaging is on the rise. Thus, it is inevitable that radiation exposure of our patients, who are part of the general population, is increasing in step with rising imaging utilization. What are the effects on our patients? The authors of this and similar prior contributions cite the theoretical cancer risk from radiation received at medical imaging and act as if this connection was a proven fact. It is not. All estimates of cancer risk from radiation are extrapolations of data collected in WWII atomic bomb survivors. It is highly questionable whether this data can be applied to patients receiving the kind and level of radiation involved with medical imaging. Thus, that radiation from medical imaging causes cancer is a hypothesis, which yet remains to be proven.



More importantly, this, like many similar contributions only focuses on risk. Potential risk cannot be assessed without looking at the benefit side. It would be hard to find a radiologist who would argue that our specialty’s services are of no benefit to patients. However, one does not need to take our word for it. While it is true that the utilization of imaging tests is increasing, we also observe for the first time in history a much cherished decline in mortality from cardiovascular diseases and cancer, the two scourges of our time which are the major focus of medical imaging. It would be hard to argue that our increasing capabilities of applying non-invasive imaging for primary and secondary prevention and therapeutic monitoring are unrelated to this excitingly positive trend. Moreover, an increasing cancer incidence is not observed, which robs the argumentation of imaging’s opponents of its base.



Radiology has been addressing this issue for several years and the Radiology community has long been the proponent of critically evaluating benefit versus risk in deciding whether to use imaging procedures. We have evidence that it is actually not Radiology who is responsible for the sharp increase in imaging utilization but rather the self-referral patterns of other medical specialties who increasingly perform in-office imaging, increasing cost and radiation exposure. However, a national sentiment directed against the use of medical imaging is bound to hurt us. Articles such as this one should serve as a wake-up call for our specialty. The use of radiation to guide patient management and reduce doubt in Medicine is in our name, and we have used radiation for over a century for the betterment of healthcare. It is intriguing, even shocking, that none of the authors of the current contribution is a radiologist, or a medical physicist. We cannot allow other medical specialties to dominate the public discussion on the use of radiation in medical imaging. This is of particular importance in times when the field of healthcare is bound to undergo pivotal transitions. The heavy involvement of the health insurance industry in the preparation of this current contribution and their financial ties to authors of similar prior articles and editorials have received little attention but may make this and similar work seem less altruistic than the authors would like it to appear.



We do not know the biological effects of radiation from medical imaging. Because of this and because of the public fear that is created by articles such as the current one, we owe it to our patients to keep radiation dose as low as reasonably achievable. And we have gone to work on this. Hospital information systems are actively being developed that prospectively identify patients who frequently visit emergency departments with vague complaints in order to prevent unnecessary repeat imaging of such patients. The Image Gently campaign is in full swing in order to ensure that in the patients who we worry about most, our children, radiation dose is kept to a minimum. Technical innovation is rapidly responding to concerns over increased radiation exposure from medical imaging. Particularly in the arena of cardiac CT, which, because of its high visibility and destined disruptive nature in healthcare is abused as a negative poster-child by imaging’s opponents (see the accompanying editorial to the current article), dramatic reductions in radiation exposure are happening as we speak. The below is a striking example, where with the use of 2nd generation dual-source CT cardiac and non-cardiac pathology could be ruled out in a 56 year old woman with acute chest pain, obviating the need for any further workup. The scan was acquired during a single diastole and took only 270 milliseconds with a radiation dose equivalent of 1.3 mSv. Because of the various motivations that drive the current discussion on radiation exposure, this discussion will not go away soon, but with advancing technology and greater focus on the benefits of imaging will increasingly lose its base.