The conundrums surrounding medical imaging radiation dose

摘要

Question: Why is radiation dose in medical imaging so complicated and controversial? Answer: There are many reasons why this issue is quite complicated and can be quite controversial. First of all, in diagnostic medical imaging, radiation dose is not measured; it is calculated from a measurement of patient exposure. This fact is often overlooked when the resulting calculations have been performed. Next is that some aspects of the results often require interpretation, and the results in general are not patient specific. Hence, results are often expressed as average dose ranges; in addition, the meaning of the numeric results requires interpretation. An understanding of the assumptions made during these calculations is necessary and important to put these dose estimates in proper perspective. Last, it is usually desired to use these dose estimates to calculate a risk estimate. It is here that controversy often occurs because of the lack of primary scientific data, with radiologists relying instead on epidemiologic extrapolations.