Answer to Question #10927 Submitted to "Ask the Experts"

Category: Nuclear Medicine Patient Issues — Diagnostic Nuclear Medicine

The following question was answered by an expert in the appropriate field:


I, like everyone else, have read a lot about radiation exposure. It's such a hot topic. I have a question regarding nuclear testing versus computerized tomography (CT) scans. CT scans expose your body to radiation mostly in the area being imaged, but nuclear tests appear to disperse the radiation throughout your body since it is injected. Does this make it safer? Obviously, more organs are exposed to radiation but at what seems a much lower dosage.


Yes, there are lots of articles every day that can make it hard to understand what are considered safe medical exams. And many base conclusions on extrapolated data that has not been seen in exposed populations.
In our field, when we estimate doses to an individual from radiation exposure, it is determined taking into account the radiation risk to the exposed organs. Doses can be compared with no regard to where the radiation originated.
Because of the short half-life of most nuclear medicine radiopharmaceuticals and because the body eliminates the radioactive material (primarily via the urine), most doses from nuclear medicine studies are lower than some x-ray studies and CT scans. Of course, the purpose of nuclear medicine studies is different from radiology studies because nuclear medicine reveals real-time, functional imaging of organs and organ systems. This is a pretty amazing look inside the body and it is obtained in a noninvasive manner.
Each specialty has its own purpose and none should be refused if it is medically necessary. All are considered safe.
Marcia Hartman, MS

Answer posted on 24 March 2014. The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.