Answer to Question #12706 Submitted to "Ask the Experts"

Category: Medical and Dental Patient Issues — Diagnostic X Ray and CT

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

Q

What is the radiation dose for a child during a regular barium swallow with fluoroscopy exam with pulsed fluoroscopy? The exam was performed at a children's hospital. The internet has different doses and there is no clear answer for the average dose. I was told the dose was minimal, but some sites indicate the dose is more than 1 mSv. My son's doctor wants annual barium swallow studies. Is it safe for a child to have one barium swallow exam per year?.

A

One millisievert (mSv) is a small effective dose and you should not have any concerns about its effects. Where you live in the United States can easily result in more than a 1 mSv per year effective dose due to natural background radiation which varies due to altitude, soil composition, and building material. 

Factors that affect effective dose from fluoroscopic procedures vary significantly depending on the study being conducted. This makes the average fluoroscopy dose pretty meaningless. Those factors include patient size, which, and to what extent, organs in the patient are exposed to the x-ray beam, and the amount of time that the fluoroscopic machine is taking images. Pulsed fluoroscopy reduces the radiation dose because the x rays are being turned on and off like a strobe light, instead of always being on. Also, the fact that the procedure was done at a pediatric hospital likely resulted in a lower dose. It is normal for pediatric hospitals to "child-size" the parameters used in their diagnostic imaging protocols to reduce radiation exposure.     

The risks of health effects from radiation doses less than about 100 mSv (which includes virtually all diagnostic imaging procedures, including barium swallow exams) are either too small to be observed or are nonexistent. The benefits from properly performed clinically indicated diagnostic imaging procedures far outweigh any hypothetical cancer risk. Diagnostic medical imaging procedures provide a medical benefit to the patient even if they do not appear to reveal anything. Diagnostic medical imaging procedures also are less risky than their alternatives, such as exploratory surgery.

Even if the result of the imaging exam was negative, the physicians were provided information they could use to determine the next course of action. Refusing medical imaging procedures may result in real and substantial risk by not receiving the clinical benefits of the procedures. It might help you to ask your son's physician what will be learned from the exam each year. 

Thank you for using the Health Physics Society's Ask The Expert web feature.

Kent Lambert, CHP, FHPS

Ask the Experts is posting answers using only SI (the International System of Units) in accordance with international practice. To convert these to traditional units we have prepared a conversion table. You can also view a diagram to help put the radiation information presented in this question and answer in perspective. Explanations of radiation terms can be found here.
Answer posted on 5 February 2019. 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.