It is well-known that large amounts of radiation can dramatically affect the human body. Uncontrolled radiation can cause cancer; controlled radiation can cure it. Think of radiation as being like a car. A car driven at high speeds by an untrained driver on the highway will crash and burn. A car driven at high speeds by a trained driver on a controlled track will win the Indianapolis 500. Medical imaging is like a car driven slowly, using only enough speed to get to the destination safely. There is always a chance that an accident could occur, but the chance is so small and the benefit from driving is so great that we feel assured we are doing the right thing.

Any exposure to radiation can increase your risk of cancer over your lifetime. The more radiation, the greater the risk. To put that in some kind of perspective, here's an example from the National Council on Radiation Protection. If you take 1000 people at random, 210 of them will develop cancer over their lifetimes. If you take another 1000 people and give them 5msv units of radiation per year for 40 years (that's a lot of radiation, more than most people will ever see) 218 of them will develop cancer eventually. Now, which are the 8 people that got cancer because of radiation? There is no way to say. There is no way to connect a specific case of cancer to a specific low-level radiation exposure. There is much information about radiation safety available on the internet. Much of it is good; a lot of it isn't.

The American College of Radiology and the Radiological Society of North America provide information on all kinds of imaging exams at radiologyinfo.org.

Medical radiation-both for diagnosis and therapy-is controlled by the State of Ohio Department of Health, Bureau of Radiation Protection. They publish rules that all hospitals and medical offices must follow in order to use radiation on humans. They make regular inspections of all aspects of every hospital's radiation safety program. More information about the Bureau of Radiation Protection, including all their regulations, can be found at:
odh.ohio.gov/odhPrograms/rp/radprot/radprot1.aspx.

Pregnant women are particularly concerned for the safety of their unborn children. Because you are pregnant we want you to understand the possible effects radiation might have on your child. As you read this, please remember: There is risk involved with every pregnancy. A single X-ray exam does not add significantly to this risk.

No. For there to be any effect from radiation the fetus (unborn child) must be in the direct beam. This only happens for certain kinds of exams. The fetus is not exposed during head CTs, chest X-rays, or mammograms. If the fetus is near the radiation, like for a chest CT, we can provide a lead apron for added protection.

Actual damage-either organ damage or inducing cancer-can only be caused by very high doses of radiation. All hospitals follow strict regulations to prevent radiation doses from ever getting high enough to cause any immediate problem. All X-rays, CTs included, use only low doses of radiation. There is no immediate effect from low doses of radiation. Low doses of radiation may increase the likelihood of your child developing cancer over its lifetime. However, the increase is so small that it can barely be detected. Other accidents or diseases unrelated to radiation are far more likely to occur.

As we said before, there is very little risk from a single X-ray exam of any kind. However, the risk increases if you have many exams in a short period of time. If you have had any other X-ray or Nuclear Medicine exams during your pregnancy, be sure to tell the doctor or technologist right away.

An X-ray exam is the best way of visualizing your internal organs so that a doctor can make a diagnosis. In some cases it is the only way to make a diagnosis. If a condition is not diagnosed and treated it can have an immediate effect on you and your baby.

Many CT exams use intravenous contrast, a type of X-ray dye that can make some things easier to detect. The effect of contrast on an unborn child is not known, although it is thought to be safe. The Radiologist will only order contrast if it is absolutely necessary and if your referring physician insists that the exam cannot wait until you are no longer pregnant.

MRI and ultrasound are two other imaging methods that do not use radiation. They may be used in place of X-rays for some exams, but not all. A Radiologist can tell you if there is an alternative for the type of exam you are about to have.