Health
Fact-checked

At WiseGEEK, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

How Safe is a CT Scan?

K T Solis
K T Solis

Computerized tomography, also known as a CT scan, has been used since 1971 to detect disease in people and provide guidance as to how the disease should be treated. A CT scan is generally considered safe to use; so safe that doctors consider it one of their most trusted pieces of medical equipment. This x-ray procedure is painless and commonly used in hospitals. During the scan, several images are taken. After this occurs, a computer organizes the images into detailed pictures of bone, tissue, and blood vessels.

When a patient undergoes this procedure, he or she is exposed to a small amount of radiation. This radiation is used to take a picture of the patient's internal organs. Once the scan concludes, no traces of radiation remain within the body. The image captured by the CT scan is an accurate, detailed picture that permits the doctor to diagnose and pinpoint an array of medical conditions.

The CT scanner is generally considered one of the safest pieces of medical equipment.
The CT scanner is generally considered one of the safest pieces of medical equipment.

As technology has improved throughout the decades, so has the performance of the CT scan. The images that newer scans create are so detailed that less radiation is required. Despite the benefits of the scans, some scientists worry that the increased use of this equipment can lead to more cases of cancer. Since large amounts of radiation have been known to cause cancer, some scientists feel these scans are being used too much.

A CT scan is a painless, commonly used X-ray procedure.
A CT scan is a painless, commonly used X-ray procedure.

Scientists and doctors have differing opinions as to the safety of CT scans. Doctors are convinced of its benefits because only a small amount of radiation is used in a scan. To date, no cases of cancer have been linked to the use of CT scans. In fact, many doctors feel that the benefits of using the equipment far outweigh the potential dangers of using them. This is because the radiation doses used in the scan are lower than those that have been actually linked to cancer.

Receiving multiple CT scans can put patients at a higher risk for developing cancer because of the increased exposure to radiation.
Receiving multiple CT scans can put patients at a higher risk for developing cancer because of the increased exposure to radiation.

Despite these facts, patients are discouraged from requesting a scan unless they display symptoms that would benefit from being studied through images captured by a CT scan. The scans are not infallible, however. Diseases like diabetes can't be diagnosed by reviewing a CT image. If a patient is scheduled to have a CT scan, he or she should consult with the doctor to determine why the doctor has recommended one. Although doctors consider the procedure risk-free, this doesn't mean that radiation should be used without good cause.

Discussion Comments

anon999837

I am concerned because the last I read a CAT scan had 200x the amount of radiation that one X-ray had. And, I read that in Europe the CAT scan is banned due to radiation concerns.

My husband has had a heart transplant, and so is on immunosuppressive therapy. He is 73 years old. This is his 16th year as a transplant. Given his suppressed immune state, I fear he has a much greater risk for cancer from the CAT scans.

He had one CAT in August of 2017, and now they are wanting to do FOUR more CAT scans in the next week on him.

I asked the vascular surgeon if another test, possibly an MRI or MRA would do as well. He said no. That the CAT was the gold standard. I asked even given the increased risk for cancer. He said yes. (he has an aneurism, less than 5cm...there is concern that he may have a family history for aneurisms. He previously had a AAA repair 14 years ago, and the graft site appears to be degrading.)

Should I get a second opinion? And if so, from whom?

anon305122

@anon167994: It would depend on what they were imaging and how they were going about it.

We always try to limit exposure to patients as much as possible, however CT scans are also incredibly valuable for diagnosing illness and staging disease.

Feeling sick and vomiting after a scan would most likely be caused by a minor reaction to any contrast used during the procedure. It could also simply be stress as having an exam can indeed be quite stressful.

If you are at all concerned, there is nothing wrong with talking to your doctors about it. Ask them why they need to perform another CT and if there are any exams they could do that would not involved ionizing radiation (such as an MRI or ultrasound). Depending on what they are looking for, this may or may not be possible.

As for actual damage caused by the CT, talk to the radiologist if possible, and they should be able to explain possible problems that could occur from exposure to radiation. The less radiation you are exposed to, the better. That being said, odds are very very low that four scans could lead to any long term problems.

Talk to your doctor. It is their job to make sure you understand the examination and to answer any questions or concerns you have regarding it.

anon167994

How bad is it for my body to have three CT Scans within a four-week period. They are thinking of another one which would make it four in a six-week period. I always feel sick after and vomit. I am worried about long term effects.

anon136814

My mother is a diabetic patient. She has fever and back ache for which a dumb doctor has suggested she go for a CT scan.

I'm telling you: after taking the contrast she lost her breath, vomited, her face was swollen, tongue has come out of her mouth and slight blood oozed from her mouth. she has to be admitted in ICU for two days. It's a complete close shave for her.

Please be very careful and assess the risk before you take the contrast for the CT scan.

anon129311

I've had five ct scans in three years and they found nothing. I'm worried about getting cancer from it.

anon111938

I am trying to find out the same question as well? Including another CT scan soon. Should I find out, will let you know. Dirk

anon71771

do ct scans cause cancer in as little as five years?

Post your comments
Login:
Forgot password?
Register:
    • The CT scanner is generally considered one of the safest pieces of medical equipment.
      By: beerkoff
      The CT scanner is generally considered one of the safest pieces of medical equipment.
    • A CT scan is a painless, commonly used X-ray procedure.
      By: svedoliver
      A CT scan is a painless, commonly used X-ray procedure.
    • Receiving multiple CT scans can put patients at a higher risk for developing cancer because of the increased exposure to radiation.
      By: Monkey Business
      Receiving multiple CT scans can put patients at a higher risk for developing cancer because of the increased exposure to radiation.