Computed Tomography Tests: Process, Uses, and Risks

Computed topography tests are very useful when it comes to diagnosing various diseases. Keep reading to learn more about them!
Computed Tomography Tests: Process, Uses, and Risks

Last update: 07 June, 2021

Imaging tests like arteriography and X-rays are helpful when it comes to looking at the internal structures of the body. Specialists also use computed tomography tests (CT scans) often, which analyze the body from different angles through X-rays. This creates cross-sections.

Computed tomography tests are non-invasive. They use a scanning method to generate a two or three-dimensional image of the internal structure of an object. Medical professionals commonly use this procedure to look at internal injuries. However, there are other areas, like industry and geology, that also use it.

Multiple studies state that tomography is one of the most commonly prescribed methods for looking at people’s internal organs. This procedure has advanced since it was first introduced in 1971. Originally, it only showed images of the brain, but now it can scan any anatomical area.

Let’s take a closer look.

What do doctors look for in computed tomography tests?

This imaging test has a wide variety of uses in medicine, like oncology, cardiology, and traumatology. Also, professionals use it to diagnose and follow-up with patients suffering from a variety of conditions. In addition, it’s useful for radiation therapy planning.

Computed tomography tests show the state of both soft organs and bone tissue. Therefore, it can be used to evaluate the liver, kidneys, or brain, while also showing the bones around those organs. As a result, this one test can detect multiple issues.

Tomography is also helpful when studying spinal injuries and when evaluating bone density. In addition, it’s very useful when looking at the head, because it can detect brain bleeds.

doctor looking at computed tomography tests

Prior preparation

A CT scan is a very fast and minimally invasive procedure, so you won’t have to go through a detailed preparation for one. However, you must wear comfortable clothing, since you may need to take it off and change into a medical gown.

Also, metallic objects can alter the image in the CT scan, which would show unreliable results. Because of that, you’ll have to remove your glasses, earrings, rings, piercings, dental prostheses, or any other metal objects before the scan.

For some people, the medical professional may also apply a contrast medium to better assess a certain area. If you need a contrast, doctors recommend that you don’t drink or eat anything before the scan. In addition, you should let your doctor know if you have any allergies.

Pregnant women and people with heart, kidney, or thyroid problems should inform their specialists. All these situations increase the probability of suffering adverse effects during the test. Also, there is even a contraindication specifically for women who are pregnant.

What is a CT scan like?

First, the specialist will ask you to undress and they will give you a medical gown. If they don’t offer you one, you should wear loose clothing that doesn’t have any metal on it. Then, if you need a contrast for your test, they will administer it orally, intravenously, or through an enema.

A CT scanner is a large, donut-shaped machine with a bed and a central tunnel. The doctor will tell you to lay on your back or, in some cases, they will tell you to lay on your side or face down. The bed may also have straps and pillows to keep you in the right position. 

At the start of the computed tomography tests, the bed will move quickly to find the area that the machine needs to scan. Then, the bed will slowly go into the scanner and scan the area. In some cases, you may need to make several passes through the machine.

During the scan, you mustn’t move. That’s because any movement could cause printing errors called artifacts. Sometimes, the doctor may even tell you to hold your breath for a few seconds.

When the exam is finished, you’ll have to wait a bit for the doctor to confirm that they were able to get high-quality images. Then, your results will be ready in a short period of time. The follow-up evaluation usually lasts about 30 minutes.

Possible risks and complications

Anxiety attacks are one of the most common risks associated with computed tomography tests. This complication is very common in people who suffer from claustrophobia and in young children. Generally, the doctor will give these people a mild sedative before the scan.

In addition, this test also exposes patients to a type of radiation called ionizing radiation. Some studies link high doses of this type of energy to the development of cellular mutations. However, CT scans use very low levels of it.

Despite the radiation emitted, computed tomography is a very common and safe practice. That’s because the benefits of it far outweigh the risks. However, specialists should exhaust all other options that emit less radiation before suggesting it.

child ct scan

Understanding the results from computed tomography tests

Within a few minutes of completing the test, the radiologist will go over the results. They will usually store the images in a digital file so that you can see them on a computer screen.

The radiologist is the specialist in charge of supervising and interpreting the tests, so they are the ones who will detect any abnormalities. Once they have analyzed the results, they will draw up a report. Then, they will give that report to the patient’s physician.

More benefits than risks

CT scans are imaging tests that use simultaneous X-rays to look at soft organs and bone tissue. However, they subject people to up to 100 times more radiation than traditional X-rays, which can cause long-term risks. 

Also, the chances of damage are greater in children than in adults, since their cells reproduce at an accelerated speed. Despite all of that, this test continues to be useful when detecting multiple diseases. That’s because the benefits of this test greatly outweigh the risks.

It might interest you...
7 Organs that You Don’t Actually Need to Survive
Step To HealthRead it in Step To Health
7 Organs that You Don’t Actually Need to Survive

There are a few organs that you don't actually need to survive. In fact, over time and evolution, some have lost their function, which is why their...

  • Calzado A, Geleijns J.  Tomografía computarizada. Evolución, principios técnicos y aplicaciones. Revista De Física Médica 2010; 11(3).
  • Ramírez Giraldo J, Arboleda Clavijo C, McCollough C. Tomografía computarizada por rayos X: fundamentos y actualidad. Revista Ingeniería Biomédica. 2008; 4 (2): 13-31.
  • Espitia Mendoza Ó, Mejía Melgarejo Y, Arguello Fuentes H. Tomografía computarizada: proceso de adquisición, tecnología y estado actual. Tecnura. 2016; 20(47): 119–135.
  • Brody A, Frush D, Huda W, Brent R. Riesgo de radiación de la tomografía computarizada en niños. Pediatrics. 2007; 64 (3): 171-176.
  • Seeram E. Computed Tomography: A Technical Review. Radiol Technol. 2018 Jan;89(3):279CT-302CT.
  • Leech C. Whole body computed tomography for trauma: friend or foe? Emerg Med J. 2017 Oct;34(10):635-636.