A Complete Guide On CT Scans And What The Procedure Entails

A Complete Guide On Ct Scans And What The Procedure Entails

Today, many health issues are difficult to detect with the naked eye-most of them are internal, including fractures, blood clots, bowel disorders, heart disease, and cancer. 

Since early detection for significant issues like cancer makes a huge difference, researchers developed the Computed Tomography (CT) scan, a diagnostic tool specifically designed to get around this obstacle and make detection much simpler and quicker. 

What is a CT scan?

CT scans are diagnostic procedures conducted with the use of machinery called CT scanners. Unlike traditional X-ray devices that sends only a single beam of X-rays through a fixed tube, these machines utilise a series of X-rays emitted from a doughnut-shaped tube that rotates 360 degrees around the patient. 

This improvement helps create many 2D images instead of a single one, and the turning motion capture makes it possible to capture many angles inside the human body.

As these X-rays pass through the body, varying amounts of them are absorbed by body tissues. Tissues that have a higher density create whiter images compared to others against the film’s black background. 

It is a non-invasive and painless method that allows medical professionals in hospitals and cancer treatment centres in Singapore to gather a great amount of detail about a patient’s diseases or injuries. The final result of the scan produces cross-section 3D images of a patient’s body and everything within it, such as muscles, organs, soft tissues and bones. 

What can it reveal about your health?

Healthcare providers typically order a CT scan to get a better idea of and conduct a more in-depth health diagnosis. This scan allows them to closely examine the internals of the body and accurately see where problems lie and any suspicious growths. Some of the issues that CT scans can detect includes: 

  • Specific types of cancer and noncancerous tumours
  • Heart disease
  • Fractures or broken bones
  • Blood clots
  • Bowel disorders like blockages or Crohn’s disease
  • Internal bleeding

How to prepare for a CT scan

If patients are advised to undergo a CT scan by their healthcare provider, they are also generally instructed to prepare accordingly. On the day of the examination, it is important to pay attention to the following: 

  • Arrival
    As much as possible, plan to arrive early or closely follow the provider’s instructions. Doing so ensures the test stays on schedule and free of complications.
  • Diet
    It is typically advised to refrain from drinking or eating anything four hours before the exam.
  • Medications
    If a patient is taking regular medications, it is recommended to consult with their healthcare provider first if it is allowed to take them before the exam.
  • Comfort
    Before entering the machine, patients are recommended to wear comfortable garments and remove all metal accessories and objects within their person, such as watches, jewellery, piercings, and clothes with metal zippers, since these can obstruct the scan.

Suppose the scan requires consuming or injecting a dye or contrast agents, such as specialised liquids that can certain features and improving the final images. In that case, there may be additional preparation guidelines, such as:

  • Blood test
    Patients may be required to take a blood test before taking the CT scan. This test helps healthcare providers choose the correct dye to use for the exam.
  • Diet restrictions
    Patients should avoid eating or drinking anything except for clear liquids four hours before the scan, similar to the regular diet restriction. This precaution prevents nausea when the contrast dye is administered.
  • Allergy medication
    Dyes or contrast agents usually contain iodine. For patients allergic to the substance, taking steroid medication on the night before the exam and the following morning may be necessary, along with an antihistamine. 

    It is recommended to check with the healthcare provider about these medications and get them to order for you if necessary.
  • Preparation solution
    Whether the contrast solution needs to be administered orally through drinking or via injection, continue following the instructions provided by the nurse or technologist.

What happens during and after the test?

Once the test begins, patients are directed to lie on their back on the CT scanner’s bed platform, and the following occurs:

  1. The bed slowly moves horizontally towards the inside of the doughnut-shaped CT scanner. Patients should stay completely still when this motion stops because any slight movement can blur the scanner’s images.
  2. The scanner proceeds to silently take pictures of the regions where more detailed information is necessary.
  3. After the exam is finished, the bed moves back out, and patients are free to exit.

CT scans typically only take about 10 to 30 minutes, but patients are advised to plan for at least an hour for the exam since most of that time is reserved for preparation. After the exam finishes, patients are generally free to resume their activities unless their healthcare provider advises that it is not safe yet.

The results of the scan will usually be available in 24 hours. The healthcare provider and a radiologist, which are physicians that specialise in interpreting radiologic images, will review the output together. After this is done, the healthcare provider will then discuss the results with the patient shortly after.


CT scans are an invaluable tool that helps healthcare professionals address a patient’s health problems, but it is more well-known for its use in detecting cancer in its early stages. 

Whether we are at high risk of developing such diseases or not, it is important to still take such exams and more specialised cancer screening tests since the disease can happen to anyone.

At ICS, we know just how devastating cancer can be. Thankfully, with the help of our cancer screening tests and early detection, getting that peace of mind is within reach. If you’re interested in getting a cancer screening test today, you can customise our range of screening packages according to your needs and preferences. 

If you’re unsure how frequently you should get checked for cancers, feel free to contact us anytime, and we’ll be glad to help.


Cleveland Clinic. CT scan (Computed Tomography): What is it, Preparation & Test details. Cleveland Clinic. (n.d.). Retrieved November 2, 2021, from https://my.clevelandclinic.org/health/diagnostics/4808-ct-computed-tomography-scan.

2. Mayo Foundation for Medical Education and Research. (2020, February 28). CT Scan. Mayo Clinic. Retrieved November 2, 2021, from https://www.mayoclinic.org/tests-procedures/ct-scan/about/pac-20393675.

3. Braizer, Y. (2018, July 24). CT scan or CAT scan: How does it work? Medical News Today. Retrieved November 2, 2021, from https://www.medicalnewstoday.com/articles/153201#what-is-a-CT-scan.