Computerize Tomography Scan (CT)

What is a CT?

Computerized Tomography, CT in short, is a sophisticated technology that can produce a series of cross-sectional images of the human body. A CT scan uses a circle of X-rays and computer analysis to create multiple images of the inner body. It is suitable for analyzing inner-body structures, including organs, bones, soft tissues, and blood vessels. CT scans produce clearer images than regular X-ray examinations. It can diagnose infectious disease, cardiovascular disease, musculoskeletal disorders, trauma, and cancers. Experienced radiologists will interpret the resulted images and write diagnostic reports after scans.

At Trinity Medical Imaging Center, our new CT scanner is an Ultra-Low Radiation Dose CT that introduces the latest CT technology to reduce patient radiation dose to only 1/6 of a standard CT. Along with O-MAR technology, it can reduce metallic artefacts.

Why 256-Slice Computed Tomography – Philips iCT Elite ?

Trinity is one of 4 medical service providers in Hong Kong using this machine. Philips iCT Elite provides superb low radiation dose and high-resolution examination with premium results. Its ultra-fast rotation time (0.27 seconds per rotation) can shorten the examination time, especially for cardiac scan patients. Equipped with the latest O-MAR technology, metal artefacts related to orthopaedic implants can also be reduced significantly.

Advantages of 256-Slice Computed Tomography – Philips iCT Elite

  • Iterative Model Reconstruction Technology (IMR) – both radiation dose and image noise reduction in all types of exam
  • Wide NanoPanel Elite CT detector – for shorter scan time and improved image quality
  • Metal Artifact Reduction for Orthopaedic Implants Technology (O-MAR)
  • Ultra fast rotation time 0.27 seconds/rotation
  • Superb low-contrast resolution 2mm @ 0.3%

How is a CT done?

The radiographer will ask the client to lie flat near the scanner gantry.


If your scan involves the abdomen or pelvis, you will be required to drink an oral contrast solution for the stomach and intestines to show more clearly in the images.

In some cases, intravenous (IV) injection of contrast agent will be required, which is typically injected into the vein on your hand. You may feel hot and sense a metallic taste in your mouth after accepting the IV injection. These sensations are normal and will disappear within a minute.

When the exam table moves slowly into the scanner, you are required to remain motionless during the whole scanning procedure. Sometimes, our radiographer will instruct you to hold your breath for the need of specific studies. The scan procedure typically lasts for 10-45 minutes. The exact time varies for different body parts.

What to notice afterwards

In most cases, you will be able to go home on your own after completing the scan. But if you have taken an IV injection and found any redness, swelling, hotness, or pain in your skin, please tell our physician immediately.

The radiographer will send a wet film and written report after the scan.

What to let us know?

Under below conditions, please tell our technician in advance of the scan:

  • Pregnant or suspect yourself being pregnant
  • Breast-feeding
  • Experienced an adverse reaction to contrast injection or other drugs previously
  • Have a history of asthma, kidney disease, heart disease, thyroid disease, allergy, or diabetes mellitus.

How to prepare?

  • Please bring your previous X-ray, CT, MRI or Ultrasound films and reports for reference.
  • No food or drinks for 4 hours before contrast CT. Regular medications can still be taken with small amount of plain water.
  • Inform our staff if you have any allergies (especially towards contrast medium), asthma, or eczema.
  • Inform our staff if you are diabetic or taking the diabetic drug “Metformin”.

Coronary Angiogram (CTCA)

  • No exercise, alcohol, smoking, coffee, tea or coke 12 hours before examination.
  • Inform our staff if you are diabetic or taking the diabetic drug “Metformin”.
  • If you are on METFORMIN (GLUCOPHAGE), please stop this drug on the day of examination and withhold it for 48 hours after the examination.
  • No food or drinks for 4 hours before contrast CT. Regular medications can still be taken with small amounts of plain water.
  • Please bring your previous X-ray, CT, MRI or Ultrasound films and reports for reference.
  • Inform our staff if you have any allergies (especially towards contrast medium), asthma, or eczema.
  • Inform our staff if you are or may be pregnant.