What does the equipment look like?
The CT scanner is typically a short tube. You will lie on a narrow examination table that slides into and out of this tube. The tube is much shorter than an MRI scanner. Rotating around you, the x-ray tube and detectors are located opposite each other in a ring. The computer workstation that processes the imaging information is located in a separate control room, where the Radiographer operates the scanner and monitors your examination in direct visual contact and usually with the ability to hear and talk to you with the use of a speaker and microphone.
What will I experience during and after the CT scan?
Most CT examinations require the use of a contrast dye which is injected at the time of the scan through an intravenous line into a vein in your hand or arm. This intravenous line will be positioned by a nurse prior to the scan. The contrast is not always needed but can enhance the appearance of certain parts of the body on the computer.
A CT specialist, the Radiographer, will then take you into the scanning room where you will lie on the scanner table.
During the scan the table you are lying on will move through the scanner. Next, the table will move quickly through the scanner to determine the correct starting position for your particular scans.Then, the table will move slowly through the machine as the actual CT scanning is performed. Depending on the type of CT scan, the machine may pass several times across the scanner table you are lying on.
You may be asked to hold your breath during the scan. Any motion, whether breathing or body movements, can lead to blurring of the images
CT exams are generally painless, fast and easy. With our multi-detector CT, the amount of time that the patient needs to lie still for is reduced.
If an intravenous contrast material is used, you will feel a warm, flushed sensation during the injection and a metallic taste in your mouth that lasts for at most a minute or two. You may also experience a sensation like you would if you needed to urinate; however, this is actually a side effect of the contrast dye and subsides quickly.
With modern CT scanners, you will hear only slight buzzing, clicking and whirring sounds as the CT scanner's internal parts, not usually visible to you, revolve around you during the imaging process.
When the examination is completed, you will be asked to wait until the Radiographer verifies that the images are of high enough quality for accurate interpretation.
What are the risks of a CT scan?
During a CT scan, you are briefly exposed to ionizing radiation. The amount of radiation is greater than you would get during a plain X-ray because the CT scan gathers more detailed information. CT scans have not been shown to cause long-term harm, although there may be a very small possibility that your risk of developing cancer may increase.
CT scans have many benefits that outweigh this small potential risk. We use the lowest dose of radiation possible to obtain the required medical information. In addition to this, our modern machines and optimised techniques require less radiation than was previously required.
If you are or think you might be pregnant, you should notify your doctor in advance of your CT scan. Although the radiation from a CT scan is unlikely to injure your unborn child, your doctor may recommend another type of exam, such as ultrasound or MRI, to avoid exposing your baby to radiation.
In certain cases, your doctor may recommend you receive a special dye called a contrast dye through a vein in your arm before your CT scan. Although rare, the contrast material can cause medical problems or allergic reactions. Most reactions are mild and result in a rash or itchiness. In rare instances, an allergic reaction can be serious, even life-threatening. If you have previously experienced a reaction to the contrast dye used for particular scans, please inform your doctor.
How long will I be in the Radiology Department?
Most of the time the actual CT scanning takes less than a few minutes and the entire process is usually completed within 30 minutes.