CT Scanning
- About CT Scanning
- What is involved with having a CT Scan?
- Is CT safe?
- Is CT painful or uncomfortable?
- Can I be with my child during the CT Scan?
- Does my child need to fast?
- Where do I go and how long will it take?
- What if my child is sick or I am unable to keep the appointment?
- When will I receive the result?
- CT example images
- For more information
About CT Scanning
The CT (computerized tomography) scanner uses x-rays to produce cross-sectional pictures of the body. It enables the radiologists to view images of a specific region of the body in detail. With brain CT scans, the pictures of the skull and brain are arranged in slices form top to bottom.
What is involved with having a CT Scan?
CT Scanning is similar to having a regular x-ray, except the equipment is larger and more technical. Your child will be asked to lie very still on the CT table, which moves into the centre of the CT scanner. The scanner looks rather like a large donut. The ring of the CT machine contains the x-ray tube and other sensitive detectors. These are moved in a spiral motion around the head. The information from the scan is processed by a computer, then pictures are produced.
Your child’s head will be supported in a sponge cushion with soft straps to help maintain alignment. For some CT examinations, the radiologist will give your child an injection of a contrast dye to enhance some aspects of the images.
Is CT Safe?
The amount of radiation your child will receive from the CT Scanner is small, and less than in many other x-ray examinations. The risk of harm from the radiation your child receives is negligible.
Is CT painful or uncomfortable?
CT Scanning is a painless procedure.
Your child will need to lie very still on their back whilst the pictures are being taken. Foam cushions and Velcro straps are used around the forehead, shoulders and arms to help prevent movement. The CT Scanner makes a slight buzzing sound as it rotates. A recorded voice give instructions during the scan.
Can I be with my child during the CT Scan?
One parent may accompany the child during the CT scan, providing you wear a protective lead lined apron that is supplied by the department. If you have other young children with you, you will need to mind them in the waiting area. If your child requires a general anaesthetic to lay still for the procedure, you can remain with your child until they are asleep. This is so the anaesthetist, nurse and CT technologist can monitor your child closely.
If you are pregnant or suspect you may be, you should arrange for someone else to accompany your child in the CT scan room, as xrays are potentially harmful to the unborn baby.
Does my child need to fast?
If your child requires sedation or a general anaesthetic to lie still for the scan, specific instructions about fasting will be given to you by the medical imaging department. Children are usually fasted for 3-6 hours prior to the anaesthetic, depending on the child’s age, associated medical conditions, and the time of the scan. Antiepileptic medications should be taken with a small amount of clear fluid (less than 100ml water) close to the normal time. If you are uncertain about the specific instructions for your child, please contact the Department of Medical Imaging.
Where do I go and how long will it take?
CT scans for children are often done on an outpatient basis. CT is in the Department of Medical Imaging on the 2nd floor of the Royal Children’s Hospital. Signs to Medical Imaging (Radiology/Xray) are present at the Hospital entries, lifts and on the 2nd floor.
The time taken depends on the test. On average a head scan takes about 20 minutes. If your child has had an anaesthetic, he/she will be observed briefly in CT by the medical and nursing staff prior to leaving. Children under 12 months of age are occasionally admitted to the ward, for brief observation after a CT with anaesthetic or sedation. Otherwise, you will be able to leave immediately with your child following completion of the scan.
What if my child is sick or I am unable to keep the appointment?
If your child is sick and unlikely to tolerate or cooperate with the scanning, please contact the Department of Medical Imaging as soon as possible. This is particularly important if your child is to have a general anaesthetic.
When will I receive the result?
CT scans need to be printed from the computer and examined closely by a radiologist. Urgent, inpatient scans are analysed and reported on the same day. Non-urgent, outpatient CT scans are reported within 24 hours. Reports are sent to the requesting doctor, either by mail or fax. Patients of the Royal Children’s Hospital have their scans kept on file in the Hospital. CT scans of private patients are usually sent to the requesting doctor with the report.
Please note that the CT technologist cannot tell you the results of the scan when it is finished and secretarial staff will not give out results over the telephone. You must make arrangements with your doctor for receiving the result.
CT example images
The majority of children with epilepsy have normal brains and scans do not need to be performed. Furthermore, the majority of children with epilepsy who have scans are found to have no underlying brain abnormality. Nevertheless, brainscans done in selected patients may reveal specific abnormalities that are the cause of seizures.
 Right frontal cyst from head injury |
 Hydrocephalus from meningitis |
 Tuberous sclerosis |
 Left temporal tumour |
For more information
If you have questions about the CT scan, your appointment, anaesthesia etc. please contact the Medical Imaging Department on (03) 9345 5255.
If you have questions about the need for an CT scan or general anaesthesia, or questions about the results of the CT scan, please contact your doctor.