Magnetic Resonance Imaging (MRI) makes use of magnetic fields and radio waves to examine internal structures of the body in any number of planes. The procedure is non-invasive and completely harmless. No ionising radiation (such as X-rays) or radio-active material are utilised during the study. MRI is particularly useful for imaging soft tissue such as the brain. As well as allowing tissue structure to be visualised in every high detail, it is also capable of measuring certain characteristics of brain function.
The powerful magnetic field necessitates several safety measures: if you wear a pacemaker, infusion pump, certain metallic clips, heart valves or orthopaedic prosthesis, these must be brought to the attention of the radiographer. Before the examination, all metal objects including credit cards and watches must be removed.
What can I expect during a scan/examination?
The procedure requires that you lie on your back with your head in a "tunnel" which is very similar to a CAT scan machine. The tunnel is open on both sides and is well lit and ventilated. You will at all times be in intercom contact with the radiographer, who will also be able to see you at all times.
The examination will take about 45 minutes and will be accompanied by a series of loud knocking sounds. There are no moving parts within the scanner, and the knocking sounds occur due to vibration of the machine in the magnetic fields. In some instances, the intravenous administration of contrast agent is also necessary, but you will be notified in advance about this. Finally, it is important that you do not move at any stage during the examination as this makes the images blurry.
Can patients with hip replacements be scanned?
Q: I have an elderly lady who had a hip replacement two years ago. I am yet to find out where it was done and what the materials are, but just wanted to know if this is already a no for a scan before I investigate any further?
A: Hip replacements are fine, provided the prostheses are made of non-ferromagnetic material such as aluminium or titanium and the scan is done 6 weeks after insertion. The list of safe materials also includes copper and platinum. Stainless steel implants are not safe for scanning.
Please visit: MRIsafety.com and go to “The List” for more information regarding implants.
Can breastfeeding patients be scanned?
Q: I was wondering what the policy is on scanning someone who is breastfeeding. I know we’re always checking whether people are pregnant or breastfeeding. Does the latter pose a problem for being scanned, and if so, why is that (just for my own understanding)?
A: Breastfeeding shouldn't be a problem as long as you are not giving contrast. You could advise participants to express before the scan to avoid discomfort during the scan.
Can patients view the scanner/facility before booking their scan?
Q: We have a participant lined up that is very keen to take part in our study, but she has severe claustrophobia. Is it possible to bring her in for a brief visit first, so she can see the machine and perhaps even quickly experience being on the bed, before we book a proper scan with her?
A: Yes, it is possible to show the patient what the scanner looks like before coming for the actual scan. It may not always be possible to do a “test-run”, due to our busy schedule. Please note that the patient will have to lie in the scanner for at least an hour with a head-coil positioned over the face and may not be able to tolerate the closeness of the coil. Therefore, we do not advise recruitment of claustrophobic participants.
How do I access my data?
In order to access your data on the CUBIC server you will need an active UCT staff/student number.
If you are currently not employed by or studying at UCT, you can obtain a temporary (a 3rd party) UCT number by completing the BAS03 form and returning it to email@example.com
Within a day or so we will supply you with a temporary UCT staff number.