MRI stands for Magnetic Resonance Imaging. An MRI scanner allows radiologists to view detailed images in cross-section of certain areas in the body without using interventional techniques or ionising radiation (x-rays). The MRI scanner uses a combination of a strong magnetic field, radio frequency waves and computer technology to produce very clear images of human anatomy and to detect areas of abnormality. The clarity of anatomical detail on MRI imaging is superior to other scanning methods.
No, due to the strong magnetic field, metallic objects cannot be taken into the scanning room which includes certain implants.
For example, if you have a cardiac pacemaker, you should not have an MRI. There may be certain parts in the pacemaker that may be adversely affected by the magnetic field of the MRI scanner, causing the apparatus to malfunction or cease operating.
Other problems:
Aneurysm clips. These are metallic clips that have been surgically clipped around a bleeding vessel. Some aneurysm clips are MRI safe; some are not. You need to check with the surgeon who installed the clips to be sure the manufacturer has tested it and found it to be MRI safe before booking your MRI.
Other conditions that need to be investigated before an MRI scan can be safely undertaken are:
- Neurostimulators
- Metal heart valves
- Metal Implants
- Drug Infusion Devices/Pump
- Ear Implants
- Inferior Vena Cava filter
- Metal Objects in Eyes
- Surgical Staples or Wires
- Bone or Joint Replacements
- Metal Plates, Rods, Pins or Screws
- Penile Implants
- Shrapnel
- Pregnancy
- Vascular Coils and Filters
If any of the above applies to you, be sure to make the staff at the Centre aware well in advance especially when they phone you to make the appointment. You should also tell the doctor who is referring you for the scan, as they will be able to tell you if it is safe for you to have the MRI scan. In most cases you will be able to have the scan, but the decision to go ahead will be made by our clinical staff. On arrival at the MRI Centre you will be asked to complete an MRI Safety Questionnaire which will cover all of the above. – Note: Anyone accompanying the patient into the MRI scanning room is subject to the same issues and will have to complete a Safety Questionnaire first.
Preparing for an MRI exam is easy. Unless your doctor tells you otherwise, please take your medications as usual.
There are no food or drink restrictions.
The only unusual preparation for an MRI scan is that all removable metallic objects must be left outside the scanning room. These include jewellery, keys, watches, coins, eyeglasses, removable hearing aids, dentures and prosthetic devices.
Credit cards should not be brought anywhere near the MRI magnet. Since they are magnetically coded, the MRI’s magnet, which is very powerful, can easily corrupt the information stored on them.
There is no pain associated with having an MRI scan. Unlike many other MRI scanners, ours are comfortable and non-claustrophobic. They are also much quieter than ‘tunnel’ MRI scanners.
Our scanner is an Open MRI and very patient friendly. There are no tunnels or tubes to go into. Our scanner is comfortable, non-claustrophobic and you can even watch television during your scan. We specialize in scanning claustrophobic patients, and our staff will do their utmost to make you feel at ease.
When it comes to how to dress for an MRI exam, the main thing to realize is that metal can degrade or ruin MRI pictures. Therefore, you should wear comfortable, loose fitting clothing (no dresses or skirts for modesty reasons), but keep in mind that metal must be avoided in or near the region where you are going to be scanned. Here are some examples:
If you are going to have a scan of the lower spine (lumbar spine) or the abdomen area, don't wear clothing or under-clothing that has metal on it in that area. For example, a body suit that has snaps in the crotch, or pants with fasteners or a zipper will cause a problem. Sweats with no eyelets would be fine. Also, body-pierced jewelry in that region must be removed.
If you are having a scan in the head or neck area, remove all makeup (some makeup has metallic particles in it) and all metallic items such as hair clips, earrings, and facial jewelry, including body-pierced items. Notify the technologist if you have any facial tattoos, such as eyeliner or eyebrow tattoos.
If you are having a scan in the chest area, or upper torso, avoid clothing and under-clothing with metal hooks or fasteners. For example, a sweatshirt with metallic decorations or body-pierced jewelry in that region will cause a problem
Don't worry. If you don't have suitable clothing, we will give you a gown.
If you are pregnant or think you might be pregnant, you must first consult with the physician before you have an MRI scan. You must also inform the staff at the MRI scanning center.
It has not been shown that MRI is harmful to unborn children. However, if you choose to have the MRI, you will be asked to sign a consent form, which must also be signed by your OBGYN.