What is an MRI scan?
MRI (Magnetic Resonance Imaging) works in a completely different way to CT scans. It does not involve X-rays so avoids the very small risk of radiation, but uses a strong magnetic field. This gains detailed information at an atomic level, which is then reconstructed, using a computer, into images of the internal organs. In certain circumstances, MRI can produce superior information compared to CT such as imaging the small bowel, rectum and anal fistulae. It can also be used to clarify abnormalities seen on CT such as in the liver.
The images will be viewed and reported by an expert radiologist who specialises in the field. The report is sent to your surgeon who will discuss the findings with you in the clinic.
Do I need any preparation for an MRI scan?
The radiology department that performs the scan will be in touch to make an appointment. As strong magnets are used for this scan, you will ask various questions including:
- Do you have metal implants such as joint replacements or vascular stents?
- Do you have a pacemaker?
- Are you pregnant?
The radiology department will send out information to you and do contact them if you have any questions.
Once you are in the scanning room, you will be asked to lie down in the tube of the scanner. Some patients may find this claustrophobic. If you suffer from this in anyway do get in touch beforehand so we can minimise any fears or discomfort. All you need to do is lie still during the scan and as for a CT scan, you may require a cannula for contrast dye injection into a vein. To ensure the best images the scans can take a while to perform, up to an hour. Following your scan, you can go home and should be safe to drive yourself.