MRI scans use a very powerful magnetic field combined with RF (radiofrequency) signals to produce an image of the internal structures of your body. When we alter the magnetic field or radiofrequency signals, we can acquire different types of pictures to focus on different tissues in your body.

It occasionally requires an intravenous injection of contrast medium into a vein, usually at your elbow or back of the hand.

MRI scans are excellent at imaging soft tissue structures of the human body such as ligaments, tendons and cartilage in great detail. It creates an image of the brain and spinal cord that has more clarity than CT or X-Rays, and can also be used to assess parts of the vascular system with or without an injection of a contrast dye.

MRI scans are very safe with the right precautions. The scan only utilizes the radiofrequency waves similar to radio waves from a tower. This is not ionizing radiation like X-Rays or gamma rays, so it does no damage to cellular DNA.

The MRI is very powerful – our scanners have a field strength of 3 Tesla which is approximately 60,000 times the strength of the Earth’s magnetic field. If you imagine how a paperclip sticks against a refrigerator magnet, this could happen to any ferromagnetic item in the MRI scanner with more serious consequences. If the metal is inside the patient, it could attract to the magnet or twist, causing discomfort or even injuring the patient if the metal is outside the body.

Aside from the magnetic field, the radiofrequency waves can have an effect on other metals on or inside your body even if they are not ferromagnetic. Radiofrequency waves deposit energy in the form of heat which is usually distributed evenly across the body; when metal is introduced to the environment, this can concentrate the energy and cause a radiofrequency burn.

It doesn’t matter if we scan your head and the object is in your foot; if a metallic object is located even three metres away from the scanner, it can be affected by the scanner.

Please let us know if any of the following points apply to you:

• If you have any metal implants of any kind, such as heart pacemaker, neurostimulator, metal pins, medication pump, or/and joint replacements.
• If you have worked with metal.
• If you have poor renal function.
• If you are claustrophobic.
• If you have had any reaction to a contrast injection given for a previous MRI scan.

We will need you complete a questionnaire before the examination, and sign a consent form to the contrast injection if it is required for your examination.

Most MRI scans require very little preparation. Before your appointment time we require several forms to be filled out. There is an MRI screening form to ensure you have no implants or foreign bodies inside of you which may be unsafe in the scanner.

We require all metallic objects anywhere on your body to be removed, including piercings and jewellery. You may be asked to get changed into a gown, depending on what type of clothing you are wearing; burns have even been known to occur with invisible silver embedded in sports clothing (Pietryga et al. 2013).

If you have any metallic implant inside your body, you must notify staff at the time of booking. Our receptionists and technicians are trained to identify and verify implants for MRI safety, and will only proceed with the MRI scan if the suspect foreign body has been identified. If a foreign body cannot be identified, we may decline to scan in order to protect your health and safety.

For some abdominal, pelvic or vascular scans we require patients to fast, drink water, or attend their appointment early for preparation. Please speak to our friendly reception staff for further information.

Please bring any previous films with you for comparison.

Our Radiographers will first confirm that you have no metallic objects on your person OR inside of yourself. If there is any concern, we may abort the scan due to safety reasons.

The scanning process is very loud, so our staff will provide hearing protection for you to avoid any hearing damage. We can also play music through specially-made headphones to help alleviate any distress during the procedure.

The Radiographer will then lie you down inside the machine and may place some equipment on the region of interest. Different body parts require different pieces of equipment to acquire an image.

We will then move you into the machine and begin the scan. The scanner will make a variety of different noises that will last from a couple of seconds up to ten minutes at a time. Depending on the region being examined, procedures times can range from 10 minutes up to 1 hour.

A MRI Scan can take from 10mins to 1 hour in total depending on the nature of the investigation.

Our scanner at High Street Medical imaging is a wide-bore scanner, meaning that the space the patient lies inside is very large – 70cm in diameter. It is also one of the shortest scanners on the market, meaning that a patient’s head will be outside of the scanner for any scan from the knee down.

For patients with severe claustrophobia, we highly recommend that a friend or family member attend to support them. We can allow one family member in the scan room during the scan to hold the patient’s leg or hand to provide support; as with the patient, they will also require screening to ensure they have no metallic implants in their body.

Allergic reactions to contrast material can occur but significant reactions are rare, and generally respond to adrenalin. Our staff members are equipped and trained to treat contrast reactions. Some scans create a slight sensation of heating. There are no adverse effects from the magnetic field or radio waves used to generate the images.

There are no known side effects from undergoing MRI. The MRI scan is a non-invasive, painless and safe procedure that doesn’t require any ‘recovery time’. There are no special after-care instructions.

The MRI scan is a very safe procedure. Occasional complications may include:

• Metal objects (such as jewellery) worn during the scan can cause injury.
• The powerful magnetic field of the MRI scanner may damage internal metal devices, such as a heart pacemaker.
• In some cases, such as in the investigation of blood vessels, a contrast dye is injected into a vein immediately prior to the scan. This helps to produce a clearer picture. Rarely, a patient may have an allergic reaction to the contrast dye.

It is important that you make an appointment to return to your doctor after you have collected your examination result. Whether they are normal or abnormal, your doctor needs to correlate with other information for further management.

Your result will include a copy of the images from your study as well as a report from our radiologist.

Depending on your referrer’s preference(s), a copy of the report can also be sent to your referring doctor by fax or electronic download.

Digital copies of all studies are stored on our secured database for comparison with any future examinations.

If your examination requires fasting, then book an early morning appointment and have your breakfast and diabetic medication after the examination.

If your examination will require an intravenous injection of contrast medium, we need to know your renal function. Please bring along the results of your most recent blood test with your creatinine and GFR level.