Spine MRI

Since the MRI creates a strong magnetic field, it is usually avoided in the following people unless evaluated for safety:

• Pregnant women, particularly in the first trimester
• People with certain metal implants, such as:
• Ear implants
• Pacemakers or cardiac defibrillators
• Metal coils placed in blood vessels 
• Clips used for brain aneurysms
• People with any metal embedded in the body, such as bullets or shrapnel
• People with tattoos, as some tattoo inks contain iron that can heat up during the scan

The doctor may order a spine MRI if you have back pain with accompanying signs or symptoms such as:

• Difficulty with walking and balance
• Recent serious fall or injury
• Worsening numbness or weakness in a leg
• Severe back pain that isn’t relieved by pain medications
• Inability to pass urine or stool
• Inability to control urine or stools
• Fever
• History of cancer

The spine MRI helps the doctor detect injuries, abnormalities, tumours and other conditions of the spine and the surrounding tissues.

The spine MRI also helps the doctor to plan procedures, such as:

• Decompression of a pinched nerve
• Administration of steroid injections
• Spinal fusion

Unless instructed otherwise, you may eat and drink as usual. If you have a fear of closed spaces, the doctor may give you a mild sedative before the test. Inform the radiology staff and your doctor if you are pregnant or nursing.

You must leave all metallic and electronic items outside the examination room, as they can interfere with the procedure. These include:

• Jewellery, watches and credit cards
• Hairpins/metal zips and other metal objects
• Removable dental work
• Body piercings
• Phones and other electronic devices
• Pens, pocket knives and eyeglasses

(Read more: Spine fracture)

The part of the spine that is scanned will depend on the location of your symptoms. The MRI will be done in the following steps:

• You will be given a hospital gown to wear during the procedure.
• If a contrast dye is used, it will be given through a vein in your arm. A contrast agent enhances the clarity of the images in some cases.
• You will then lie down on the table that slides into the large cylinder-shaped opening of the scanning machine.
• The technologist will operate the machine from another room but will be able to see you and communicate with you at all times.
• You must remain very still during the scan, as movements can blur the images.
• After the scan, the table will slide out of the machine, and the technologist will help you off the table. If an intravenous line has been used for administering contrast media, it will be removed.
• The entire test is usually completed within an hour.

(Read more: Lab tests)

The scanning procedure is painless, but lying still for a long duration of time may make you feel slightly uncomfortable. While the scanning machine makes loud tapping and thumping sounds, you will be provided with earplugs to block out the noise.

When the contrast agent is administered, you may experience brief side effects such as:

• Flushing sensation 
• Salty or metallic taste in the mouth
• Itching
• Nausea or vomiting
• Headache

The spine MRI can detect conditions such as:

• Injury to the vertebrae and surrounding soft tissues
• Injury to the spinal cord
• Structural defects in the spine or spinal cord
• Disc and joint diseases
• Compression or inflammation of the spinal cord and nerves
• Infection of the spine, discs or spinal cord
• Tumours of the spinal cord, vertebrae or surrounding soft tissues
• Broken vertebrae (compression fracture) and bone swelling
• Scarring or infection in the spine after surgery
• Long-term diseases of the central nervous system, such as multiple sclerosis

The benefits of the spine MRI are:

• Non-invasive
• No exposure to radiation
• Best imaging test available to view the spinal cord and nerves
• Shows spinal injuries, abnormalities and diseases that may not be seen with other imaging methods
• Can detect early signs of an infection or tumour

The risks involved with the spine MRI are:

• The magnetic field may cause malfunction of implanted medical devices.
• The contrast agent may cause harm to people with serious kidney diseases.
• An allergic reaction to the contrast agent may occur in rare cases.

You may continue with your routine diet and activities after a spine MRI unless advised otherwise.

If a contrast agent was used, then you will need to be monitored for some time for any allergic reactions such as swelling, rashes, itching or breathing difficulty.

If a sedative was given, you will be asked to rest and to avoid driving until its effects wear off.

If you notice signs of infection at the site of injection, such as redness or swelling, inform the doctor.

Other tests that may be done with a spine MRI include:

• Computed tomography (CT) scan 
• Magnetic resonance angiography (MRA)
• Myelogram 
• Spinal tap
• Discography

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.