Dorsal spine MRI

A person may not be scanned under the following conditions unless evaluated for safety:

• If they’re pregnant, especially in the first trimester
• If they have body piercings or permanent tattoos
• If they wear a medication patch
• If they have medical implants such as:
  • Cochlear (ear) implants
  • Implantable pumps, such as an insulin pump
  • Pacemakers
  • Cardiac defibrillators
  • Metal coils placed within blood vessels
  • Aneurysm clips
  • Metal pins, screws, plates or surgical staples
• If they have metal fragments or bullet wounds

The doctor may order a dorsal MRI to detect or assess the following conditions:

• Birth defects of the spinal cord 
• Trauma or injury to the spine or spinal cord
• Compression or inflammation of spinal cord and nerves
• Infection of the spinal cord or spine
• Tumours in the spinal cord, spine, nerves or surrounding soft tissue
• Disc or joint disease

The test is performed to monitor any changes after a spine operation, such as scarring or infection. The doctor may order this test to plan spine surgeries such as decompression of a pinched nerve. MRI scans can be ordered before giving steroid injections during the surgery. The test may also be ordered to detect possible causes of long-term back pain.

You can eat, take your medications and drink as per your usual routine before the test unless instructed otherwise. You may be asked to wear loose clothes or change into a hospital gown for the test. Remove all jewellery and other accessories before the test. Metal and electronic items can cause burns during an MRI scan; hence, you should avoid bringing such items into the scanning room. You will be asked to fill a consent form to ensure that you do not have any metal items in your body.

Your doctor may give you medication for anxiety if you have a fear of small, enclosed areas. You must notify the doctor if you are pregnant and also about any recent surgeries, serious health problems or allergic reactions to the contrast dye.

(Read more: Spinal cord injury)

If an MRI with contrast is planned, an intravenous line will be started in the arm to inject the dye. The following procedure is then performed:

• The technician will ask you to lie on the scan table. Straps and pillows may be used to help you remain still during the procedure.
• A headset or earplugs will be provided to help block the noise from the scanner. 
• The scan table will slide into the large opening of the scanning machine.
• The scanner is controlled by the technologist from another room, but they will be watching you at all times and can hear you and communicate with you through speakers inside the scanner.
• You can press a call button and inform the technologist if you have any difficulty during the procedure.
• During the scan, clicking noises will be heard as a magnetic field is produced and the scanner sends pulses of radio waves.
• At intervals, the technologist may request you to hold your breath for a few seconds. 
• After the scan, the technologist will slide the table out of the scanner and help you off it.

The complete MRI procedure may take 30 minutes to two hours.

(Read more: Spine fracture)

MRI scan causes no pain. However, you may experience mild discomfort since you will be asked to lie still until the procedure is complete. During the test, you may hear different intermittent sounds from the scanner, such as humming, clicking and knocking.

When a contrast dye is injected, you may experience a flushing sensation, a feeling of coldness, itching, nausea, vomiting, metallic taste or a brief headache. These symptoms will disappear after some time on their own.

Some conditions that can be detected with the help of a dorsal spine MRI are:

• Spinal cord compression
• Syringomyelia (a cyst with fluid in the spinal cord)
• Tumours of the spine
• Herniated disc
• Multiple sclerosis
• Myelomeningocele (a birth defect in which the bones of the spine are not completely formed)
• Enlarged lymph nodes near the spine
• Degenerative lesions of the spinal cord

(Read more: Spina Bifida)

The benefits of an MRI are:

• MRI is a non-invasive test with no exposure to radiation.
• The images are detailed and clearer than those from other imaging procedures.
• It uses gadolinium dye which is less likely to cause an allergic reaction compared to iodine dye used in an X-ray and CT scan.
• Sometimes, certain abnormalities are obscured by bone in imaging methods; in such cases, MRIs can be used to detect them.

The risks of an MRI are:

• Although the magnetic field is not harmful, it can cause malfunctioning of implanted medical devices or distortion of the images.
• There may be an allergic reaction from the contrast dye.

(Read more: Spine MRI)

There is no specific care required after the test. You can resume your usual diet and perform your daily activities. However, if a contrast dye is injected, you will be monitored for any side effects of the dye such as itching, difficulty in breathing, swelling or rashes. Inform your doctor if you notice pain or swelling at the site of injection. Avoid driving if you are given sedatives or anti-anxiety medication before the test.

Other tests that may be performed with the MRI to diagnose spine conditions include:

• Nerve conduction velocity
• Electromyography
• PET scan
• Biopsy
• CT scan

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.