Back MRI: Things you must know

An MRI (magnetic resonance imaging) is a diagnostic modality based on the principles of magnetic field, radio waves and does not require any surgical incision. It helps doctors to view the soft tissues of the human body,...

Introduction

An MRI can be done for any part of the body, including the lumbar spine or the lower back. A back MRI or lumbar MRI specifically investigates the lumbar section of one’s spine. This is the region where back issues originate for people.

Understanding Lumbar Spine MRI

The lumbosacral spine comprises the five lumbar vertebrae (L1 to L5), along with the sacrum, which is the bony structure located at the base of the spine, and the coccyx, popularly known as the tailbone. Apart from this, the lumbosacral spine also includes major blood vessels, nerves, tendons, ligaments, and cartilage.

What is the purpose of an MRI of the lumbar spine?

The healthcare professional is likely to recommend an MRI for a better diagnosis or address problems with the spine. The condition could be triggered due to disease, injury-related pain, infection, or other factors. A doctor may order a lumbar MRI if a patient exhibits the following symptoms:

Continuous or acute lower back pain
Back pain along with fever
Birth defects implicating the spine
Any injury to the lower spine
Multiple sclerosis
Problems with the bladder
Signs of brain or spinal cancer
Weakness, numbness, or other leg-related problems, etc.

A lumbar spine MRI is also ordered when a patient is lined up for spinal surgery. This lumbar spine MRI will assist the doctors to plan the procedure of making an incision.

An MRI scan is superior to other imaging techniques like X-rays, CT scans, or ultrasound. The MRI of the lumbar spine helps the doctor to view the bones, spinal cord, disks, and also the spaces between the vertebral bones (the nerves through this space).

Risks associated with a lumbar MRI scan

Compared to other diagnostic methods like an X-ray or CT scan, an MRI is considered much safer because it doesn’t use ionizing radiation. It is a very safe alternative modality, particularly for pregnant women and growing children.

It may have some side effects, but they are very rare. There have been no recorded side effects due to the radio waves and magnetic fields generated during the scan.

However, people with metal implants do carry some risks while undergoing the scan. The use of magnets for the process may interfere with implants in the patient’s body like pacemakers and may cause implanted screws or pins to move inside the body. These are some of the perceived risks associated with the process.

Always talk to your physician about any metal implants beforehand. It is also worth mentioning that certain objects in the body might render the patient ineligible for the MRI. The doctor would be in the best position to address this issue. Hence, it is very important to discuss everything transparently before the process.

At times, the MRI scan may call for the use of a contrast dye to help in getting more clear visualization of the parts. Some patients may have allergic reactions to the contrast agent. A contrast dye is injected into the bloodstream of the patient, and the commonest contrast agent is gadolinium. Although the allergic reaction to the agent is mild and controllable with medication, at times it may be lethal too. So, it is important to be cautious while administering this contrast agent.

Getting ready for the back MRI

One should inform the doctor about any pacemaker. If a patient has a pacemaker implanted, he should inform the doctors beforehand. Depending on the type of pacemaker, the doctor may recommend alternative methods such as a CT scan.

However, it is also important to note that some pacemaker models can be reprogrammed to dodge any interference during the MRI.

Before the scan, the doctor will ask the patient to remove all jewelry and piercings and change into a hospital gown. MRI machines have magnets that can react with metals by attracting them. It's paramount to inform the physician about any metal implants or if a patient has items like artificial heart valves, clips, implants, pins, plates, prosthetic joints or limbs, screws, staples, or stents in the body.

One should discuss with the doctor any allergies or reactions. If the physician plans to use contrast dye during the MRI, ensure to inform them about any allergies or previous allergic reactions the patient may have experienced.

Talk about claustrophobia if you have any concerns regarding it. If a patient is claustrophobic and may feel uneasy during the MRI, he or she should inform the doctor in advance. Doctors usually prescribe anti-anxiety medications or, in some cases, provide sedation during the scan to people who are paranoid about confined spaces. If sedation is used, then, one should not drive back home. The patient should have somebody accompany him or her for the MRI scan so that the person can drive the patient back home after the scan.

Performing a lumbar spine

The MRI machine appears like a large cylindrical tube, which is a large magnet. The patient is required to lie down on the examination table which then slides into the machine. The whole process may take between 30 minutes to an hour.

If there is a need, the nurse or technician will inject a contrast dye through a tube intravenously. One may have to wait for up to one hour so that the contrast agent starts working.

The MRI technician will instruct the patient to lie on the bench, either on the back, side, or stomach. If there is any difficulty in lying down, the technician may provide a pillow or blanket for added comfort.

The technician operates the movement of the bench from an adjacent room and will be able to communicate constantly with the patient through a speaker installed in the MRI machine.

The MRI machine produces loud humming and thumping sounds while capturing images and the patients are provided with earplugs to help reduce the noise. Some treatment facilities may also have televisions or headphones with music to help the patient in passing the time and distract from the sounds.

As the images are being taken, the technician may ask the patient to hold their breath for a few seconds. This is to mitigate any potential motion artifacts that could impact the image quality. So, the patient should follow the technician's instructions throughout the process.

The patient won't feel any physical sensations during the back MRI procedure as it is a painless imaging process that is based on magnetic fields and radio waves to create detailed images, in this case, of the lumbar spine.

Conclusion

Some people worry about the cost of the lumbar spine MRI as it is a very sophisticated technique. The back MRI price is dependent on several factors. So, the patient should talk with the facility or the insurance company to get the actual cost of the process. Despite a high back MRI price, one has to go for it if advised by doctor for the sake of one’s health and well-being.