- MRIs and X-rays are commonly used to create images of internal structures of the body.
- There are several differences between an MRI vs. X-ray, including technology used, how images appear, price, and risks.
- While X-ray technology has been around longer, MRI scans are becoming more available and helpful–especially when it comes to cancer screening.
MRI vs. X-ray: It’s common to wonder which type of imaging you should choose. Thankfully, you don’t need to make this decision on your own.
Your healthcare team will help you decide the right imaging for you, give you other medical advice, and help you create an imaging plan together. However, we’ll also arm you with information about what makes one diagnostic imaging option different from the other.
Let’s start with what MRIs and X-rays have in common. Magnetic resonance imaging (MRI) and radiography (X-rays) are two of the most commonly used imaging technologies.
They can both help radiologists spot abnormalities in the body without making a single incision. This helps medical practitioners evaluate, diagnose, and screen for various medical concerns.
MRI vs. X-Ray: How Do They Work?
An X-ray (or radiography) uses ionizing radiation to create images of body structures. X-ray technology is the oldest form of medical imaging and is the most commonly used form thanks to its convenience and affordability. X-rays are quick and painless, usually taking only a few minutes to complete.
Rather than using radiation, MRI machines use magnetic fields and radio waves (as well as a computer) to create an image of your body’s internal structures.
The powerful magnet used during an MRI sends radio waves through the body to create detailed images of the body. When the radio wave passes through the body, tiny proton atoms inside your body react and create the picture.
During an MRI, energy is passed through a coiled wire to create a temporary magnetic field around a certain part of the body. MRIs can take 20-90 minutes depending on the area being imaged.
The price of an MRI can vary widely depending on the area of the body being evaluated as well as the type of facility and where you live.
According to Business Insider, MRIs can range from a few hundred dollars to several thousand while X-rays can be as inexpensive as $40.
MRI vs. X-Ray: Why Are They Used?
X-rays are most often used to diagnose fractured bones, evaluate for injury or infection such as pneumonia, and locate foreign objects in soft tissue (like metal or wood from trauma). You may also need an X-ray if there is a concern about a dislocated or misaligned joint.
X-rays can’t show soft tissue or inflammation very well. This is where the more advanced MRI technology can help.
MRIs can evaluate soft tissue (including internal organs), nerves, and blood vessels. Because of this, MRIs are helpful when evaluating and screening for cancer. Joint health can be closely evaluated with MRI imaging as well including:
- Cartilage loss
- Joint inflammation
- Spinal injury
- Torn or detached ligaments and tendons
MRIs can differentiate between fat, water, soft tissue, and muscle much better than an X-ray or even a CT scan.
Risks of Getting an X-Ray
X-rays send radiation waves through your body to generate black and white images. The radiation used during an X-ray is considered ionizing radiation, which means it can remove electrons from atoms and molecules (including human tissue and organs).
Even though X-ray machines use only very low doses of this high-energy radiation, exposure to this type of energy means a slight risk increase for developing cancer later in life. Skin changes including redness or hair loss can also occur with ionizing radiation exposure.
According to the FDA, women who are pregnant should avoid X-rays that involve areas around the lower torso, including the pelvis, abdomen, and lower back.
The evidence is conflicting when it comes to how an X-ray could affect a fetus, but some experts say there is a concern for birth effects or certain childhood cancers if the fetus is exposed to ionizing radiation.
However, according to the American College of Radiology, MRI scans have no proven risk to pregnant women or their unborn baby.
The decision to have an X-ray is one to be made together with your provider. Most of the time, X-ray images can be created with minimal risk.
However, since the risk isn’t zero, X-ray imaging should only be done if completely necessary and when no other imaging options are available.
Risks and Precautions When Getting an MRI
Although MRIs do not use ionizing radiation like X-rays, there are a few risks to be aware of. The biggest risk comes from the generation of a strong magnetic field from the MRI machine. Anything magnetic objects nearby (anything made of metal) may become attracted to the magnetic field.
This attraction can be very strong, causing metal objects to become projectiles. This is why it’s extremely important to never wear or bring anything metal into the MRI suite during a scan. This includes jewelry, cell phones, belt buckles, and keys.
Magnetic objects also include certain implantable devices such as pacemakers, artificial joints, and stents. The radio waves used during an MRI can alter how well these devices work and potentially cause the device to move. Another risk is the medical device warming up and causing burns due to the magnetic force.
Patients who suffer from claustrophobia sometimes take prescription medication to help lower anxiety prior to an MRI, as the MRI scanner can feel confining.
You may hear a loud repetitive noise heard during an MRI, so wearing ear protection (or MRI-safe headphones to listen to music) can help prevent any risk for hearing loss.
MRIs can take over an hour to complete and require the patient to be completely still. This can be painful if the patient is already in pain due to an injury.
MRI vs. X-Ray: Which Test Is Right for You?
When it comparing an MRI vs. X-ray, there are several things to consider. These imaging tests differ in how they work and what they’re commonly used for.
X-rays are fast and inexpensive. However, because they carry the risk of ionizing radiation exposure, they should only be used when needed. This risk is also why X-rays aren’t typically recommended for routine cancer screening.
MRIs create a much higher quality image compared to X-rays. They’re an overall safe way to routinely screen for cancer and other internal concerns.
While there are risks associated with MRI, very few adverse MRI events are reported to the FDA.
At ezra, we do our best to address many of the common concerns associated with MRI scans. Our MRI technology is four times faster than a typical MRI scan, and our full-body MRI takes only an hour to complete.