CT Scan vs. MRI: What’s the Difference?

Understanding the difference between CT scans and MRIs is crucial for informed healthcare decisions. Throughout this article, we'll outline the differences between these imaging techniques so you can make an informed decision about your medical care.

The Difference Between a CT Scan and an MRI

A CT scan uses X-rays to create cross-sectional images of the body's internal structures. On the other hand, an MRI uses strong magnetic fields and radio waves to generate images without ionizing radiation.

In short, a CT Scan uses radiation, and an MRI does not.

CT Scan

Computed tomography, or CT scans, is a series of rapid X-rays that create clear images of bones, organs, and other tissues.

A patient lies on a table that moves through a scanning ring. A series of images are obtained, and a computer assembles these slices to create a 3-D picture of the area of the body imaged. A CT scan is typically a fast test conducted over a few minutes.

Doctors often use CT scans to detect common ailments, such as: 

• Bowel problems such as appendicitis, diverticulitis, or bowel obstruction
• Blood clots
• Tumors
• Broken or fractured bones
• Trauma-related injuries
• Head injuries resulting in bleeding in the brain or skull fractures

MRI: Magnetic Resonance Imaging

The process for patients is similar because this tool also creates detailed pictures of areas inside the body. MRI is a painless test in which the machine obtains detailed images of a specific area of the body.

However, an MRI uses radio waves and a powerful magnet to generate the pictures. 

MRI often takes more time than a CT scan. MRI does not expose the patient to radiation. Like CT, MRI can be used to image almost any area of the body. MRI is commonly used to obtain clear pictures of the brain, spine, spinal cord, and joints.

While CT gets a great look at the bones, MRI is better for imaging soft tissues such as nerves, spinal cord and discs, and the ligaments and tendons.  

For example, a knee CT scan will give a great look at the bones to evaluate for a fracture, but an MRI will show damage to the soft tissue, such as ligaments and cartilage, such as the meniscus.

MRI of the brain is also commonly used to evaluate strokes and other neurologic disorders.

CT Scan vs X-Ray

Since a CT scan uses X-ray pictures, how is it different from an X-ray machine? 

While they use similar technology, the main difference between CT scans and X-rays is the detail each can provide. CT scans create detailed, three-dimensional images, while X-rays produce two-dimensional images. 

CT scans are more detailed because they take multiple pictures at different angles and combine them to create a 3D image. This can provide more information than a 2D X-ray image.

Can You Have a CT Scan and an MRI the Same Day?

Yes, having a CT scan and an MRI the same day is perfectly safe. 

If you have any specific concerns, discuss them with your healthcare provider.  

Why Do I Need a CT Scan After an MRI?

Sometimes, a physician may order a CT scan after an MRI. This is because both are effective diagnostic tools but excel in different areas. 

The reasons to use one type of imaging or another are complex and depend on the disease process being evaluated. 

Does The Urgency Room Have an MRI Machine?

No, we do not have an MRI machine. Our state-of-the-art facilities are equipped with advanced diagnostic equipment to meet the needs of our patients, including CT scanners, X-rays, ultrasounds, sedation capabilities, and a high-complexity lab.

Patients seeking an MRI scan should wait to start care at The Urgency Room. 

Visit The Urgency Room for Quality Care

Whether you need a CT scan, The Urgency Room can help you achieve a diagnosis and develop a treatment plan. Schedule an appointment at one of our locations to get the process started.