Computed tomography (CT) and magnetic resonance imaging (MRI) are both used for essentially the same thing: to diagnose cancer. However, what many people don’t know is the difference between the two methods or why you should choose one over the other. But we, here at Intermountain Medical Imaging, are here to help.
What are MRIs?
Using a large magnet, radio waves, and a computer, MRI scans create a detailed, cross-sectional image of your internal organs and structures.
Inside the machine, a constant magnetic field and radio frequencies are bouncing off of the fat and water molecules in your body. These radio waves are then transmitted to a receiver inside the machine, which uses it to translate an image of the body that can be used to diagnose various issues.
The following are examples where an MRI would be needed:
- Anomalies of the brain or spinal cord
- Tumors, cysts, and more in various areas of the body
- Breast cancer screenings for women who might have breast cancer
- Injuries or abnormalities of the joints
- Various types of heart problems
- Liver and other abdominal organ diseases
- Pelvic pain evaluation in women
- Uterine anomaly detection in women undergoing evaluation for infertility.
What are CT scans?
A CT scanner emits a series of narrow beams throughout the human body as it moves in the path of an arc. Its X-ray detector can see hundreds of complex levels of density, including tissues within a solid organ. This data is then transmitted to a computer, which uses it to build a 3-D cross-sectional picture of the body.
CT scans are often the preferred way of diagnosing many types of cancer. The following are some other examples of when CT scans are used:
- Confirming the presence and location of a tumor, its size, and how much it has affected the nearby tissue.
- Scanning the head to give crucial information about the brain such as if there’s any bleeding, swelling of the arteries, or a tumor.
- Revealing lacerations of the spleen, kidneys, or liver.
- Detecting abnormal tissue.
- Deciding the areas for radiotherapy and biopsies as it can provide tons of valuable data on blood flow and other vascular conditions.
- Assessing bone diseases, bone density, and the state of the patient’s spine.
- Providing vital data about injuries to a patient’s hands, feet, and other skeletal structures.
- Seeing small bones clearly, as well as their surrounding tissue.
The main differences between CT scans and MRIs are:
- While a CT scan uses X-rays, an MRI uses magnets and radio waves
- A CT scan doesn’t show tendons and ligaments while an MRI does
- MRI is better when dealing with the spinal cord
- A CT scan is better for cancer, pneumonia, abnormal chest x-rays, and bleeding in the brain
- Detecting a brain tumor is easier with an MRI
- A CT scan is better suited for trauma cases
- Broken bones are more clearly visible on a CT scan
- CT scans give a better image of the lungs and organs in the chest cavity between them.