MRIs and CT scans are advanced medical imaging techniques that create detailed images of the internal structures of the body. These enable a wide range of diagnostics for conditions that can often not be diagnosed using traditional radiographic imaging techniques.
There are some important differences between the two methodologies, and the recommended method will depend on the condition being diagnosed and other factors.
We’ll delve into how MRI and CT scans work, what conditions they’re used to diagnose, and their differences and the advantages of each.
How Do MRI Scans Work?
MRI, or magnetic resonance imaging, is a noninvasive medical imaging technique that uses radio waves pulsed through a powerful magnetic field to produce detailed, high-quality images. Unlike most other radiological imaging methods, it uses no ionizing radiation, making it safer for patients who require a large number of views for diagnostics.
The patient is directed to lie on a table that slides into a cylindrical scanner that applies a strong magnetic field and pulses of radio waves from a scanner. The magnetic field temporarily realigns hydrogen atoms in the fat and water molecules found inside the body.
When the magnetic field is removed and the atoms return to their normal position, they emit varying amounts of energy that are detected by a scanner and sent to a sophisticated computer that creates high-quality images of the body’s internal structures.
How Do CT Scans Work?
A Computed Tomography scan, also called a CT or sometimes a CAT scan, is a highly sophisticated radiological imaging technique that uses ionizing electromagnetic radiation to create cross-sectional views of the body’s internal structures.
A patient is directed to lie on a table that slides into a large doughnut-shaped scanner. X-rays are emitted that rotate around the patient. This allows the scanners to capture multiple x-ray images from multiple different angles. It then uses advanced computer software to combine those images to produce cross-sectional views different from what you would see with other digital x-ray imaging.
These pictures can be viewed as individual slices or stacked to form a highly detailed 3D image. Since they use multiple views using ionizing radiation, they do expose patients to higher radiation doses than most other imaging methods.
What Do MRI and CT Scans Show?
Both MRI and CT scans show detailed views of different parts of your body. However, they do this differently, so naturally, the views they produce are different, making them useful in many distinct circumstances.
MRI scans typically produce more accurate, high-resolution images of soft tissues, making them invaluable for diagnosing issues with the brain, spinal cord, nerves, muscles, tendons, and ligaments. They are also used to detect breast cancer and other tumors, irregularities in blood vessels including aneurysms and artery blockages, brain abnormalities including multiple sclerosis, stroke, aneurysms and other conditions, inflammatory bowel diseases, and liver diseases.
They’re also useful for bone disorders because they show both the bones and the soft tissues around them, allowing doctors to see infections, inflammation, and tumors on or near the bones. Their high resolution enables early diagnostics of many conditions and plays an important role in monitoring the progression and treatment of diseases, especially in oncology, orthopedics, and neurology.
CT scans also produce detailed, high-quality images but are more used in emergency situations due to their speed. They are often used to identify bone fractures, internal bleeding, and tumors, especially in complex areas like the chest, pelvis, abdomen, and brain, where they provide clear views of soft tissues, blood vessels, and bones simultaneously for more rapid diagnostics.
Computed tomography scans are also used to diagnose heart disease, blood vessel blockages, kidney problems, pulmonary edema, and aortic aneurysms. They also help identify unknown masses in the liver, pancreas, or kidneys to determine whether or not they are cancerous. CAT scans can identify hemorrhaging, brain calcification, tumors, and blood flow problems in the brain.
They also help identify the causes of urinary bleeding and a wide range of lung conditions, including fibrosis, collapsed lungs, tumors, emphysema, pleural effusion, and more. It is also used when regular X-rays don’t provide a detailed enough view of more complex issues with the bones, including things like complex fractures, bone tumors, osteoporosis, and spinal cord injuries.
Finally, they are also widely used to assist in surgical, medical, or radiation treatment planning to help determine the safest and most effective methods for the patient.
What Can an MRI Detect That a CT Scan Cannot?
Even though both are powerful diagnostic techniques, there are some important differences between MRI and CT scans. MRI can produce sharper, more detailed results, especially of soft tissues and areas behind the bones, which can be hidden on CT scans.
What Are the Advantages of an MRI?
Magnetic resonance imaging, or MRI, has several advantages, especially its ability to produce highly detailed images of soft tissues that cannot be seen in regular radiographic imaging methods. Here are some of the main advantages that this technique offers.
- It is a non-invasive diagnostic technique.
- Instead of ionizing radiation, it uses a powerful magnetic field and computer software to produce images, making them safer than computed tomography for patients who require numerous views for diagnostics.
- Produce more detailed images, especially of the soft tissues, joints, organs, brain, and heart.
What Are the Advantages of a CT Scan?
Computed tomography or CT scans also have numerous advantages, especially in their ability to quickly produce detailed images, making them invaluable in emergencies. Here are some of their main advantages.
- They’re faster, allowing for more rapid diagnostics in emergency situations.
- Produce detailed, high-quality views at a lower cost than MRI scans.
- They can help identify issues in soft tissue like tumors, internal bleeding, as well as bone injuries and abnormalities.
- People with claustrophobia are less likely to have issues with computed tomography since the whole body doesn’t enter the scanner, unlike magnetic resonance imaging, where the entire body enters a tube that surrounds it, causing anxiety in some patients.
Frequently Asked Questions
Which Is Better, an MRI or CT Scan?
It depends on what you’re trying to diagnose. MRI is best for diagnostics requiring detailed views of issues with the spine, brain, nerves, muscles, and tendons and when trying to keep a patient’s radiation dose low. CT scans use ionizing radiation but produce much faster results, making them the preferred method in emergency situations.
Final Thoughts
MRI and CT scans are advanced medical imaging techniques that produce detailed views of the body’s internal structures. How they do that is very different, with MRI using magnetic fields and radiowaves while CT uses ionizing radiation. While both provide more detailed views of soft tissues than a traditional X-ray can, they take longer and typically cost more.
Contact our friendly staff at Maven Imaging today if you have any questions or are interested in our quality digital X-ray machines.
