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

Published: 12:24 pm, Thu July 11, 2024

How We Recommend Preparing For Joint Replacement Surgery
Has your doctor just recommended an imaging test, and you’re curious about the difference between an MRI (magnetic resonance imaging) and a CT (computerized tomography) scan? When it comes to imaging tests, CT scans and MRIs are two of the most powerful diagnostic tools in a doctor's arsenal. But what's the difference between these seemingly similar scans? In this post, we’ll show you the differences, advantages, risks, and which imaging technique best suits your needs!

What Is the Main Difference Between an MRI and a CT Scan?

MRI and CT scans are imaging tests that help view certain structures inside your body. A CT scan works like an X-ray machine but takes more detailed pictures. An MRI scan uses magnets and radio waves to take even more detailed images within your body. Both scans involve lying on a table that moves through a big, donut-shaped machine. The doctor will decide which scan you need based on what they're looking for. Here's the main difference between the two: CT scans use X-rays, while MRI scans use magnets and radio waves. This means that MRI scans can create more detailed images of your body, but they can also take longer and be more expensive. A CT scan is faster than an MRI. It usually takes about a minute to get done, while an MRI can take between 30 minutes to an hour. Ultimately, the best scan for you will depend on your specific situation and what your doctor recommends because certain circumstances may favor one over the other.

Benefits of CT Scans and MRI Scans

CT scans are generally better at spatial resolution, which is how clear and detailed an image is when it comes to small features. MRI scans, on the other hand, are better at contrast resolution, which is how well the system can distinguish between different shades or brightness levels within the image. So, each scan is best at detecting certain problems in the body. CT scans are great for spotting where cancer has spread, making them super helpful in figuring out cancer stages. Plus, they’re also really good at detecting detect kidney stones. Other things CT scans will diagnose are issues with:
  • Bones
  • Blood
  • Lungs
  • Blood
  • Abdomen
man ready for a CT scan An MRI uses magnetic waves to produce clear and detailed images and is great for showing tiny differences between tissues that might look similar in other types of scans. This helps doctors make an accurate diagnosis and a treatment plan that works for you. So, MRIs are really good for diagnosing inflammation and detecting cancers like some liver cancers, uterine cancer, and prostate cancer. MRIs are good for:
  • diagnosing brain and nerve tissues.
  • providing greater details of joints, ligaments, tendons, and soft tissues of the bones, 
  • providing highly detailed brain images and are used to detect any abnormalities within it.
  • when patients need frequent imaging for diagnosis or continuous monitoring during treatment.

Risk and Disdvantages of CT Scan and MRI Scan

Despite the advantages of imaging tests in diagnosing issues, they can be harmful when not safely used. Possible risks of CT scans are:
  • Like X-rays, CT scans use radiation, which can cause cancer. That's why doctors don't usually recommend getting too many of them.
  • Use of dye as a contrast agent may cause allergies to your body, though in rare cases.
  • If you are pregnant, your unborn baby is at risk when you’re exposed to radiation. But a CT scan poses no known risks to your baby if the area of the body being imaged isn't the abdomen or pelvis.
Doctor examining imaging tests on computer The disadvantages of an MRI are:
  • An MRI is more expensive than a CT scan due to the expensive equipment used.
  • The presence of metal in your body, such as IUD and cochlear implants, can be a safety hazard or distort the MRI images. Other metals are artificial heart valves, joints, pacemakers, and implanted nerve stimulators. Some darker tattoo inks contain metal and may also interfere with the test.
  • MRIs may also use dyes, which may cause irritation or allergies.
  • MRI machines can be loud, but wearing earplugs or headphones to listen to music will help during the procedure.
  • Movement during the MRI procedure will blur the images, so you must lay very still while the scan is on.
  • MRI scans can be lengthy, which can cause anxiety, particularly if you’re claustrophobic. Open MRI machines are less confining and can remove some of these concerns, although they typically don’t produce images as detailed as those from regular MRI machines.

Visit Lancaster Orthopedic Group for an Accurate Diagnosis

Knowing the difference between CT scans and MRIs is a great first step. But if you want a clear diagnosis and a treatment plan that's right for you, you need to see an orthopedic specialist. At Lancaster Orthopedic Group, our team of experienced physicians will guide you in taking the appropriate imaging tests.  We prioritize recommending the option with the lowest risk and highest benefit for you. We’ll interpret your scans, figure out what's causing your pain, figure out what's causing your pain, and give you options for treatment that will actually work. Contact Lancaster Orthopedic Group today to schedule a consultation. We have the latest imaging technology and a team of experienced doctors who are ready to help. Don't let pain hold you back – take control of your health and get back to living your life to the fullest.

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