If your doctor has decided that you need to undergo a magnetic resonance imaging (MRI) exam with contrast, you may be wondering what purpose it serves. Not every MRI does, after all, require the injection of a contrast agent. But depending on your specific health and medical history as well your current condition, a contrast MRI may be just what your doctor needs to get the type of highly detailed images necessary to assess the area of interest.
So, what is it about the contrast that makes it appropriate for examining certain conditions and functions?
How it works
A contrast agent is a gadolinium-based dye that is injected into your arm intravenously. While MRI images produce cross-sectional views of your tissues, organs, bones, and joints in shades of gray — from white to black — the addition of the contrast acts like an illuminator. In other words, it helps the radiologist capture sharper and more detailed images of the areas that need to be examined.
To further explain: Without a contrast agent, hard bone, for example, appears black or very dark on the scan next to the grayish shades of bone marrow, spinal fluid, blood, and soft tissues. With contrast in the patient’s bloodstream, the targeted areas glow bright white, making them easier to detect and assess.
Quick and easy procedure
Just like a non-contrast MRI, the exam is painless and involves no radiation. It takes no more than half a minute or less to enter your blood vessels. Within one day, it leaves the body via your urine.
Keep in mind intravenous contrast exams are far from a necessity for all conditions. For orthopedic issues, non-contrast imaging is common. Also, for pregnant women and patients with compromised kidneys, MRIs without contrast is recommended.
When a contrast MRI may be needed
The addition of contrast tends to produce enhanced images of certain conditions and functions, such as:
- Inflammation
- Blood supply to certain organs
- Blood vessels
- Tumors
Let’s take a look at three conditions where the use of a contrast MRI can be helpful:
1. Multiple sclerosis
MRI scans are an important step in the diagnosis of multiple sclerosis (MS). While the initial detection does not require contrast, it can help the radiologist understand the progression of the disease by tracking the appearance of new lesions and the type of MS a patient has.
2. Cancer
The contrast enhances the appearance of tumors, making them easier to spot. It allows the radiologist to detect even the smallest tumor and its location. Around 30% to 50% of cancers are preventable, partly because of early detection.
So, to summarize: What’s the difference between a contrast and a non-contrast MRI?
- A contrast MRI helps produce sharper images, reducing the need for follow-up procedures.
- Due to the “illuminated” quality of the scans, contrast MRIs tend to be easier to interpret.
- An MRI with contrast can detect small tumors, and inform your doctor about their size, location, and surrounding tissues.
In the end, your unique situation determines which type of scan will yield the most optimal results.
Questions? Please reach out
The MRI images that your doctor ordered may be an important step toward your future health and well-being. If you have questions, please don’t hesitate to contact us. At University Medical Imaging, we are passionate about helping you feel comfortable and at ease.