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In our previous blog, we have discussed about MRI scan. Please check out for the link given below.

MRI scan

In today's blog we are going to discuss about MRI with contrast.

MRI scan is usually done in two methods, with contrast and without contrast. One main difference between both methods is that a special type of dye is injected in MRI with contrast which yields better results in terms of image quality and image interpretation. Therefore it is important for every healthcare professionals to know about MRI with contrast.

Let's get into the topic.

WHAT IS AN MRI WITH CONTRAST?

The first MRI scan on humans was done on 1977. Later in 1988, Gadolinium based contrast agents are used to enhance MRI images. In MRI with contrast, a gadolinium based contrast agents, a paramagnetic metal ion which is used because of its property to travel with magnetic fields. It is a MRI dye used to enhance the image quality during MRI scan.

Generally bones and air spaces in human body appears as black colour in MRI scan. Soft tissues based on the amount of fat and water present, will appear from gray to black in MRI scan. When MRI contrast is injected into the bloodstream, the tissues targeted will appear brighter.

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HOW CONTRAST IS INJECTED?

In MRI with contrast, the contrast agents are admitted intravenously in the arm or administered orally. The contrast agents are injected with a use of IV or butterfly needle. Injection process will take 10 to 30 seconds. Approximately around 10 to 20 millilitres of gadolinium based contrast agents are injected into the veins.

WHO NEEDS MRI WITH CONTRAST?

Generally MRI with contrast is preferred for patient’s based on doctor’s prescription. When a doctor feels that his patient requires a contrast agent to increase the image quality, he prescribes it. And also doctor considers the patient’s past medical history to prescribe the use of contrast agents. Contrast agents do not change the colour of the organs, instead it changes the way in which imaging modalities views your organs. Later these contrast agents are excreted via urine.

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WHAT ARE THE ADVANTAGES OF

MRI WITH CONTRAST?

1. The MRI with contrast is mostly preferred for tumor patient’s. Because the doctors can identify even a smallest tumors with the help of contrast agents. Generally tumors are more vascularized. They have lot of blood vessels feeding into them. If a contrast agent is injected, a lot of it will flow through the blood vessels and reach the tumors. So in MRI with contrast, tumors appears more brighter than surrounding tissues. Useful in determining the growth stage of tumors.

2. MRI with contrast can visualize moving blood in arteries whereas normal MRI without contrast can produce the images of arteries as a void space.

3. The MRI with contrast is said to be most useful in imaging of multiple sclerosis.

4. No other additional scans required because MRI with contrast provides an enhanced image quality. With that doctors can easily interpret all the details in a single scan.

5. Interpretation time and difficulty also decreases.

WHAT ARE THE SAFETY CONCERNS OF MRI WITH CONTRAST?

1. In MRI with contrast, the injected contrast agents are excreted via urine, patient’s with poor kidney functions may have problem in excreting the contrast agents. As a result the Gadolinium based contrast agents may remain in the body and cause a condition called Nephrogenic systemic failure. It causes thickening of skin and tissues.

2. MRI with contrast in some cases may cause allergic reactions, skin irritations and pain in the injection site.

3. In MRI with contrast, the use of gadolinium based contrast agents are considered to be harmful for pregnant women’s and fetus. However MRI without contrast agents is proved to be safe for pregnant women’s and fetus.