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If you’re booked in for an MRI scan, it’s only natural to be nervous. But the best way of beating nerves? The more you know, the easier it’ll be.
Our guide to MRI scanning is just the ticket. Read on and you’ll find out everything you need to know about MRI scans, how they work, and their exceptional safety.
MRI Colorado: How does an MRI work?
MRI is short for magnetic resonance imaging. It is a technique which allows a technician- better known as a radiologist– to see high resolution images from within your body, without having to open you up. The idea is similar to that used in X-rays and CAT scans.
MRI, as per the name, uses magnetism to see within the body. MRI scanners create a strong magnetic field around you, and use radio signals to create the images. The scans that magnetic resonance imagery create allow radiologists to see even small changes in soft tissue, not just bone, like X-ray scans.
Magnetic resonance imagery can detect the smallest changes in muscle, tendon and other soft tissues. This helps radiologists to spot problems like tumors in fine detail, even when they are only just forming. It can form detailed images of the brain, and spot both brain tumors and the signs of strokes and plaques (which are present in conditions like Alzheimer’s).
MRI Colorado: How does magnetism help you look inside a body?
Now, this is where it gets a little complicated! In fact, most MRI technicians say that if you think you understand how MRI works, then… You don’t. So don’t worry if this all seems a little crazy.
Magnetic resonance imaging works because the human body is mostly made of water. Now, believe it or not, but when your body is placed within a strong magnetic field, the hydrogen nuclei within water become aligned with the field. Just like a piece of iron pointing towards a magnet, or a compass point pointing due north! As the MRI scanner sends radio signals through your body, the waves interact with the protons and push them back to their original positions. The small amount of energy that this creates is bounced back in the form of a radio signals. These are what the scanner picks up on, allowing it to make an image of your body.
Protons inside different kinds of tissue take more energy to push back into place means that an MRI can distinguish between different kinds of soft tissue. The strength of the magnetic field can be adjusted to better point out different kinds of tissue, as well. And if the radiologist needs to look at the movement of your blood, or soft tissue that needs blood to function (pretty much all of the stuff!), then they can inject you with a fluid that makes them stand out even more.
MRI Colorado: What does an MRI machine look like?
From the picture above, you can see what an MRI scanner looks like. It’s a large machine that you’ll be able to lie down in comfortably. You’ll spend most of your time during your visit inside it- and the inside normally doesn’t look too interesting. You should have enough room to move your head around without it banging into the side of the machine. But don’t worry- some clinics have a small mirror and TV set up so that you don’t get too bored!
MRI Colorado: Are there different kinds of MRI?
There are two main forms of MRI which are common in American clinics. The most common kind of MRI scan is the diffusion MRI, which measures the way that water moves inside biological tissue. This is what we were talking about earlier. Diffusion MRI allows the radiologist to identify tumors, which are of a different water content than the tissue around them, making them stand out.
The next is functional MRI, which is used to measure activity in the brain based on the flow of blood. This works because the flow of blood in the brain is connected to the way in which the brain works. So areas of the brain which are being used- let’s say for example Broca’s area, which is related to speech- require more blood than those that don’t. So when you speak, more blood flows to Broca’s area than did before. This fact allows the technician to examine the brain in action- which is amazing, when you think about it. There are other kinds of MRI like the phase contrast MRI and magnetic resonance spectroscopy, but these are less commonly used.
MRI Colorado: Last but not least, is an MRI safe?
MRI scanning is actually amazingly safe. This is because it doesn’t rely on radiation like other forms of scanning, such as X-rays. The only risk is if you happen to have some kind of metal in your body. So, for instance, screws left in your hip from an operation could pose a risk if you went for an MRI. This is why MRI scanning is almost never used as a first stage of diagnosis. And it’s never at all used without your medical records being thoroughly checked first.
The same goes for anybody wearing a pacemaker, although modern pacemakers are designed not to react to magnetic fields. Even so, your radiologist should be aware, or made aware, of anything along these lines before your scan. Even so, if you’re still unsure of how safe MRI scanning is, please feel free to contact us for more information– we’re always happy to help.