What are MRIs?
An MRI is a magnetic resonance imaging (MRI) machine. An MRI uses powerful magnets to create high-resolution images of your body’s internal organs and structures. These images are then compared with those taken from other types of X-rays or computed tomography (CT).
You may have heard the term “magnetic resonance” before, but what does it mean exactly?
The Magnetic Resonance Imaging (MRI) scanner measures the strength of the magnetic field produced by charged particles in the earth’s core. When these charged particles align themselves into a specific pattern, they produce an image of your body’s internal structure and tissues. MRI machines use different kinds of magnets to generate different strengths of fields, which allows them to produce very detailed images.
How do I get an MRI?
You can usually get an MRI without having to go through any sort of invasive procedure. Your doctor will probably ask if you want one done right away or wait until later in the day when you’re feeling better. If you choose to have an MRI, your doctor will perform a few tests first. They’ll check your vital signs, take some blood samples and maybe even give you a physical exam. You need to feel well for an MRI because they take a few minutes to set up and the process itself is fairly quick.
The technician or doctor will place you on the table when the testing begins. You’ll lie flat on your back with your head placed in a headrest. They’ll strap your body down to the table and cover your body with a blanket for warmth and comfort.
After they secure everything, they’ll move a device called a coil into the center of the chamber. The coil will be positioned right above your body and extended over your head. The technician or doctor will start the machine, take some safety precautions and then begin the scan.
How long does an MRI take?
The whole procedure takes about 20-30 minutes. You’ll have to hold still the entire time because even small movements can ruin the quality of the images. During the scan, it’s important to stay as still as possible. If you have to move at any point, let the staff know before you do. They’ll stop the scan and can restart it later.
How does an MRI work?
The entire machine is made up of a large donut-shaped magnet surrounded by a computer system. The computer controls the magnet’s strength and position, which in turn allows it to control the charged particles it emits. When you lie inside the machine, the charged particles in your body align with the magnetic field. This causes your body to absorb very small amounts of energy and as a result, they begin to move in different directions. It’s this movement that allows the computer to create detailed images based on where the particles move.
How is an MRI different from a CT or PET scan?
X-rays and CT scans work by exposing your body to a small amount of radiation in order to highlight specific aspects of internal organs and bones. The radiation is very small, but it’s best to limit exposure whenever possible. A PET scan uses a small amount of radioactive material that’s injected into your bloodstream. The material travels through your body and the scanner is able to highlight areas of high and low levels of activity.
How can I get an MRI?
You’ll need a doctor’s note in order to get an MRI. You can see a primary care physician, neurologist, or sleep specialist to get the referral. If you already know what’s wrong, get the referral from your primary doctor. If you need a specialist referral, go see a primary care physician first and explain your condition. He or she will determine the best course of action. Once you have the referral, you can schedule an appointment with any reputable medical imaging facility and they’ll give you the all clear to enter the scanner after a short physical to make sure you’re in good health.
How much does an MRI cost?
If you have medical insurance, they will probably cover the cost of the scan. Some plans require a referral from your primary care physician while others are more flexible and only require a referral from a specialist if the problem falls outside the scope of your primary physician’s training. Medicare and Medicaid will also cover the procedure, but you’ll have to meet certain income requirements in order to qualify.
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