Magnetic resonance imaging (MRI) is an imaging test that uses a magnetic field and computerized radio waves to detailed images of the organs and tissues inside your body.
Most magnetic resonance imaging (MRI) machines are large, tube-shaped magnets. When you lie inside a magnetic resonance imaging (MRI) machine, the magnetic field temporarily affects the water molecules in your body and rearranges them. Radio waves cause these regular atoms to emit weak signals, which are used to cross-sectional magnetic resonance (MRI) images - like slices of bread.
The MRI machine can also 3D images that you can view from different angles.
Why is this being done
Magnetic resonance imaging (MRI) is a non-invasive method used by a doctor to examine the organs, tissues, and the skeleton. It produces high-resolution images of the inside of the body that help diagnose a wide variety of problems.
Magnetic resonance imaging (MRI) of the brain and spinal cord
Magnetic resonance imaging (MRI) is the most commonly used imaging test of the brain and spinal cord. It''s often done to help diagnose:
Cerebral aneurysms
Disorders of the eye and inner ear
Multiple Sclerosis
Spinal cord disorders
brain attack
Tumors
Traumatic brain injury
A special type of MRI is functional magnetic resonance imaging (fMRI) of the brain. It produces images of blood flow to specific areas of the brain. It can be used to examine the anatomy of the brain and to identify the parts of the brain that deal with vital functions.
This helps identify areas important for language control and movement in the brains of people who undergo brain surgery. Functional magnetic resonance imaging may also be used to evaluate damage from a head injury or from disorders such as Alzheimer''s disease.
Magnetic resonance imaging (MRI) of the heart and blood vessels
MRI scans that focus on the heart or blood vessels evaluate
The size and function of the cardiac chambers
Thickening and movement of the walls of the heart
The extent of damage caused by a heart attack or heart disease
Structural problems in the aorta, such as aneurysms or dissections
Inflammation or blockage of blood vessels
Magnetic resonance imaging (MRI) of other internal organs
An MRI can check for tumors or other abnormalities in many parts of the body, including the following:
Liver and bile ducts
The kidneys
Spleen
Pancreas
uterus
Bleachers
Prostate
Magnetic resonance imaging of bones and joints
An MRI will help detect any
Joint deformities caused by traumatic or repeated injury, such as torn cartilage and ligaments
Abnormalities in the vertebrae of the spine
Bone infection
Bone and soft tissue tumors
Breast magnetic resonance imaging
Magnetic resonance imaging may be used with a mammogram (mammogram) to monitor breast cancer, especially in women whose breast tissue has a high density or increased risk of cancer.
To risk
Because an MRI uses a strong magnet, the presence of metal in your body can pose a safety hazard to you when it is attracted to the magnet. Even if metals are not attracted to the magnet, metallic objects can distort the MRI images. Before an MRI scan, you''ll likely complete a questionnaire that includes indicating whether you have metal or electronic devices in your body.
You might not be able to have an MRI scan unless your available device is certified as safe for an MRI scan. Devices include:
Joint prostheses
An artificial heart valve
Implantable defibrillator
Implanted medication infusion pump
Implanted neurostimulants
Pacemaker.
Metal clamps
Metal staples, screws, slides, stents or surgical staples
Cochlear implantation
Bullet, shrapnel, or other kind of metal splinters
IUD
If you have had permanent tattoos or makeup, talk to your doctor about how it affects an MRI. Some dark pigments contain minerals
Before scheduling an MRI, tell the doctor if you think you might be pregnant. The effect of magnetic fields on fetuses is still not fully understood. Your doctor may recommend an native screening or postponing the MRI scan. Also tell your doctor if you are breastfeeding, and especially if you will receive a contrast medium during the exam.
It is also important to discuss any impaired kidney or liver function with your doctor and a radiologist, as impaired function of these organs can limit the possibility of using contrast agent injections during the scan.
How to prepare
Before an MRI scan, eat your meals normally, and continue to take your medications unless your doctor gives you other directions. Usually, you will be asked to change your clothes, wear a medical gown, and dispose of your belongings that may affect the magnetic imaging, such as:
Jewelry
Hairpins
Eye glasses
hours
fake hair
Industrial dentures
Hearing aids
Metal bras
Any cosmetics that contain mineral parts
What you can expect
While taking the test
The MRI machine looks like a long, narrow tube with two open ends. You will lie on your stomach on a movable table that slides into a tube opening. A technician is watching you from another room. You can talk to the person via the microphone.
If you have a fear of closed spaces (claustrophobia), you may receive medication to help you feel sleepy and reduce your stress and anxiety. Most people take the test without much difficulty.
The MRI machine s a strong magnetic field around you, and through it, radio waves are directed at your body. This process is painless. You will not feel the magnetic field, nor the radio waves, and there will be no moving objects around you.
During a CT scan, the inside of the magnet produces repetitive clicks, knocks, and other sounds. You may be given earplugs or playing music to help block out the noise.
In some cases, a contrast material, usually gadolinium, is injected through an intravenous (IV) line into a vein in your hand or arm. The contrast material enhances some detail. Gadolinium rarely causes allergic reactions.
An MRI can take anywhere from 15 minutes to over an hour. You should stay still because movement can make the resulting images blurry.
During a functional MRI, you may be asked to do a number of small tasks - such as tapping your thumb over your fingers, rubbing a bunch of sandpaper, or answering simple questions. This helps identify the parts of your brain that control these actions.
After taking the test
If you do not take any drugs, you can go about your usual activities once the scan is finished.
Results
A doctor specially trained in interpreting MRI images (radiologist) analyzes the images of your scans and reports the results to your doctor. Your doctor will discuss the important results and next steps with you.
