Magnetic resonance imaging (MRI) is a medical imaging technique that uses a magnetic field and computer-generated radio waves to create detailed images of your body's organs and tissues.
Large, tube-shaped magnets are used in the majority of MRI machines. For a brief period of time, the magnetic field in an MRI machine realigns water molecules in your body. These aligned atoms emit faint signals, which are used to create cross-sectional MRI images, similar to slices in a loaf of bread.
The MRI machine can also create three-dimensional images that can be viewed from various perspectives.
Why is it done this way?
Your doctor can use an MRI to examine your organs, tissues, and skeletal system in a non-invasive way. It generates high-resolution images of the inside of the body to assist in the diagnosis of a variety of illnesses.
Magnetic resonance imaging (MRI) is the most common imaging test for the brain and spinal cord (MRI). It's commonly used to diagnose:
- Cerebral aneurysms
- Eye and inner ear disorders
- Multiple sclerosis
- Spinal cord disorders
- Stroke
- Tumors
- Traumatic brain injury
The functional MRI of the brain is a unique type of MRI (fMRI). It generates images of blood flow to specific brain areas. It can be used to look at the anatomy of the brain and figure out which parts of the brain are in charge of critical functions.
Damage from a head injury or disorders like Alzheimer's disease can also be assessed using functional MRI.
The heart and blood vessels are imaged using magnetic resonance imaging (MRI).
- The size and function of the heart's chambers can be assessed using an MRI that focuses on the heart or blood vessels.
- Heart wall thickness and movement
- Amount of damage caused by heart attacks or heart disease
- Aorta structural issues, such as aneurysms or dissections
- Inflammation and blockages in the blood vessels
Other internal organs MRI
Many organs in the body can be checked for tumors or other abnormalities using MRI, including the following:
- Kidneys
- Spleen
- Pancreas
- Uterus
- Ovaries
- Prostate
- Liver and Bile Ducts
- MRI scans of the bones and joints
- Joint abnormalities caused by traumatic injuries
- Spine abnormalities
- Bone infections
- Bone and soft tissue tumors
MRI can help evaluate:
A breast MRI is a type of MRI that looks at the inside of the breast
Breast cancer can be detected using MRI in conjunction with mammography, especially in women who have dense breast tissue or are at high risk.
Risks
Because MRI uses strong magnets, any metal in your body that is attracted to the magnet can pose a safety risk. Metal objects can distort an MRI image even if they are not attracted to the magnet. Before getting an MRI, you'll probably have to fill out a questionnaire that asks if you have any metal or electronic devices in your body.
You may not be able to have an MRI unless your device is certified as MRI safe. The following are examples of devices:
- Joint prostheses made of metal
- Prosthetic heart valves
- A defibrillator that can be implanted in the heart
- Drug infusion pumps that have been implanted
- Nerve stimulators implanted
- The use of a pacemaker
- Clips made of metal
- Surgical staples, pins, screws, plates, stents, or metal pins
- Cochlear implants are a type of cochlear implant that is used
- Any type of metal fragments, such as a bullet, shrapnel, or shrapnel.
- intrauterine device
If you have tattoos or permanent makeup, check with your doctor to see if they could interfere with your MRI. Metal is present in some of the darker inks. If you think you're pregnant, tell your doctor before scheduling an MRI.
Magnetic fields' effects on fetuses aren't well understood. Your doctor may suggest a different exam or a postponement of the MRI. Tell your doctor if you're breastfeeding, especially if you'll be receiving contrast material during the procedure.
It's also crucial to discuss any kidney or liver issues with your doctor and the technologist, as these organs may limit the amount of injected contrast agents that can be used during your scan.
How do you get ready?
Before an MRI exam, eat normally and take your regular medications unless otherwise directed. You'll almost certainly be asked to put on a gown and remove anything that could interfere with the magnetic imaging, such as jewelry.
- Jewelry
- Hairpins
- Eyeglasses
- Watches
- Wigs
- Dentures
- Hearing aids
- Underwire bras
During the examination
The MRI machine resembles a long, narrow tube with two open ends. You sit on a movable table that slides into the tube's opening. From another room, a technologist keeps an eye on you. You can use the microphone to communicate with the person.
If you have claustrophobia (a fear of enclosed spaces), you may be prescribed a drug to help you sleep and feel less anxious. The majority of people breeze through the exam.
The MRI machine surrounds you with a strong magnetic field and directs radio waves at your body. It is a painless procedure. There are no moving parts around you, and you don't feel the magnetic field or radio waves.
During an MRI scan, the internal part of the magnet makes repetitive tapping, thumping, and other noises. To help block out the noise, you may be given earplugs or music may be played.
In some cases, a contrast material, usually gadolinium, will be injected into a vein in your hand or arm via an intravenous (IV) line. Certain details are enhanced by the contrast material. Gadolinium causes allergic reactions in a small percentage of people.
An MRI can take anywhere from 15 minutes to over an hour to complete. You must remain motionless because movement will cause the images to blur.
You may be asked to do a variety of small tasks during a functional MRI, such as tapping your thumb against your fingers, rubbing a block of sandpaper, or answering simple questions. This allows you to pinpoint which parts of your brain are in charge of these actions.
Following the examination
You can resume your normal activities right after the scan if you weren't sedated.
Results
The images from your scan will be examined by a radiologist (a doctor who is specially trained to interpret MRIs) and the results will be reported to your doctor. Your doctor will discuss the most important findings and next steps with you.