If you are allergic to contrast dye, your doctor may opt for a non-contrast scan. If you absolutely must use contrast, your doctor may prescribe steroids or other drugs to help you avoid an allergic reaction.
The contrast dye you were given will be naturally removed from your body through your urine and faeces after the scan. Because contrast dye can put a strain on the kidneys, you may be advised to drink plenty of water after your procedure.
Magnetic resonance imaging (MRI) of the body creates comprehensive images of the inside of the body using a powerful magnetic field, radio waves, and a computer. It can be used to diagnose or track the progress of treatment for a number of chest, abdominal, and pelvic diseases. The doctor may utilise body MRI to carefully monitor your baby if you are pregnant.
Tell your doctor if you have any health concerns, recent surgeries, or allergies, as well as if you think you could be pregnant. Although the magnetic field is not dangerous, it has been known to cause medical devices to malfunction. Although most orthopaedic implants are safe, you should always inform the technician if you have any gadgets or metal in your body. The rules for eating and drinking before your exam differ depending on the facility. Unless otherwise directed, continue to take your regular medications. Wear loose, comfy clothing and leave your jewels at home. It’s possible that you’ll be requested to put on a robe. If you experience claustrophobia or anxiety, you may wish to get a little sedative from your doctor before the exam.
Your doctor can use an MRI to check your organs, tissues, and skeletal system in a noninvasive approach. It creates high-resolution images of the inside of the body to aid in the diagnosis of a wide range of ailments.
MRI is the most frequently used imaging test of the brain and spinal cord. It’s often performed to help diagnose:
The functional MRI of the brain is a unique sort of MRI (fMRI). It generates images of blood flow to specific brain locations. It may be used to look at the structure of the brain and figure out which areas of the brain are in charge of essential functions.
This aids in the identification of critical language and movement control areas in the brains of persons undergoing brain surgery. Damage from a head injury or illnesses like Alzheimer’s disease can also be assessed using functional MRI.
MRI that focuses on the heart or blood vessels can assess:
MRI can check for tumors or other abnormalities of many organs in the body, including the following:
MRI can help evaluate:
MRI can be used with mammography to detect breast cancer, particularly in women who have dense breast tissue or who might be at high risk of the disease.
You’ll need to change into a hospital gown before proceeding. This is done to avoid artefacts in the final photos and to adhere to safety rules regarding the strong magnetic field.
The rules for eating and drinking before an MRI differ depending on the procedure and the facility. Unless your doctor advises you otherwise, eat and take your meds as usual.
An injection of contrast material is used in some MRI scans. To contrast material, drugs, food, or the environment, the doctor may inquire if you have asthma or allergies. Gadolinium is a typical contrast substance used in MRI scans. In patients who are allergic to iodine contrast, doctors can utilise gadolinium. Gadolinium contrast is far less likely to cause an allergic reaction than iodine contrast. Even if the patient has a known gadolinium allergy, it may be possible to utilise it with proper pre-medication. Please see the ACR Manual on Contrast Media for more information on allergic responses to gadolinium contrast.
If you have any major health conditions or recent surgeries, tell the technologist or radiologist. You may not be able to get gadolinium if you have certain medical issues, such as severe kidney illness. A blood test may be required to ensure that your kidneys are functioning appropriately.
If a woman is pregnant, she should always tell her doctor and technician. Since the 1980s, there have been no reports of MRI harming pregnant women or their unborn children. The newborn, on the other hand, will be exposed to a powerful magnetic field. As a result, pregnant women should avoid getting an MRI in the first trimester unless the benefits clearly outweigh the dangers. Gadolinium contrast should not be given to pregnant women unless it is absolutely required. More information on pregnancy and MRI can be found on the MRI Safety During Pregnancy page.
If you suffer from claustrophobia (the dread of being trapped in a small place) or anxiety, ask your doctor to prescribe a light sedative before your assessment.
You will typically be asked to change into a gown and to remove things that might affect the magnetic imaging, such as:
If you have any medical or electrical gadgets in your body, tell the technologist. These devices may obstruct the examination or constitute a risk. Many implanted devices come with a leaflet that explains the device’s MRI hazards. Bring the booklet to the scheduler’s attention before the exam if you have it. Without confirmation and documentation of the type of implant and MRI compatibility, an MRI cannot be done. If the radiologist or technician has any questions, you should bring any pamphlets with you to your exam.
An x-ray can detect and identify any metal objects if there is any doubt. MRI does not pose a risk to metal devices utilised in orthopaedic surgery. A recently implanted artificial joint, on the other hand, may necessitate the use of a separate imaging exam.
Any shrapnel, bullets, or other metal in your body should be disclosed to the technologist or radiologist. Foreign bodies close or trapped in the eyes are particularly dangerous because they may move or heat up during the scan, resulting in blindness. Tattoo dyes may contain iron, which could cause an MRI scan to become too hot. This is unusual. Tooth fillings, braces, eyeshadows, and other cosmetics are normally unaffected by the magnetic field. These materials, however, may cause images of the face or brain to be distorted. Inform the radiologist of your findings.
To complete an MRI exam without moving, infants and young toddlers frequently require sedation or anaesthesia. The age of the child, his or her intellectual development, and the type of exam all play a role. Sedation is available in a variety of locations. For your child’s safety, a paediatric sedation or anaesthesia professional should be present during the examination. You will be given instructions on how to prepare your child.
Some clinics may employ staff who specialise in working with children in order to prevent the use of sedation or anaesthesia. They may show children a replica MRI scanner and recreate the sounds they might hear during the exam to help them prepare. They also answer any questions you might have and explain the procedure to help you relax. Some centres additionally supply goggles or headsets so that the youngster can view a movie while taking the test. This keeps the child still and enables for high-quality photographs.
The MRI machine resembles a long, narrow tube with two open ends. You sit on a movable table that slips into the tube’s aperture. From another room, a techie 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 medicine to help you sleep and feel less nervous. The majority of folks breeze through the exam.
The MRI equipment surrounds you with a powerful magnetic field and directs radio waves at your body. It is a painless operation. There are no moving things around you, and you don’t feel the magnetic field or radio waves.
The interior component of the magnet produces repetitive tapping, pounding, and other noises during the MRI scan. To assist block out the sounds, you may be given earplugs or music may be played.
In rare situations, a contrast substance, 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 produces allergic responses in a small percentage of people.
An MRI might take anywhere from 15 minutes to over an hour to complete. You must remain motionless because movement will cause the visuals to blur.
You may be asked to do a variety of modest tasks during a functional MRI, such as tapping your thumb on 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 movements.
You will be positioned on the mobile exam table by the technologist. To help you stay motionless and maintain your position, they may employ straps and bolsters.
Devices with coils capable of sending and receiving radio waves may be placed around or near to the part of the body being examined by the technologist.
Multiple runs (sequences) are usually included in MRI exams, some of which can span several minutes. Each run will provide a unique set of sounds.
A doctor, nurse, or technologist will place an intravenous catheter (IV line) into a vein in your hand or arm if your exam requires contrast material. The contrast substance will be injected through this IV.
You will be inserted into the MRI machine’s magnet. The exam will be performed by a technologist who will be working on a computer outside of the room. An intercom will allow you to communicate with the technologist.
After an initial set of images, the technologist will inject the contrast material into the intravenous line (IV). They’ll take more pictures before, during, and after the injection.
When the exam is finished, the technologist may ask you to wait while the radiologist reviews the images to see whether any more ones are needed.
After the exam, the technologist will remove your IV line and apply a tiny dressing to the insertion site.
The test is normally finished in 30 to 50 minutes, depending on the type of exam and the technology utilised.
The majority of MRI exams are painless. Some patients, on the other hand, find it difficult to remain still. Others may get claustrophobic feelings while in the MRI machine. The scanner can make a lot of noise.
It’s natural to feel a little warm in the part of your body that’s being photographed. Tell the radiologist or technologist if it disturbs you. It’s critical that you stay completely still while the photos are being shot. This usually lasts only a few seconds to a few minutes. You will hear and feel loud tapping or pounding sounds when photographs are being recorded. When the coils that generate the radio waves are energised, they make these sounds. To lessen the noise generated by the scanner, you will be given earplugs or headphones. It’s possible that you’ll be able to unwind in between imaging sequences. You must, however, maintain your stance as much as possible without moving.
In most cases, you will be alone in the exam room. Using a two-way intercom, the technician will be able to see, hear, and speak with you at all times. They will give you a “squeeze-ball” that will inform the technician that you require immediate assistance. If a friend or parent has been screened for safety, many facilities will allow them to stay in the room.
During the exam, children will be given earplugs or headphones that are the right size for them. To pass the time, music can be played over the headphones. The MRI scanners are well-lit and air-conditioned.
Before the images are taken, an IV injection of contrast material may be provided. You may have some discomfort and bruising as a result of the IV needle. There’s also a low danger of skin irritation at the IV tube’s insertion site. Following the contrast injection, some individuals may have a brief metallic taste in their mouth.
There is no need for a recovery period if you do not require sedation. After the exam, you can immediately resume your normal activities and diet. A few people may have negative effects from the contrast substance on very rare occasions. Nausea, headaches, and soreness at the injection site are all possible side effects. Patients with rashes, itchy eyes, or other adverse reactions to the contrast substance are quite rare. Tell the technician if you have any allergic reactions. A radiologist or other doctor will be available for immediate assistance.
The images will be analysed by a radiologist, a doctor who is trained to supervise and interpret radiology exams. Your primary care or referring physician will receive a signed report from the radiologist and will inform you of the results.
It’s possible that you’ll need a follow-up exam. If this is the case, your physician will explain why. A follow-up test may be necessary to further analyse a potential problem with more perspectives or a unique imaging technology. It may also check to determine if an issue has changed over time. Follow-up assessments are frequently the most effective approach to determine whether treatment is working or whether a problem requires addressing.