All You Need To Know About MRI Of The Body
A magnetic resonance imaging of the body is a test that utilizes a powerful magnetic field with radio waves and a computer to produce detailed images of the inside of an individual’s body. The test is also known as an MRI and can be used to assist with the diagnosis or monitoring of treat for a plethora of conditions within the abdomen, chest and pelvis. If you are pregnant, an MRI of the body can be used to safely monitor the state of the baby.
It is essential that you inform the doctor of any health conditions, recent surgeries, allergies or possibility of pregnancy before undergoing an MRI. While the magnetic field is not a harmful area, it may result in medical devices malfunctioning. The majority of orthopedic implants do not pose a risk, but it is always more beneficial to inform the technologist if you have any metal devices or implants in your body. It is recommended that you leave jewelry at home and wear comfortable, loose clothing. Some facilities require the individual to change into a gown.
Guidelines regarding eating and drinking between the MRI examinations will vary between facilities and, unless you are told otherwise, it is recommended that you continue taking medication as per usual if necessary. If you suffer from anxiety or claustrophobia, it may be worthwhile speaking with your doctor about using a mild sedative before the examination. This could help make the experience less stressful.
What Is The MRI Of The Body?
The magnetic resonance imaging test, also known as MRI, is a non-invasive procedure used by physicians to diagnose certain medical conditions. The procedure utilizes a powerful magnetic field with radio frequency pulses and a computer producing detailed images of soft tissues, organs, bones and all other internal bodily structures or systems. It must be noted that the magnetic resonance imaging test does not use any ionizing radiation.
A detailed MRI image is beneficial for patients because it allows doctors to evaluate the different parts of a body and identify the presence of any medical conditions. The images can be examined on a computer screen, transmitted electronically and printed or copied to a disc or uploaded to a digital server.
What Are The Typical Uses Of The MRI?
An MRI of the body is typically used to evaluate the organs of the abdomen and chest including the liver, the heart, the kidneys, the biliary tract, the spleen, the pancreas, the bowels and the adrenal glands. It also examines organs of the pelvis including the reproductive organs – uterus and ovaries in females and prostate in males – and the bladder. Further uses include evaluation of the blood vessels and the lymph nodes.
Medical professionals will also utilize magnetic resonance imaging to assist with the diagnosis or monitoring treatment of specific medical conditions. The most common conditions examined include tumors in the chest, pelvis and abdomen, heart problems, diseases of the liver, inflammatory bowel disease, malformations of the blood vessels or inflammation of the blood vessels, and a fetus in the womb of a pregnant female.
How Can I Prepare For The MRI Procedure?
It is typical that you will be asked to wear a hospital gown during the MRI procedure; however, you may be allowed to wear your own clothing if it is suitable – does not have any metal fasteners or clips and is loose.
As is mentioned above, the guidelines regarding drinking and eating before an MRI examination will vary according to the facility and the date of the procedure. Unless you are informed otherwise, it is recommended that you continue with your daily consumption routine eating food and taking medication as usual.
While some MRI procedures will require you to receive an injection of contrast material into the bloodstream, it is important that the radiologist, technologist or nurse administrating the injection ask about allergies of any kind. It is important that you make the team aware of allergies to iodine or x-ray contrast material, different foods, pharmaceuticals, environmental substances and if you have asthma.
The contrast material typically used in magnetic resonance imaging procedures contains a metal known as gadolinium. This metal can be used in most patients regardless of allergies, for example patients with an iodine contrast allergy. Furthermore, it is less likely for a patient to present with an allergy to gadolinium-based contrast materials than an iodine-based contrast material often used for CT scans. However, it is still important that allergies are checked and identify whether or not the patient has an allergy to gadolinium contrast. Patient consent will be requested in this situation. For more information regarding adverse reactions to different gadolinium-based contrast materials, check the ACR Manual on Contrast Media.
It is also highly recommended that the radiographer is informed of any serious health conditions or if you have experienced any recent surgeries. Certain medical conditions, such as severe kidney disease, can prevent you from receiving a gadolinium-based contrast material injection for the MRI procedure. If you present with a history of kidney disease or have been the recipient of a liver transplant, it is necessary to performance a blood test first to identify whether or not your kidneys are functioning at an adequate level to undergo an MRI for the body.
Women should always inform the medical staff (physicians and technologists) of a possibility that they are pregnant. The magnetic resonance imaging test has been utilized since the 1980s to scan patients with no reports of damage caused to pregnant women and their unborn children; however, this does not mean there is no risk of adverse effects to the unborn baby. Due to the fact that the unborn child will be placed in a strong magnetic field, it is recommended that the pregnant female does not undergo an MRI in the first trimester of her pregnancy unless the benefits of the examination outweigh the risks. A pregnant female should not receive any injections of gadolinium-based contrast material except if absolutely necessary for medical procedures. For more information on pregnancy and MRI, see the MRI safety page.
If you suffer from a fear of small and enclosed areas, also known as claustrophobia, or anxiety, it may be beneficial to speak with your doctor about a prescription for a sedative before the MRI procedure. This will help make the scheduled examination less stressful and more manageable.
It is essential that jewelry and all other accessories are left at home, if possible, and removed before attending the MRI examination. This is necessary because jewelry and other metal accessories can influence the magnetic field of the MRI unit interfering with the examination. In addition to adversely affecting the magnetic field and MRI images, the metal objects can become dangerous items within the MRI scanning room and can act as projectiles placing you and others at risk of harm. The items that should be removed and left at home include jewelry, watches, credit cards, hearing aids, hair pins, pins, metal zippers and other metallic items. It is also recommended that you remove all dental work, eyeglasses, pens, pocket knives and body piercings.
In the majority of cases, a magnetic resonance imaging procedure is safe for patients with metal implants; however, there are certain types of implants that cannot be scanned and these people should not consider entering the MRI scanning area. Individuals with cochlear or ear implants, implant clips for brain aneurysms, metal coil implants in blood vessels, pacemakers and all other types of cardiac defibrillator implants should avoid MRI procedures.
It is essential that you inform the radiographer or technologist of any electronic or medical devices implanted in your body. The object may interfere with the procedure and can, in some cases, pose a risk of harm to you and others in the room. This is dependent on the nature of the implant and the strength of the MRI scanning magnet.
The majority of devices will have pamphlets explaining MRI risks for that particular implant and if you have this type of pamphlet; it may be beneficial to inform the scheduler when making an appointment for an MRI. It is also recommended you bring the pamphlet to the MRI scan in case the technologist or radiographer has any concerns or queries. Certain implanted devices will require a period of time after placement before any other procedures can be conducted, particularly the MRI examination. The typical time is six weeks and some examples of these devices include, but are not limited to, implanted drug infusion ports, artificial heart valves, artificial limbs or joint prostheses, and implanted nerve stimulators.
If there are any concerns regarding the presence of a metal implant, it is possible to perform an x-ray to detect and identify the object. Typically, a metal object used in orthopedic surgery will pose no risk for magnetic resonance imaging; however, recently placed artificial joints could be problematic and may require a different types of imaging procedure.
A patient who may have metal objects in certain parts of his or her body may require an x-ray before undergoing an MRI examination. It is recommended that you notify the medical staff of any bullets, shrapnel or other metal debris or items that may be lodged in your body due to accidents. Any foreign objects near or in the eyes are of particular significant because they can move during the MRI scan, potentially resulting in blindness. Contrary to belief, tooth fillings and braces are not influenced by the magnetic field but they may distort the images of the facial area, so it is worthwhile informing your radiographer of these. Furthermore, dyes in tattoos can contain iron which may heat up during an MRI procedure, although this is rare.
Young children and infants will often require some form of sedation when undergoing a magnetic resonance imaging scan. To determine if the child requires anesthesia will depend on the age of the child, the child’s intellectual development and the type of examination. A moderate and conscious sedation is available at the majority of facilities and physicians specializing in sedation of children should be available to monitor the patient during the procedure. Special instructions for adequate preparation of the child can be received from the facility.
Alternatively, specific pediatric medical facilities have child life personnel who work with young children helping them avoid the need for sedation during an MRI scan. The personnel will prepare the children for the scan by demonstrating the procedure using a dummy scanner and playing noises the child may hear during the examination. The professionals will also answer any questions the child has and can explain the scan thoroughly relieving anxiety before the procedure takes place. Certain pediatric facilities also offer headsets or goggles for the children allowing them to watch a film while the scan is being conducted.
What Does The MRI Equipment Look Like?
The traditional MRI equipment involves a large cylindrical tube surrounded by circular magnets. The patient lies on the moveable examination table which slides into the center of the cylindrical tube.
Some MRI units have been designed so that the circular magnet does not surround the tube entirely. This type of unit is known as a short-bore system and presents with a larger diameter making it comfortable for larger patients or patients with claustrophobia. The machines are open on the sides and can provide very high quality of MRI scans.
The computer workstation processing the imaging information is located outside of this magnetic range within a separate room from the scanning equipment.
How Is An MRI Of The Body Performed?
MRI scans could be performed on inpatients as well as outpatients. The patient is positioned on a moveable examination table for this purpose. Straps are used to maintain the correct position and keep the patient still during the procedure. Devices that are capable of sending and receiving radio waves are placed adjacent to the study area of the patient’s body to perform the scan. Sometimes, a contrast material is used during the scan. Under such circumstances, a doctor or a technician would insert an intravenous catheter (IV) or IV line into a vein in the patient’s hand or arm. In fact, a saline solution is used to inject the contrast material. This solution will drip through the IV until the contrast material is injected.
The patient is then placed on the magnet of the MRI scanner. The technician will perform the scan – he or she would be working at a computer outside the room. If there is a necessity of injecting a contrast material, it would be injected into the IV line after the initial scans. Another series of images will be taken after the injection.
Once the initial scans are completed, the technician will request the patient to wait a while until he or she checks the scans. If additional images are not required, the IV line would be removed. Most of the time, MRI scans are conducted in multiple runs or sequences. The process may last for several minutes at times. The entire process may take between 30-50 minutes depending on the equipment used and the type of scan.
What Will The Patient Experience During And After The Procedure?
Although some patients may find it uncomfortable to be still during the procedure, most MRI scans are painless. There are some patients who have complained of having a feeling of being closed-in (claustrophobia) during the scan. If the patient feels anxious, the doctor may recommend appropriate sedation. But only fewer than one in 20 patients require such arrangements.
The area of the body that is being imaged can feel a bit warm during the scan. It rarely bothers the patient. If it bothers you, you should bring it to the notice of the technician. The patient needs to remain perfectly still during the process. The process is only a few seconds or a few minutes at a time. You may hear and feel loud thumping or tapping sounds when the coils of the unit are activated. That way you know the scanning process has begun. The patient may be given earplugs or headphones to reduce the intensity of the sounds made by the scanner. You can relax while the process goes on. But you should not move about when the process is being conducted. Movements can interfere with the accuracy of the scan.
Although you would be alone in the exam room during the MRI procedure, the technician can see, hear or speak with you using a two-way intercom. Most MRI centers allow a relative or friend to stay with the patient. But they should be screened for safety in the magnetic environment before getting the green light to stay.
Children are given earplugs and headphones during a scan procedure. The exam room is well-lit and air conditioned. Most of the time, music is played through the headphones to allow the patient to relax and pass the time. When IV lines are used during the scanning process, the needle may cause some bruising and discomfort. Some patients have complained of a slight irritation at the site of the IV tube insertion. But this is very rare. Most patients tend to feel a metallic taste in their mouths once the contrast injection is inserted.
Patients who don’t need any sedation can resume their normal diets and activities soon after the scanning procedure. There is no recovery period for such patients. There were very few instances where patients have complained of side effects such as nausea, pain at the site of the injection, and headaches from the contrast material. A small percentage of patients have complained of allergies to the contrast material such as itchy eyes, hives, and other reactions. If you experience such symptoms, you should notify the technician immediately. A physician will be available for immediate assistance under such circumstances.
How Will I Get To Know The Results? Who Interprets Them?
A physician, radiologist, or a trained technician can interpret the results of a radiology examination. They will send a sized report to your primary care physician who will share the results with you. If a follow-up examination is required, your family doctor will tell you why you need such a scan. Most of the time, a follow-up MRI scan is performed due to a potential abnormality requiring further evaluation with additional views. A follow-up image may also be required to see if there are any changes in the know abnormality over time. That is the best way to see how effective the treatments are and if the condition becomes stable over time.
The Benefits And Risks Of An MRI
Benefits –
. An MRI scan is a non-invasive imaging technique that doesn’t involve any exposure to ionizing radiation.
. MRI scans help get a better understanding of the soft tissue structures of the body such as the liver, heart, and other important organs. These images are important to identify certain diseases more accurately compared to other imaging methods. That is why an MRI is an invaluable tool in the early diagnosis of numerous tumors and focal lesions.
. MRI scans help diagnose a broad range of conditions such as cancer, bone diseases, muscular diseases, and heart diseases. These scans can easily identify most of the abnormalities in the important organs of the body that might have been obscured by the bone structure with other imaging techniques.
. MRI scans help the physician assess the biliary system without any contrast injections and surgery. On the other hand, the contrast used in the process is less likely to produce any allergic reaction compared to iodine based materials used for traditional x-rays and CT scanning.
. MRI is a non-invasive alternative to angiography, x-ray, and CT scanning for diagnosing issues in the heart and blood vessels.
Risks –
. The process doesn’t have any risk to the average patient when safety guidelines are properly followed. There is a risk of excessive sedation when sedation is used for the procedure. But the technologist or nurse will monitor the vital signs of the patient to minimize any risk.
. Even though the strong magnetic field in the MRI scanner is not harmful by itself, the implanted medical devices that contain metal can malfunction and cause issues during the procedure.
. Nephrogenic systemic fibrosis is a rare side effect that is caused by the injection of high doses of gadolinium-based contrast material in patients who are suffering from kidney failure. Careful assessment of the kidney functions of the patient before injecting the contrast material will minimize such a risk.
. Allergic reactions to the contrast materials were noted in some patients. These reactions and mild and could be controlled with a mild medication. The physician or technician should be available for immediate assistance if you experience such reactions.
. Manufacturers of IV lines have indicated that mothers should not breastfeed their babies for 48 hours after the contrast material is given. But the European Society of Urogenital Radiology and the ACR – American College of Radiology – says that it is safe to continue to breastfeed the baby after receiving the contrast.
Limitations Of MRI Of The Body
The quality of the image may depend on the stillness of the patient. He or she should follow the breath-holding instructions provided by the technician for high-quality images from the process. If the patient is anxious or in severe pain, the quality of the image can suffer. On the other hand, a very large person may not fit into the opening of certain types of MRI scanners.
Patients with implants and other metallic objects may not give a quality image. An irregular heartbeat may affect the quality of the scan when electrocardiography (EKG) are taken.
Breathing can cause image distortions during an MRI of the chest, pelvis or abdomen. But these issues could be minimized with the latest state-of-the-art scanners.
Pregnant women are advised to stay away from MRI scans during the first trimester unless it is mandatory. But there is no evidence to prove that magnetic resonance imaging harms the fetus. MRI scans will always not distinguish between cancer tissues and edema. The process may cost more and take more time to complete than other imaging techniques.