An MRI of the brain usually takes minutes to perform. Your child will lie on the movable scanning table while the technologist places him or her into position. A special plastic device called a coil may be placed around your child's head. The table will slide into the tunnel and the technician will take images of the head. Each scan takes a few minutes. To detect specific problems, your child may be given a contrast solution through an IV.
The solution is painless as it goes into the vein. The contrast highlights certain areas of the brain, such as blood vessels, so doctors can see more detail in specific areas. The technician will ask if your child is allergic to any medications or food before the contrast solution is given. The contrast solution used in MRI tests is generally safe.
However, allergic reactions can occur. Talk to your doctor about the benefits and risks of receiving contrast solution in your child's case. As the exam proceeds, your child will hear repetitive sounds from the machine, which are normal. Your child may be given headphones to listen to music or earplugs to block the noise, and will have access to a call button in case he or she becomes uneasy during the test.
If sedated, your child will be monitored at all times and will be connected to a machine that checks the heartbeat, breathing, and oxygen level. Once the exam is over, the technician will help your child off the table; if sedation was used, your child may be moved to a recovery area. An MRI exam is painless. You may be told to drink lots of fluids to help your kidneys remove the contrast dye from your body. MRI is very safe. There are no known health risks associated with the magnetic field or the radio waves used by the machine.
Some people are sensitive to the contrast agent and may develop an allergic reaction. All contrast agents are FDA-approved and safe. Be sure to tell your doctor if you have diabetes or kidney problems.
In some cases a kidney function test may be needed prior to the MRI to make sure your kidneys are able to clear the contrast agent from your body. Any metallic substance on your body can affect the quality of the images. It can also cause discomfort or injury to you when placed in the magnetic field, and may exclude you from the exam. After the first trimester, there is no definitive research indicating that MRI is contraindicated in pregnancy.
However, you will need to obtain a written order from your gynecologist for the test to be performed. The radiologist will promptly review your images and communicate directly with your referring doctor, who in turn will discuss the results with you.
If you have further questions about this diagnostic test, contact the doctor that ordered the test or visit Radiologyinfo. X-ray: electromagnetic radiation used in diagnostic imaging to view shadows of tissue density in the body, also called roentgenogram.
We comply with the HONcode standard for trustworthy health information. This information is not intended to replace the medical advice of your health care provider. At Mayfield, we work with diagnostic imaging providers in the Greater Cincinnati-Northern Kentucky region to obtain images of the brain and spine and interpret them with expertise and care.
Patients and referring physicians can rest assured that we will lay the groundwork for a diagnosis of utmost accuracy. To make an appointment call Before you schedule your appointment for a brain MRI, make sure to inform the medical staff if you have any of the following conditions. Some items can pose a risk during an MRI. Make sure your doctor and medical staff know about any of the following items before you get your MRI:. Also, let your doctor know if you are unable to lie down for 30 to 60 minutes , or have had an allergic reaction to a contrast agent in the past that required medical treatment.
Lastly, know tattoos may cause discomfort during the test due to traces of metal in ink. Knowing what to expect can help calm any of your anxiety about your MRI. Here are typical steps involved with getting an MRI. First, medical technologists will instruct you to remove and store any metal materials in a lockable storage area. You may wear comfortable clothes that do not contain metal or change into medical scrubs top and pants or a hospital gown once you get to the MRI center.
Medical staff will guide you into a special room that holds the MRI scanner. An MRI machine looks like a giant tube with openings at both ends. Newer machines are bigger and provide more space, which may help ease claustrophobia. A short-bore system only scans the necessary part of the body, and allows the rest of the body to be outside of the magnet.
For this type of scanner, only the upper part of your body would be inside the tube for a brain MRI. With an open MRI, all sides of the machine are open. The technologist will give you a pillow or foam block to help keep your head in the right position. If you feel cold, a technologist can cover you with a sheet to make you more comfortable.
You might experience a flushing sensation or a metallic taste in your mouth for a few moments after the injection. Contrast agents rarely cause allergic reactions. Tell the technologist if you have medical or electronic devices in your body.
These devices may interfere with the exam or pose a risk. Many implanted devices will have a pamphlet explaining the MRI risks for that device. If you have the pamphlet, bring it to the attention of the scheduler before the exam.
MRI cannot be performed without confirmation and documentation of the type of implant and MRI compatibility. You should also bring any pamphlet to your exam in case the radiologist or technologist has any questions. If there is any question, an x-ray can detect and identify any metal objects.
Metal objects used in orthopedic surgery generally pose no risk during MRI. However, a recently placed artificial joint may require the use of a different imaging exam. Tell the technologist or radiologist about any shrapnel, bullets, or other metal that may be in your body. Foreign bodies near and especially lodged in the eyes are very important because they may move or heat up during the scan and cause blindness.
Dyes used in tattoos may contain iron and could heat up during an MRI scan. This is rare. The magnetic field will usually not affect tooth fillings, braces, eyeshadows, and other cosmetics. However, these items may distort images of the facial area or brain. Tell the radiologist about them.
Infants and young children often require sedation or anesthesia to complete an MRI exam without moving. This depends on the child's age, intellectual development, and the type of exam.
Sedation can be provided at many facilities. A specialist in pediatric sedation or anesthesia should be available during the exam for your child's safety. You will be told how to prepare your child. Some facilities may have personnel who work with children to help avoid the need for sedation or anesthesia. They may prepare children by showing them a model MRI scanner and playing the noises they might hear during the exam.
They also answer any questions and explain the procedure to relieve anxiety. Some facilities also provide goggles or headsets so the child can watch a movie during the exam. This helps the child stay still and allows for good quality images. The traditional MRI unit is a large cylinder-shaped tube surrounded by a circular magnet. You will lie on a table that slides into a tunnel towards the center of the magnet.
Some MRI units, called short-bore systems , are designed so that the magnet does not completely surround you.
Some newer MRI machines have a larger diameter bore, which can be more comfortable for larger patients or those with claustrophobia. They are especially helpful for examining larger patients or those with claustrophobia.
Open MRI units can provide high quality images for many types of exams. Open MRI may not be used for certain exams. For more information, consult your radiologist.
Instead, radio waves re-align hydrogen atoms that naturally exist within the body. This does not cause any chemical changes in the tissues. As the hydrogen atoms return to their usual alignment, they emit different amounts of energy depending on the type of tissue they are in.
The scanner captures this energy and creates a picture using this information. In most MRI units, the magnetic field is produced by passing an electric current through wire coils. Other coils are inside the machine and, in some cases, are placed around the part of the body being imaged.
These coils send and receive radio waves, producing signals that are detected by the machine. The electric current does not come into contact with the patient. A computer processes the signals and creates a series of images, each of which shows a thin slice of the body.
The radiologist can study these images from different angles. MRI is often able to tell the difference between diseased tissue and normal tissue better than x-ray, CT, and ultrasound. The technologist will position you on the moveable exam table. They may use straps and bolsters to help you stay still and maintain your position.
The technologist may place devices that contain coils capable of sending and receiving radio waves around or next to the area of the body under examination. MRI exams generally include multiple runs sequences , some of which may last several minutes. Each run will create a different set of noises.
If your exam uses a contrast material, a doctor, nurse, or technologist will insert an intravenous catheter IV line into a vein in your hand or arm. They will use this IV to inject the contrast material. You will be placed into the magnet of the MRI unit. The technologist will perform the exam while working at a computer outside of the room. You will be able to talk to the technologist via an intercom.
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