What is MRI?
Magnetic resonance imaging, or MRI, uses strong magnet and radio waves to provide clear and detailed diagnostic images of internal body organs and tissues. MRI is a valuable tool for the diagnosis of a broad range of conditions, including:
- heart and vascular disease (cardiac MRI)
- joint and musculoskeletal disorders
MRI allows evaluation of many body structures that may not be as visible with other diagnostic imaging methods. One special feature of MRI is its ability to obtain views of the body from any angle or direction, so that complex anatomy can be demonstrated from the most revealing perspectives. Another characteristic of MRI is its ability to characterize fine differences amongst tissues, especially when gadolinium contrast is used.
What are some common uses of MRI?
Imaging of the Musculoskeletal System: MRI is often used to study the knee, ankle, foot, shoulder, elbow, wrist, and hand. MRI is also a highly accurate method for evaluation of soft tissue structures such as tendons and ligaments, which are seen in great detail. Even subtle injuries are easily detected. In addition, MRI is used for the diagnosis of spinal problems including disc herniation, spinal stenosis, and spinal tumors.
Imaging of the Heart and Blood Vessels: MRI of the heart, aorta, coronary arteries, and blood vessels is a tool for diagnosing coronary artery disease and other heart problems. MRI can look at damaged heart muscle with gadolinium contrast as well as quantify blood flow across intracardiac shunts. MRI can also image blood vessels without gadolinium contrast, which is extremely helpful in patients who have poor kidney function or who have severe allergies.
Imaging for Cancer & Functional Disorders: Organs of the chest and abdomen such as the liver, lungs, kidney, bowel and other abdominal organs can be examined in great detail with MRI. This aids in the diagnosis and evaluation of tumors and functional disorders. In the early diagnosis of breast cancer, MRI is an alternative to traditional x-ray mammography. Furthermore because there is no radiation exposure is involved, MRI is often used for examination of the male and female reproductive systems or to followup patients who need sequential imaging over months.
How should I prepare for an MRI?
- You may be asked not to eat or drink before the exam depending upon the body area to be examined. You will be asked to change into a gown. Before your MRI exam, remove all accessories including hair pins, jewelry, eyeglasses, hearing aids, wigs, dentures. During the exam, these metal objects may interfere with the magnetic field, affecting the quality of the MRI images taken. Occasionally, an x-ray of your body to look for metal.
- The technologist will ask you several specific questions to make sure
it is safe for you to enter the MRI machine room. Notify your technologist
if you have:
- any prosthetic joints – hip, knee
- a heart pacemaker (or artificial heart valve), defibrillator or artificial heart value
- an intrauterine device (IUD),
- any metal plates, pins, screws, or surgical staples in your body.
- tattoos and permanent make-up.
- a bullet or shrapnel in your body, or ever worked with metal.
- medication patches
- if you might be pregnant or suspect you may be pregnant.
- if you are claustrophobic. Some patients who undergo MRI in an enclosed unit may feel confined. If you are not easily reassured, a sedative may be administered.
What should I expect during this exam?
Depending on how many images are needed, the exam generally takes 15 to 45 minutes. However, very detailed studies may take longer.
- You must lie down on a sliding table and be comfortably positioned. The body area to be examined will be placed on a “coil,” a special type of MR antenna designed to capture the images we are generating.
- Even though the technologist must leave the room, you will be able to communicate with them at any time using an intercom.
- If necessary, a friend or family member may stay in the room with you during the exam.
- You will be asked remain still during the actual imaging process. However, between sequences, which last between 2-15 minutes, slight movement is allowed.
- Depending on the part of the body being examined, a contrast material may be used to enhance the visibility of certain tissues or blood vessels. A small needle is placed in your arm or hand vein and a saline solution IV drip will run through the intravenous line to prevent clotting. About two-thirds of the way through the exam, the contrast material is injected.
What will I experience during an MRI?
- MRI is painless.
- Some claustrophobic patients may experience a "closed in" feeling. If this is a concern, a sedative may be administered. Also, newer open MRI machines have helped to alleviate this reaction.
- You may hear loud tapping or thumping during the exam. Earplugs or earphones may be provided to you by the MRI center. For persons who are sensitive to noise, the Toshiba Titan MRI system at Abington Memorial Hospital has Pianissimo quiet technology which greatly reduces acoustic noise.
- You may feel warmth in the area being examined. This is normal.
- If a contrast injection is needed, there may be some discomfort at the injection site. You may also feel a cool sensation at the site during the injection.
What if I am claustrophobic or overweight?
- Open MRI at Blue Bell: Abington Health offers a special “OPEN” MRI located at the Blue Bell campus designed specifically to accommodate claustrophobic and overweight patients. Please call 215-481-EXAM (3926) to schedule your Open MRI appointment.
- Wide Bore MRI: The Toshiba Titan 1.5 Tesla wide bore field system at Abington Memorial Hospital allows many obese or claustrophobic patients the ability to be scanned on a high field system with increased comfort.
For more information on this topic, please visit www.Radiologyinfo.org.