Magnetic Resonance Imaging (MRI or MR) is one of the safest, most comfortable imaging techniques available. Detailed pictures of organs and tissues are produced using radio waves, a powerful magnet and an advanced computer system. A variety of medical conditions can be diagnosed through the highly accurate MRI pictures.
St. Rita 's has both high-field (closed) and low field (open) MRI available to you. High-field MRI produces the highest quality image in the shortest time allowing for the most accurate diagnosis. Because of its superior quality, high-field MRI should be your first choice whenever possible. For severely claustrophobic or large patients, open MRI offers a good alternative.
The clear pictures of soft-tissue structures near and around bones produced by MRI make it an excellent exam for spinal and joint problems. MRI is widely used to diagnose knee, shoulder, hip, elbow and wrist injuries, which are often sports-related injuries. Very small tears and injuries to ligaments and muscles can be seen through MRI exams.
MRI of the heart, aorta, coronary arteries and blood vessels is a fast, non-invasive tool for diagnosing coronary artery disease and heart problems. Physicians can determine the extent of damage caused by a heart attack or progressive heart disease by examining the size and thickness of the chambers of the heart.
MRI can also provide high detail images of the organs of the chest and abdomen - including the lungs, liver, kidney, spleen, pancreas and abdominal vessels. This helps in the diagnosis and evaluation of tumors and functional disorders. Because no radiation exposure is involved, MRI is often the preferred diagnostic tool for examination of the male and female reproductive systems, bladder, pelvis and hips.
MRI is a unique because, unlike the usual x-rays, radioisotope studies, and even CT scanning, it does not rely on ionizing radiation. Instead, radio waves are directed at protons, the nuclei of hydrogen atoms, in a strong magnetic field. Radio signals are produced and then computer-processed to form an image. In the body, protons are most abundant in the hydrogen atoms of water -- the "H" of H 2 O -- so that an MRI image shows differences in the water content and distribution in various body tissues. Even different types of tissue within the same organ, such as the gray and white matter of the brain, can easily be distinguished. An MRI exam is usually two to six imaging sequences, each lasting two to 15 minutes. Each sequence has its own degree of contrast and shows a cross section of the body in one of several planes (right to left, front to back, upper to lower).
Benefits of MRI imaging include:
- Images of the soft-tissue structures of the body, such as the heart, lungs, liver and other organs, are clearer and more detailed than with other imaging methods.
- MRI images can help physicians evaluate the function as well as the structure of many organs.
- The detail of MRI images makes MRI an excellent tool in early diagnosis and evaluation of tumors.
- MRI contrast material is less likely to produce an allergic reaction than the iodine-based materials used for conventional x-rays and CT scanning.
- MRI can detect abnormalities that might be hidden by bone with other imaging methods.
- MRI is a fast, non-invasive alternative to x-ray angiography for diagnosing heart and cardiovascular system disorders.
- There is no exposure to radiation with MRI.
Few risks of MRI imaging include:
- An undetected metal implant may be affected by the strong magnetic field.
- MRI is generally avoided in the first 12 weeks of pregnancy. Other imaging methods, such as ultrasound, may be advised for pregnant women.
The St. Rita's MRI system is designed with patient comfort in mind. It's a scanner with an open style magnet that has no "tunnel effect". This allows the ability to accommodate large and claustrophobic patients who cannot be scanned in other systems.
During the exam, the patient may be injected with an image enhancement agent, which in some conditions, helps to provide additional information. Music is available through headphones during the exam. Patients may choose one of their favorite radio stations to listen to. The exam takes between 15 and 60 minutes depending on the type of information needed.
There is no special preparation for an MRI exam. The patient should wear comfortable clothing such as a sweatsuit without metal snaps or zippers. Gowns are available if needed. Hairpins should not be worn. No jewelry or watches should be worn into the scan room.
A MRI exam is safe, simple, and painless. However, because some metal interferes with the MRI machine, a patient cannot be examined if they have:
- Brain Aneurysm Clips
- A Pacemaker or Pacing Wires
- Metal Fragments in One or Both Eyes
- Inner Ear Implants
- An Implanted Spinal Cord Stimulator or Brain Stimulator
- Shrapnel
A fter the test, because there are no side effects, the patient may leave immediately following the exam.
At St. Rita's we have a board certified radiologist on site daily so the test will be interpreted promptly. The results will be phoned, faxed, mailed, or delivered electronically to the referring physician. He/she will share the results with the patient.
