Common Uses of This ProcedureThe 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 also provides detailed images of the brain.
MRI can also provide high detail images of the abdomen - including the 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, hips, prostate and breast.
How does it work?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 five to ten imaging sequences, each lasting two to eight 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 and 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.
What You should Know
St. Rita’s has two (2) MRI systems designed with patient comfort in mind. The 1.5 Telsa MRI is a short bore magnet with a flared end tunnel to create a more comfortable atmosphere. This MRI has a 70cm opening accommodating 550 pounds.
St. Rita's is the only medical facility in the area with a short wide bore 1.5 Tesla scanner.
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 FM 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 sweat suit 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 or Coils
- A Pacemaker or Pacing Wires that are not MRI compatible
- Metal Fragments in One or Both Eyes
- Inner Ear Implants
- An Implanted Spinal Cord Stimulator, Brain Stimulator or Bladder Stimulator
After 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.