MRI

An MRI is a non-invasive medical test that helps doctors diagnose and treat medical conditions. Using a powerful magnetic field, radio frequency pulses and a computer, detailed pictures of organs, soft tissues, bone, or other internal body structures can be produced. These images are then examined on a computer screen and can be transmitted electronically, copied to a computer disc, or printed.

Unlike X-rays and CT scans, this form of imaging uses no ionized radiation. A circular magnet is contained in a large cylinder through which the patient, lying on a table, passes through. A strong magnetic field, produced by passing electric current through wire coils in the machine, sends and receives radio waves that are detected by the coils. There is almost no risk associated with this procedure. Images from an MRI are often better in distinguishing differences between abnormal or diseases tissue from normal tissue than those produced by other images such as X-rays, CT, or ultrasound.

To conduct the exam, the patient is positioned on a moveable examination table and must stay as still as possible. Once positioned, the patient is moved into the large cylindrical magnet of the MRI. As the images are recorded, the patient will hear the tapping/thumping of the coils within the machine. The procedure is painless, though it is normal for patients to experience a warming sensation in the area being imaged and to have difficulty remaining still. For patients that experience claustrophobia, sedation can be arranged. The entire exam is generally completed within 15 to 45 minutes.

Preparation for MRI exams vary. Some may require the patient to fast for 8-12 hours. Depending on the type of exam, the patient may also be required to swallow or receive an injection of contrast material, which aids the imaging process. Metal and electronic devices can interfere with the MRI exam and therefore must be removed before the exam. Patients should always consult their technologists about any medical or electronic implants.