Magnetic Resonance Imaging (MRI) is a non-invasive, powerful diagnostic tool that uses strong magnetic fields to obtain detailed pictures of the human body, causing no radiation exposure to the patient. MRI can be used in the diagnosis of many types of conditions, ranging from orthopedic to neurological, or fetal.  MRI is preferred in some cases because of its clearer images and ability to detect small defects.  MRI is much more sensitive to soft tissue, making it the modality of choice to evaluate ligament/tendon tears, the fine details of the brain, tumors, and vasculature.  The negative side of MRI is the length of the exams.  A CT scan can take a matter of seconds to minutes, while an MRI can take 50 minutes to a couple hours depending on the study.  MRI also cannot be used in patients with certain types of metal implants or pacemakers.  Its important to speak to your referring physician to determine if MRI is the right choice for you.