Magnetic Resonance Imaging is (MRI) is a noninvasive and painless medical test that healthcare providers use to diagnose and treat numerous medical conditions and injuries. MRI utilizes a powerful magnetic field, radio frequency pulses and a computer to produce detailed pictures of organs, soft tissues and bone. It does not use radiation (x-rays). The actual magnetic field is created by passing an electric current through specialized wire coils located within the MRI unit.
The organs, soft tissues and bones that are being imaged, send and receive radio waves, producing signals that are detected by the coils. A computer then processes these signals and generates a series of images, each of which shows a thin slice of the body. The images can then be studied from various angles by the interpreting radiologist. Some MRI exams may require you to receive an injection of contrast material. Gadolinium is most commonly used. It is injected into a vein by the technologist prior to the start of a study.
This type of contrast may be used in individuals with an allergy to iodine, but may require pre-medication. It is important to let your technologist know if you have had any recent surgeries or problems with your kidneys or liver. It is also important that women advise their technologist if there is a possibility that they are pregnant. If you suffer from claustrophobia (fear of enclosed spaces) or anxiety, you may want to ask your health care provider for a prescription for a mild sedative to be taken prior to your exam.
On the day of the exam, you may be asked to wear a gown. It is best to dress in comfortable clothing (without metal zippers). No jewelry or watches. Metal and electronic items (such as phones, pins, hairpins, glasses, pens, pocket knives etc.) are not allowed in the MRI scanning room because they will interfere with the magnetic field of the MRI unit. Also, no credit cards or hearing aids which could become damaged during the study. Body piercings and removable dental appliances must be removed before the exam.
Before the MRI exam is performed, you will be positioned on a moveable exam table. Straps may be used to help you stay still and maintain the correct position during imaging. The technologist will monitor the series of images at a computer workstation adjacent to the scanning room. They will be able to see, hear and speak with you at all times. Depending on the areas being scanned, your study can last anywhere from 30 min to an hour. It is very important that you lay perfectly still while the images are being obtained. You will know when images are being recorded because you will hear and feel loud tapping or thumping sounds when the coils that generate the radiofrequency pulses are activated.
Once all of the imaging sequences have been completed, a Board Certified Radiologist will review the images and provide written results to your referring provider, usually within 72 hours. A digital copy of the MRI study can be provided to your health care provider at no cost. Your referring provider will then review the results and a plan for treatment with you.