Magnetic resonance imaging (MRI) is a diagnostic tool that uses a magnetic field and radio waves to produce finely detailed images of tissues of the body. MRI gives different information about structures in the body than can be seen with an X-ray, ultrasound, or computed tomography (CT) scan. MRI may be used to help evaluate bone and joint disorders e.g. arthritis, cartilage injuries, bone and joint infections and tumors.
MRI machines are large tubes with a large magnet. When the patient lies inside the machine, the magnet temporarily realigns hydrogen atoms in the body. Radio waves cause these aligned atoms to produce signals, which are received by sensors. A computer then processes the signals and generates a series of images, each of which shows a thin slice of the body or a 3D image of it. These images can then be studied from different angles by the radiologist.
The MRI is very safe with no ionizing radiation involved. A typical MRI scan will take 20-30 minutes.
Because the MRI machine contains a strong magnet, the presence of metal in your body may be a hazard and may affect the quality of the MRI image. Before having an MRI, tell the doctor if you have any metal or electronic devices in your body, such as metallic plates, screws and nails, joint prostheses, artificial heart valves, pacemaker, metal clips ….
Also, Inform your doctor about any kidney or liver problems that you have as this may hinder the use of injected contrast agents during your scan.