A computed tomography, or CT scan, uses X-rays, a form of radiation, to capture images of internal body structures and organs, states WebMD. Magnetic resonance imaging, or an MRI test, uses a magnetic field and pulses of radio wave energy; it typically offers more detailed information than a CT scan.Continue Reading
MRI often reveals problems in the body that are not visible with other imaging methods, according to WebMD. The patient lies on a table that slides into the large imaging machine containing the strong magnet, often with straps restraining the upper body from moving. Breathing or heartbeat may be monitored by a special belt that prompts the scanner to capture the images at the right time. The digital images are sent to a computer where they can be stored and analyzed both on-site and remotely. Contrast material, or dye, may be injected or swallowed by the patient to allow structures to be more visible in the pictures.
During a CT scan, the patient lies on a table attached to the large, doughnut-shaped imaging machine that rotates, capturing small segments of the organ or structure being assessed, explains WebMD. The images are saved on a computer and may also be printed. Intravenous contrast material may be used in the arm, inserted into the rectum or a joint, or taken by mouth.Learn more about Diagnostics & Imaging