15 Facts You Need to Know About MRI
- MRI stands for Magnetic Resonance Imaging.
- An MRI can be used to take images of the brain and face, spine, joints, long bones, vascular systems, abdomen and lungs.
- Many different diseases that are treatable and even curable can be definitively diagnosed using MRI.
- The MRI scanner is a superconducting electro magnet that is filled with approximately 1,000 liters of liquid helium, which exists at a temperature of four degrees Kelvin (-452 degrees Fahrenheit).
- The MRI’s magnetic field is 1,000–4,000 times stronger than the earth’s magnetic field. Magnetism is measured in Gauss, while MRI scanners are measured in Tesla. 1 Tesla = 10,000 Gauss. VIoC's scanner is 1.5 Tesla.
- The scanner utilizes its powerful magnetic field, radio-frequency pulses and computer to produce detailed pictures of internal body structures.
- The strong magnetic field in the MRI scanner is used to align hydrogen protons in tissue.
- MRI is able to make such clear pictures because of the large number of protons found in the body, primarily in water and fat.
- Radio waves are used to affect hydrogen protons in specific interactions. The radio frequency receptors then collect the response or “echo” of the protons.
- Unhealthy tissues respond to the radio frequencies differently than healthy tissues.
- Advanced computer systems evaluate and reconstruct the data into images. Each image sequence gives a unique set of information. MRI provides superior images with excellent soft-tissue detail and three-dimensional reconstruction.
- Imaging can be done at practically any position or angle without moving the patient.
- Since the information the MRI produces is digital, the scans can be sent in real time to our board-certified radiologist and to the referring veterinarian.
- Unlike conventional radiographs (x-rays) or computerized tomography (CT), MRI does not use ionizing radiation, which can be harmful. (X-rays are a trillion times more energetic and potentially damaging than radio waves.)
- MRI contrast agents do not cause the allergic reactions that iodine-based agents do.
For more on the technology of MRI, see
Thanks to Kevin C. Stevens, ARRT, RT (R)(MR), VIoC's Chief of Imaging, for assistance in putting this list together.