Biology: The Dynamics of Life, North Carolina EditionChapter 36: The Nervous SystemIn the NewsNobel Prize for Medicine Awarded Each year, the Nobel Prize is awarded in several categories. This year’s recipients in the field of medicine are Paul C. Lauterbur, USA and Sir Peter Mansfield, Briton. They will split a 1.3 million dollar prize. They were awarded the prize for their work with and discoveries of Magnetic Resonance Imaging (MRI). Lauterbur discovered that you could create a two-dimensional picture by introducing gradients in the magnetic field. When this is done, radio waves are emitted. Lauterbur found that he could determine the origin of the waves by analyzing their characteristics which made it possible to construct two-dimensional pictures of structures that could not be seen with other methods. Mansfield developed a method for analyzing the signals mathematically. This allowed developers to create a useful imaging technique. He also showed how the imaging could be done extremely fast. His work made it possible for an MRI device to be constructed that worked fast. How does an MRI scanner work? The scanner is made of a very strong magnet, usually a superconducting magnet, which sets up a magnetic field around the person being scanned. The magnetic field causes the hydrogen atoms in a person’s body to line up with the direction of the magnetic field. Then, a radio frequency pulse is applied toward the area of the body that is being examined. The pulse sends signals to the person’s body to upset the uniformity of the hydrogen atoms and receive return signals. This information is collected by a computer which analyzes it and produces the MRI image. An MRI scan can give detailed images of the brain, internal organs, and is often used to detect torn ligaments in knees, wrists, and ankles. Perhaps you know of someone who has had an MRI scan for this reason. It also can detect tumors in bones or soft tissue, diagnose strokes, and help doctors visualize injuries to many parts of the body. Activity Resources |  |
