MRI provides glimpse into ancient bones.MRI provides glimpse into ancient bones For the first time, scientists have used magnetic resonance imaging magnetic resonance imaging (MRI), noninvasive diagnostic technique that uses nuclear magnetic resonance to produce cross-sectional images of organs and other internal body structures. (MRI) to probe fossil remains, paving the way for in-depth studies of bone diseases that afflicted ancient animals. "It's a technique that I think can be useful in the future because you can see internal structures without cutting the bone to pieces," says radiologist Jeno I. Sebes of the University of Tennessee The University of Tennessee (UT), sometimes called the University of Tennessee at Knoxville (UT Knoxville or UTK), is the flagship institution of the statewide land-grant University of Tennessee public university system in the American state of Tennessee. in Memphis. He described the work last week at the annual meeting of the Society of Vertebrate Paleontology The Society of Vertebrate Paleontology was founded in 1940 for individuals with an interest in vertebrate paleontology. SVP (as it is known to its members) now has almost 2,000 members. in Lawrence, Kan. In the MRI procedure, a strong magnet aligns the spin axes of all free protons in a subject. As the protons return to their normal, random orientations, detectors monitor the radio waves they emit, providing three-dimensional data about the structure of bone and other tissue. In contrast, X-ray techniques such as CAT scanning do not penetrate well through the thick, rock-hard fossil bones of large animals. Sebes and his colleagues turned to MRI to examine the 12-million-year-old vertebrae of a dolphin. Because fossilized fos·sil·ize v. fos·sil·ized, fos·sil·iz·ing, fos·sil·iz·es v.tr. 1. To convert into a fossil. 2. To make outmoded or inflexible with time; antiquate. v.intr. bone contains few free protons, the researchers had to soak the vertebrae in water for 45 minutes. The resulting images revealed interior bands of thickened bone along the length of the vertebrae. Physicians who have observed similar bands in human bones have interpreted them as signs of arrested bone growth and have proposed a number of possible causes, including scurvy scurvy, deficiency disorder resulting from a lack of vitamin C (ascorbic acid) in the diet. Scurvy does not occur in most animals because they can synthesize their own vitamin C, but humans, other primates, guinea pigs, and a few other species lack an enzyme , heavy metal poisoning Heavy Metal Poisoning Definition Heavy metal poisoning is the toxic accumulation of heavy metals in the soft tissues of the body. Description , hyper-thyroidism and rickets rickets or rachitis (rəkī`tĭs), bone disease caused by a deficiency of vitamin D or calcium. Essential in regulating calcium and phosphorus absorption by the body, vitamin D can be formed in the skin by ultraviolet . Sebes suspects that such bands instead reflect normal periods of accelerated bone growth. MRI can help paleontologists identify a variety of bone tumors and arthritic changes that affected extinct animals, he says. The new approach poses several practical problems, however. Many fossils may be too fragile to withstand the necessary immersion in liquid, and the technique's current expense would prohibit widespread paleontological use, Sebes notes. His group is now testing MRI fossil probes using less expensive magnets. |
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