MAGNETIC-RESONANCE-IMAGING CAN CAUSE FOCAL HEATING IN A NONUNIFORM PHANTOM

被引:23
作者
DAVIS, PL [1 ]
SHANG, C [1 ]
TALAGALA, L [1 ]
PASCULLE, AW [1 ]
机构
[1] UNIV PITTSBURGH,MED CTR,DEPT MICROBIOL,PITTSBURGH,PA 15213
关键词
D O I
10.1109/10.250588
中图分类号
R318 [生物医学工程];
学科分类号
0831 ;
摘要
To test if the radiofrequency fields of a magnetic resonance imager could cause focal heating, two cylindrical phantoms were made from a mixture of agar and saline. The first phantom was uniform; the second was nonuniform in that a narrow bridge of agar was produced. Both phantoms were exposed to high levels of radiofrequency power (140 W) at 63 MHz and the tempature rises were measured. In the uniform phantom, the temperature increased as the radius increased. In the bridge phantom, the narrow bridge heated three times greater than at the opposite uniform periphery, and over five times the average of the uniform phantom. This experiment demonstrates that the radiofrequency fields of magnetic resonance imagers can cause focal heating if the exposed object is nonuniform. Since nonuniformity is present in the human body, as the radiofrequency power of magnetic resonance imaging techniques increases, focal heating in patients is a concern.
引用
收藏
页码:1324 / 1327
页数:4
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