The ability to noninvasively measure small bowel electric activity is of great importance in clinical settings. Intestinal ischemia is an emergent condition associated with a relatively high mortality rate partially due to the fact that no technique for noninvasive evaluation of small bowel viability is available. SQUID magnetometers are able to measure external magnetic fields that arise from current sources located inside the abdomen. Cutaneous electrodes placed on the abdominal surface may not detect intestinal electric activity since insulating layers of fat attenuate the electric signals. Magnetic fields are not as affected by insulators as electric fields and so magnetometry may be the only method for noninvasive measurement of small bowel electric activity. This project will evaluate the general application of SQUID magnetometry to the measurement of small intestinal electric activity and the specific application of a new specially-designed magnetometer to obtain increased spatial information in small intestine magnetic fields. Comparisons of SQUID magnetometry with electrical techniques will also be performed experimentally and theoretically using mathematical models.
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