Methods for automatic detection of peristaltic waves in the small intestine

Methods have been developed to detect peristaltic waves that carry radioactive technetium-99m mebrofenin excreted in the bile through the upper intestinal tract. A dynamic study is processed sequentially to determine the region of interest in the intestine, ROI1, where the activity appears earliest. Mathematical correlation is calculated between the time-activity curves for all pixels exceeding a threshold, excluding those belonging to the liver and ROI1, and the time-activity curve for ROI1. Pixels with maximum correlation at the same time shift are assumed to belong to the same region of the intestine. Thus, for increasing time shifts, a consecutive series of ROIs are formed. The computer then builds an image (peristaltogram) where each line contains the counts versus time variation for an ROI, and the sequence of lines corresponds to the sequence of ROIs. Based on template matching, the periods of the peristaltic contractions in the small intestine may be determined. A case study demonstrates that peristaltic waves easily may be recognized and characterized.