COMPUTER-SUPPORTED ANALYSIS OF CONTINUOUS AMBULATORY MANOMETRIC RECORDINGS IN THE HUMAN SMALL-BOWEL

An algorithm has been developed for the offline analysis of prolonged manometric recordings in the upper small intestine of humans. Sample d ata are acquired in the human duodenum and jejunum using six solid-sta te strain-gauge transducers mounted on a silicon catheter that is conn ected to a portable digital recording device. The data are sampled at 4 Hz and filtered. For accurate calculations, the filtered signals are converted to cubic B-spline functions of order four. Based on an expo nential weighted moving average, a base-line is calculated from the si gnal. Contractions are recognised on the basis of thresholds for minim um amplitude and duration. The developed algorithm calculates properti es of these contractions, such as amplitude, duration, area and a moti lity index. In addition, the program automatically recognises normal m otor patterns of the fasted human small intestine, such as the migrati ng motor complex, and aids in the identification of the postprandial m otor pattern. Motor patterns are defined in terms of properties such a s contraction frequency and propagation. In a validation procedure usi ng conventional manual analysis, the program correctly identifies the number of individual contractions with a 98% confidence interval and a lso correctly recognises 96% of phase 3 motor activity.