Evaluation of computerized analysis of the propagation of human duodenojejunal contractions

Abstract

Detection of peristalsis in the human small intestine has been limited in the past by both the available measurement techniques and the complexity of this activity. Recent developments in ambulant recording have provided a means of monitoring the occurrence of intestinal contractions at multiple sites in the small bowel, but the problem of complexity remains. Using digital data recorded from an intra‐luminal strain‐gauge transducer in the proximal gut, an algorithm was implemented to identify and classify contractile events within the small bowel. By modelling propagated activity the effect of varying transducer spacing and the number of transducers used was assessed. The question of variability of apparent velocity of peristaltic contractions was examined using successive cross‐correlation calculations to extract underlying phase differences between samples of 512 minutes of manometric recording over 150 mm of human small bowel. The effective velocity was found to have a median value of 14 mm sec‐1 and an inter quartile range of 12–18 mm see‐1). It is proposed that, in dynamically tracking variations in phase difference between adjacent recording sites, cross‐correlation techniques should be used to control the parameters used for the recognition of propagated contractile events and thereby improve the specificity of this process.

The nocturnal jejunal migrating motor complex: defining normal ranges by study of 51 healthy adult volunteers and meta‐analysis

“…For each subject, the nocturnal period was based on diary entries. Automated analysis was initially performed using a program for the identification of small bowel contractile events that has been developed and validated in Centre 1 18,19 . A pressure event that exceeded a threshold of 10 mmHg, for which there was no simultaneous event occurring in the other two channels, was assessed by the algorithm as being the consequence of an enteric contraction.…”

Small Bowel Motor Activity in Response to Physiological Meals of Different Chemical Composition in Man

“…phase III was ignored if it appeared within 20 minutes after the ingestion of the test meal, as conversion of the interdigestive to postprandial motor pattern is not necessarily an immediate process [1,12]. A validated computer program calculated incidence and amplitude of contractions, as described previously [13,14]. The percentage of propagated contractions was calculated using the three pressure sensors at 27.5, 30 and 32.5 cm from the tip of the catheter [13,14].…”

“…A validated computer program calculated incidence and amplitude of contractions, as described previously [13,14]. The percentage of propagated contractions was calculated using the three pressure sensors at 27.5, 30 and 32.5 cm from the tip of the catheter [13,14]. These calculations were done for the total period between start of ingestion and the appearance of the next phase III and also for consecutive 30-minute periods thereof.…”