Non-invasive electrocologram: non-invasive recording of the human colonic electrical activity.

The electrical activity of the descending colon of fifteen healthy volunteers was recorded non-invasively by cutaneous electrodes sticked on the abdominal wall along the descending colon projection--electrocologram (EColG). The electrical activity of the colon and stomach was recorded by an original electrogastrograph. The means, S.E.M. of the frequency of the colonic and gastric waves were calculated. Parallel studies of the EColG and the changes in the intracolonic pressure were performed on 10 patients with balloon inflated in the colon. Two kinds of EColG waves according to their frequency were identified: i) Type A waves with a frequency of 5.86 +/- 0.59 cpm and ii) Type B waves with a frequency of 2.35 +/- 0.25 cpm. There was a significant difference between the frequencies of the EColG waves and the frequency of the EGG waves -3.35 +/- 0.31 cpm. The type A waves were of low amplitude and corresponded to type A dog colonic waves i.e. they characterized the quiescent period of colonic motility. Type B waves were with a high amplitude, corresponded to type B dog colonic waves and characterised the activity periods of colonic motility. This was confirmed by the correspondence between type B waves and the changes in the intracolonic pressure. Thus the proposed non-invasive electrogastrographic method proved to be suitable for non-invasive registration of the electrical activity of the human colon.