Effect of brain-stem lesion on colonic and anorectal motility. Study of three patients.

The supraspinal control of colonic motility and anorectal motility is poorly documented. We had the opportunity to study colonic function, esophageal function, and urinary bladder function in three patients who presented with vascular lesions limited to the anterior (case 1) or the posterior area (cases 2 and 3) of the pons. Esophageal manometry, urodynamic examination, whole and segmental transit time measurements (using radiopaque markers) and anorectal motility were systematically performed. The results were the following: (1) in the first case esophageal motility was not altered, whereas abnormal micturition, right colonic inertia, and absence of rectoanal inhibitor reflex were observed; (2) in cases 2 and 3, there was a poor esophageal coordination, the micturition and rectoanal inhibitor reflex were normal, and the transit time of the left colon was increased. Our observations are consistent with the previously described localization of neurological areas controlling swallowing and micturition; they also favor the pons as the possible level of supraspinal control of colonic and anorectal motility.