Nineteen patients with chronic idiopathic constipation, 8 patients with fecal incontinence, and 11 normal controls were studied with techniques of mucosal electrosensitivity and rectal balloon distension, and with electrophysiologic tests for the pudendal nerve terminal motor latency (PNTML). The results were as follows;
1) Balloon distension in the rectum revealed an elevated trend of minimal sensory volume in patients with constipation or incontinence, compared with controls (p=0.086) and significantly decreased in maximal tolerable volume in patients with incontinence (p<0.05). The urgency volume was similar in the three groups.
2) The PNTML were significantly raised in patients with incontinence, compared with controls (p<0.05).
3) Rectal mucosal electrosensitivity demonstrated an elevated trend of sensory threshod in patients with constipation or incontinence, compared with controls (p=0.1587). The anal electrosensitivity disclosed a sensory deficit in the anal canal in patients with incontinence, compared with patients with constipation or controls. This study shows the presence of a rectal sensory impairments in some patients with chronic idiopathic constipation and sensory deficit of the anal canal occurs in combination with the motor neuropathy in patients with idiopathic fecal incontinence.