Background : Rectal perception and adaptation to distension are widely heterogeneous in subjects with faecal incontinence.
Aim : To quantify rectal physiology in patients with incontinence and low maximum rectal volume, according to AGA guidelines on anorectal testing techniques.
Patients and methods : 148 patients (12 men, 136 female) with incontinence to liquid and/or solid stools were investigated. Distending isobaric procedures were carried out using an electronic barostat in order to analyse perception and adaptation of the rectum.
Results : Pain during isovolumic rectal distension at a level of 100 mL or less was experienced in 21 subjects (14.2%). As defined by isobaric distensions, incontinent patients with low MTV had more frequently a hypocompliant rectum (62%) when compared with those with higher MTV (31%, P = 0.046). Perception scores tended to be higher at each step of distending rectal pressure: incontinent patients with low MTV had more frequently a hypersensitive rectum (48%) when compared with those with normal or high MTV (24%, P = 0.035). Only four of 21 incontinent subjects with low MTV had an isolated hypersensitive rectum.
Conclusion : Both sensitivity and compliance are altered in patients with low MTV. A more extensive study of the role of sensory and compliance aspects of subjects with incontinence is warranted.