PURPOSE: A hypertonic, electrically hyperactive segment has been described in the rectosigmoid region mainly in constipated persons. Anatomic or manometric evidence to satisfy the criteria for a sphincter here is, however, inconclusive. We evaluated the pressure profile of the rectosigmoid region in normal Indian men. METHODS: Fifteen male volunteers with regular bowel habits were studied. Rectosigmoid manometry (1 cm station pull-through) was done in the fasting state using a water-perfused system and three-lumen catheter with radially oriented recording ports 5 cm apart. RESULTS: Eight volunteers had a zone of high pressure. Proximal extent of this zone was identified as the station with a rise in basal pressure of at least 10 mmHg over the previous station. A further rise of at least 10 mmHg in subsequent distal stations was considered essential for defining the existence of the zone. This zone had a median length of 3 cm, with midpoint at median 18 cm from the anal verge and median highest pressure of 36 mmHg. There was no antegrade pressure gradient across the zone; rectal pressures were higher than those in the sigmoid in 12 of 15 volunteers. CONCLUSIONS: Approximately one-half of normal Indian men with regular bowel habits have a high pressure zone in the rectosigmoid region. The role of diet or defecation posture in its etiology and its effect on bowel habit need to be studied.
PURPOSE: A hypertonic, electrically hyperactive segment has been described in the rectosigmoid region mainly in constipatedpersons. Anatomic or manometric evidence to satisfy the criteria for a sphincter here is, however, inconclusive. We evaluated the pressure profile of the rectosigmoid region in normal Indian men. METHODS: Fifteen male volunteers with regular bowel habits were studied. Rectosigmoid manometry (1 cm station pull-through) was done in the fasting state using a water-perfused system and three-lumen catheter with radially oriented recording ports 5 cm apart. RESULTS: Eight volunteers had a zone of high pressure. Proximal extent of this zone was identified as the station with a rise in basal pressure of at least 10 mmHg over the previous station. A further rise of at least 10 mmHg in subsequent distal stations was considered essential for defining the existence of the zone. This zone had a median length of 3 cm, with midpoint at median 18 cm from the anal verge and median highest pressure of 36 mmHg. There was no antegrade pressure gradient across the zone; rectal pressures were higher than those in the sigmoid in 12 of 15 volunteers. CONCLUSIONS: Approximately one-half of normal Indian men with regular bowel habits have a high pressure zone in the rectosigmoid region. The role of diet or defecation posture in its etiology and its effect on bowel habit need to be studied.