Pouch outlet obstruction following vertical ring gastroplasty for morbid obesity. We have experienced a 14% (38 of 264 patients) incidence of pouch outlet obstruction following vertical ring gastroplasty. Initial management consisted of dilatation in 34 of 38 patients (94%). Ten of 34 patients (29%) were spared reoperation by 1 to 3 dilatations. Non-passage of an endoscope through the stoma immediately following dilatation predicted the need for surgery; 4 of 11 patients (36%) with passage underwent reoperation compared with 17 of 20 patients (85%) without passage (p less than 0.02). Surgical findings included "tipped bands" in 9 of 28 patients (32%); fibrous reaction to the band in 10 of 28 patients (36%); adhesions with angulation of the pouch in 2 of 28 patients (7%); and no identifiable cause of obstruction in 7 of 28 patients (25%). Surgical therapy consisted of removal of the band (2 patients), removal of the band and replacement with a similar length or larger band (20 patients), "tacking" the band in the horizontal position (4 patients), or conversion to a Roux-Y bypass (2 patients). The first three options were associated with an unacceptably high rate of weight regain and/or continued symptoms, whereas the last-named procedure met with good success. 