Treatment of ring slippage after gastric bypass: long-term results after endoscopic dilation with an achalasia balloon (with videos) - Campos, Josemberg Marins; Evangelista, Luis Fernando; Ferraz, Álvaro Antônio B; Galvão Neto, Manoel P; Moura, Eduardo Guimarães H. de; Sakai, Paulo; Ferraz, Edmundo M (Gastrointestinal endoscopy, 2010)