Vertical Sleeve Gastrectomy In a vertical sleeve gastrectomy, the surgeon creates a small, tube-shaped stomach by removing the greater portion of the stomach through keyhole incisions. The resulting pouch, about the shape and size of a banana, is larger than the pouch created during Roux-en-Y gastric bypass. By removing the outer aspect of the stomach, the majority of the cells that produce the hunger hormone grhelin are removed and patients feel less hungry. View a video of vertical sleeve gastrectomy › For more information or to request a consultation, call 888-717-GIMD (888-717-4463).