Endoscopic vacuum treatment (EVT) is increasingly used in the treatment of anastomotic leakages and perforations in the upper gastrointestinal tract. However, sponges often have to be mounted individually on a gastric tube and endoscopic introduction of the latter into an infected extraluminal cavity is challenging. In order to facilitate this procedure in some anatomical situations, we developed the prototype of a new sponge for EVT called a two-side sponge (TSS).