Pull-through endoscopic vacuum-assisted closure therapy for complicated leaks of the gastrointestinal tract: Novel technique - Carsten Engelke; Yaser Hatem; Carlos Maaß; Martin Kraus; Michael Thomaschewski; Fabian Jacob; Roman Kloeckner; Malte Maria Sieren; Tobias Keck; Jens U Marquardt; Jens Hoeppner; Martha Maria Kirstein (Endoscopy International Open)