title: Cap Assisted Upper Endoscopy for Examination of the Major Duodenal Papilla: A Randomized, Blinded, Controlled Crossover Study (CAPPA Study).
abstract: Examination of major duodenal papilla (MDP) by standard forward-viewing esophagogastroduodenoscopy (S-EGD) is limited. Cap assisted esophagogastroduodenoscopy (CA-EGD) utilizes a cap fitted to the tip of the endoscope that can depress the mucosal folds and thus might improve visualization of MDP. The aim of this study was to compare CA-EGD to S-EGD for complete examination of the MDP.
  
  
  
  Prospective, randomized, blinded, controlled crossover study. Subjects scheduled for elective EGD were randomized to undergo S-EGD (group A) or CA-EGD (group B) before undergoing a second examination by the alternate method. Images of the MDP were evaluated by three blinded multicenter-experts. Our primary outcome measure was complete examination of the papilla. Secondary outcome measures were duration and overall diagnostic yield.
  
  
  
  A total of 101 patients were randomized and completed the study. Complete examination of MDP was achieved in 98 patients using CA-EGD compared to 24 patients using S-EGD (97 vs. 24%, P<0.001). Median duration from intubation of the esophagus until localization of the MDP was shorter with CA-EGD (46. vs. 96 s., P<0.001). In group A, 11 extra lesions and 12 additional incidental findings were detected by secondary CA-EGD, whereas neither were detected by secondary S-EGD in group B (22 vs. 0% and 24 vs. 0%, P<0.001 and P<0.001).
  
  
  
  CA-EGD enabled complete examination of MDP in almost all cases compared to a low success rate of S-EGD. CA-EGD detected a significant amount of lesions and incidental findings when added to S-EGD. CA-EGD is a safe and effective method for examination of MDP.
authors.affiliation: II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Abdelhafez
authors.affiliation: II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Veit
authors.initials: V
authors.lastname: Phillip
authors.affiliation: Institut fìr Medizinische Statistik und Epidemiologie, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Hapfelmeier
authors.affiliation: II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.|Department of Infectious Diseases and Endemic Hepatology and Gastroenterology, Kasr Alainy Hospital, Cairo University, Cairo, Egypt.
authors.forename: Mayada
authors.initials: M
authors.lastname: Elnegouly
authors.affiliation: II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Poszler
authors.affiliation: II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Kilian
authors.initials: K
authors.lastname: Strobel
authors.affiliation: Innere Medizin II-Gastroenterologie, Rotkreuzklinikum, Munich, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Born
authors.affiliation: Klinik fìr Gastroenterologie und Hepatologie, Klinikum Neuperlach, Munich, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Dollhopf
authors.affiliation: Department of Infectious Diseases and Endemic Hepatology and Gastroenterology, Kasr Alainy Hospital, Cairo University, Cairo, Egypt.
authors.forename: Abdel Meguid
authors.initials: AM
authors.lastname: Kassem
authors.affiliation: Klinik und Poliklinik fìr Chirurgie, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Lenika
authors.initials: L
authors.lastname: Calavrezos
authors.affiliation: II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Klare
authors.affiliation: II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Schlag
authors.affiliation: II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Monther
authors.initials: M
authors.lastname: Bajbouj
authors.affiliation: II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Roland M
authors.initials: RM
authors.lastname: Schmid
authors.affiliation: II. Medizinische Klinik und Poliklinik, Klinikum rechts der Isar der Technischen Universität Mìnchen, Munich, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: von Delius
mesh_terms: D000328:Adult; D014670:Ampulla of Vater / Q000000981:diagnostic imaging*; D002983:Clinical Competence; D018592:Cross-Over Studies; D016099:Endoscopy, Gastrointestinal / Q000295:instrumentation*; D005260:Female; D005767:Gastrointestinal Diseases / Q000000981:diagnostic imaging*; D006801:Humans; D033162:Incidental Findings; D008297:Male; D008875:Middle Aged; D061646:Operative Time; D011446:Prospective Studies; D016037:Single-Blind Method