Reply to Boškoski et al.

We appreciate the author’s interest in our publication [1]. We agree that endoscopic retrograde cholangiopancreatography (ERCP) is one of the most difficult endoscopic disciplines to learn. Indeed, until now, in most places of the world, learning and training of ERCP have been done on humans; however, we strongly believe that training should be first accomplished using ERCP models, ideally ex vivo biologic models that allow for therapeutic interventions, including sphincterotomy [2] [3] [4] [5]. In order to provide better training before embarking on “human training,” several models have been developed for ERCP training, including live animals (e. g. pigs and dogs), and ex vivo biologic and plastic models such as those shown in [Fig. 1] and [Fig. 2] [1] [2] [3] [4] [5].

Fig. 1 Four-step approach to endoscopic retrograde cholangiopancreatography (ERCP) training as proposed by the International ERCP Model Working Group. a A simple plastic tube is encased in foam to protect the scope from damage while the trainee learns wheel handling. b Vacuum cleaner tubing is useful to mimic the duodenum. c Foam protects the scope from damage. d Biliary sphincterotomy is best learned using biologic tissue, such as chicken hearts. The image shows a pig stomach with “papilla” (chicken heart) on the lesser curvature. e Suturing the “papilla” (chicken heart). f The chicken heart mimics the papilla. g Endoscopic view of the chicken heart (“papilla”). h Hands-on ERCP model, developed by Prof. N. Rustemovic and made from fiber glass used in boat repair.

Fig. 2 The model developed by Prof. M. D’Assunção (MADA model) uses mannequins.

The design of the ERCP Trainer (Cook Medical, Limerick, Ireland) by the authors appears promising. However, until now, no study describing or evaluating this training device had been published. Indeed, in the United States, this model only recently became available from Cook Medical (Winston-Salem, North Carolina, USA) [6]. This lack of evaluation was our motivation for investigating and testing the model. We feel that the video and initial validation may encourage other authors to evaluate the ERCP Trainer and other ERCP training models. We continue to perform extensive validations on this and other ERCP models, including several developed by our International ERCP Training Working Group ([Fig. 1], [Fig. 2]).

Although some authors believe that training for ERCP may be accomplished using only one model, we strongly believe that several models should be used, in a stepwise approach. Thus, our group uses a four-model approach to train endoscopists: i) start with a tube to hold the duodenoscope and to learn how to handle the wheels of the scope ([Fig. 1a, b]); ii) learn three-dimensional manual-cognitive aspects of scope position and cannulation using plastic models ([Fig. 1]) or an ex vivo biologic model such as the MADA ([Fig. 2]) or Erlangen Endo-Trainer [2]; iii) learn sphincterotomy in an ex vivo biologic training model, such as the models developed by Prof. Neumann, Velázquez-Aviña et al., or Prof. Rustemovic ([Fig. 1]) [2] [3] [4]; and iv) learn precut sphincterotomy using tissue that mimics papillae, such as chicken hearts attached to a pig stomach ([Fig. 1 d – g]) [3] [4].

In summary, the ERCP Trainer may become another addition to the myriad of ERCP models currently available to train pancreaticobiliary endoscopists. However, we fully agree with the authors that further trials are necessary to demonstrate the potential usefulness of this ERCP trainer and to compare it with other widely established and well-validated ERCP models.

• References

• 1 Jovanovic I, Fry LC, Rustemovic N et al. Initial validation of a simple, nonbiological, mechanical ERCP training model for cannulation and stent placement. Endoscopy 2015; 47: E585-586
• 2 Neumann M, Mayer G, Ell C et al. The Erlangen Endo-Trainer: life-like simulation for diagnostic and interventional endoscopic retrograde cholangiography. Endoscopy 2000; 32: 906-910
• 3 Velázquez-Aviña J, Sobrino-Cossío S, Chávez-Vargas C et al. Development of a novel and simple ex vivo biologic ERCP training model. Gastrointest Endosc 2014; 80: 1161-1167
• 4 Rustemovic N, D’Assunçao M, Bilic B et al. A simple ex vivo, biologic ERCP training model for sphincterotomy. Endoscopy 2015; 47: E401-403
• 5 Frimberger E, von Delius S, Rösch T et al. A novel and practicable ERCP training system with simulated fluoroscopy. Endoscopy 2008; 40: 517-520
• 6 Cook Medical. Skills theatre: focus on ERCP fundamentals. Presented at 2015 Digestive Disease Week.. 2015 May 17 – 18, Washington DC. https://www.cookmedical.com/endoscopy/skills-theatre-focus-on-ercp-fundamentals/