An inanimate ex-vivo pig stomach training model to acquire ESD skills

By Richard Whelan 6 Videos FEATURING Richard Whelan

34 views

January 2, 2019

Purpose/Background: Endoscopic Submucosal Dissection (ESD) allows for en bloc removal of large sessile lesions. It ...
read more ↘ is the gold standard in Japan for large sessile adenomas and sm-1 superficial cancers. In the US these lesions are usually treated via segmental colectomy. To avoid colectomy, some American surgeons are learning ESD methods in which a needle knife is used to score the mucosa and to cut the polyp’s submucosal attachments. This requires moving the scope tip with a knife extended and the current running. This is a skill that most endoscopists do not have.
To acquire these skills and learn ESD an ex vivo pig stomach training model has been developed. This video is devoted mainly to presenting the model and a few preliminary results.

Methods/Interventions: The colon model consists of a hard hollow plastic tube with a rectangular window cutout over which a full thickness piece of pig stomach and then a bovey pad is placed and secured with rubber bands. The tube is attached to a flat plastic board to anchor it. The bovey pad is inserted into a high frequency electrosurgical generator. A round sponge with a central slit is placed in the tubes end and serves as the “anus”. Prior to being placed in the model a hot wire loop is used to brand “the lesion” onto the mucosal surface. An ESD is then carried out using the standard instruments including: sclerotherapy catheter and saline lift solution (mucosal lift), needle knifes (straight, hook, etc), and dissection cap on endoscope tip. The ESD steps are: saline lift, superficial marking of resection line, mucosal scoring, undermining of cut mucosal edge, insertion of scope tip/cap into the submucosal pocket, cutting of submucosal attachments, further mucosal scoring and polyp detachment until done. The excision time, margins, number of partial and full thickness injuries, and number of reinjections necessary to maintain lift were tracked.

Results/Outcome(s): A total of 30 ESD’ have been performed by 2 surgeons. All have been successfully completed. The time required to complete the ESD ranged from 22 minutes to 111 minutes. The time variation is thought to be a function of tissue quality, ability to sustain mucosal lift and good conductivity as well as the skill of the endoscopist. A general downward trend in the number of partial and full thickness bowel wall injuries have been noted with time.

Conclusions/Discussion: This model has drawbacks but allows trainees to learn and carry out the basic ESD steps. It is best used with other models such as the bovine rectum/colon model which requires insufflation and a pattern tracing scope tip control training model. It is believed that this type of training when coupled with periodic practice session will allow surgeons with a moderate volume of large sessile colonic neoplasms to perform ESD successfully in the clinical setting.
↖ read less

0 Comments

Login

Login

Join VuMedi

An inanimate ex-vivo pig stomach training model to acquire ESD skills

Related Content