Evaluation of two liver biopsy and rectal sealing techniques in dog cadavers undergoing Natural Orifices Transluminal Endoscopic Surgery (NOTES) by transrectal access

Abstract

The aim of this study was to evaluate two liver biopsy techniques by transrectal Natural Orifice Transluminal Endoscopic Surgery (NOTES) and compare tensiometric parameters of rectal sealing using 2-octyl cyanoacrylate glue or conventional rectal sutures in a dog cadaver model. In sixteen dog cadavers two liver biopsy techniques were performed via transrectal NOTES using either polypectomy diathermy forceps or endoscopic oval biopsy forceps. The cadavers were divided into two groups: Glue Group (GG) where rectal sealing was performed with 2-octyl cyanoacrylate glue and Suture Group (SG) with the rectal defect sealed with simple continuous extracorporeal 3-0 polydioxanone sutures. The rupture pressure of the seals was measured on a rectal burst test. The diathermy polypectomy endoscopic forceps biopsy technique was significantly faster (p<0.001) and provided larger diameter samples. Rectal sealing was significantly faster (p<0.001) in the GG. There was no difference between the two groups with regard to rupture pressure (258.5 mmHg) with air insufflation. Using endoscopic oval biopsy forceps, biopsy samples can only be collected from the surface of the liver, whereas polypectomy forceps with a diathermy loop can be used to collect samples from the tip of the hepatic lobe. There was no difference in rectal rupture pressure in the burst test between the cadavers where sealing was performed with rectal sutures and those where cyanoacrylate adhesive was used.