Evaluation of the Best Power Setting of Laser Waves in Pancreatic Surgery: ECHO ND-YAG Laser Ablation on Bovine Pancreatic Tissue

Abstract

Background:Pancreatic surgery is one of the most difficult and life-threatening surgical thera-py especially during necrotizing pancreatitis and advanced solid neoplasms.Aim of the study: To evaluate the possibility to use ECHO Neodymium-Doped Yttrium Alu-minium Garnet (ND-YAG) laser in pancreatic surgery and to establish the best power setting for the application on pancreatic tissue.Methods: An ECHO Laser ND-YAG 1064 nm, at the constant fluence of 1800 J/cm2 was used. The laser waves were inserted inside of the samples with optical fibers of 500 micron diam-eter for a pre-established timing (11 min, 6 min, 4 min) in order to reach the constant fluence. Samples were, then, prepared for hystological examination.Results: At 3W power setting, the pancreatic tissue was not macroscopically modified except for an increased cutting consistency. Histological examination showed no substantial micro-scopical differences in pancreatic cells that appeared only partially burnt (in fact, nuclei and membranes are still recognizable). The vessels in the surrounding area have the normal mor-phological aspects. At 5W, macroscopically the presence of a completely burnt area, corresponding to the site of direct interaction of laser and tissue, was found and the surrounding tissue did not appear sub-stantially modified.Histological examination showed the complete absence of cells in the burnt area and an impor-tant heat damage of the surrounding cells till the 2th centimeter from the site of laser application. The vessels in the heat damage area appeared completely coagulated. At the power of 7 W, the burnt area was about twice than in the previous setting and histological examination showed the complete absence of cells in the burnt area and a larger heat damage of the nearest cells (till the 4th centimeter from the application site). The vessels in heat damage area were found completely coagulated.Conclusions:A power setting between 4 and 6 W have been found as the best one for laser ap-plication on pancreatic tissue because a complete destruction of the cells in the site of applica-tion but a limited heat damage in the surrounding healthy cells have been obtained.