Influence of the water jet system vs cavitron ultrasonic surgical aspirator for liver resection on the remnant liver

Laparoscopic Liver Resection Utilizing a Water Jet Scalpel for Patients With Liver Fibrosis

Introduction A variety of devices are utilized in order to resect liver parenchyma in laparoscopic liver resection. However, liver fibrosis makes hepatectomy problematic because the liver is rigid and prone to bleeding. The water jet scalpel, which dissociates the liver parenchyma with a jet stream has no thermal damage and is clinically utilized in liver resection, but its safety and efficacy during laparoscopic liver resection for patients with liver fibrosis remain unknown. Methods We analyzed patients who underwent laparoscopic liver resection utilizing the water jet scalpel with liver fibrosis at our hospital. A water jet scalpel was used for liver parenchymal transection, and a saline-linked ball-tipped electrocautery was simultaneously used for hemostasis. Results Subsectionectomy was one case, left lateral sectionectomy was two cases, and non-anatomical liver resection was three cases. The median blood loss was 70 mL (24-104 mL). There was no need for the intraoperative Pringle's maneuver. No perioperative blood transfusion was performed, and there were no postoperative complications, including posthepatectomy liver failure. Conclusion It was suggested that laparoscopic liver resection in patients with liver fibrosis can be safely performed with the water jet scalpel.

Micro-mechanism study on tissue removal behavior under medical waterjet impact using coupled SPH-FEM

To fully grasp the numerical characteristics of the interaction process between medical waterjet and soft tissue, the smoothed particle hydrodynamics (SPH)-finite element method (FEM) was used in the simulation of this complex process to avoid the unstable error caused by indirect measurement in experiments. The SPH was applied to the numerical simulation of medical waterjet, and a three-dimensional model of gelatin sample was proposed with the FEM. The impact process between two extremely deformed materials was reproduced, and the established model was verified by comparison with experimental data; the comparison showed relatively consistent results. The separation effect under three operating modes was deduced with the stress and strain range. For the vertical impact condition, the higher the waterjet impact pressure is, the higher the biological tissue deformation bulge height is. For oblique intrusion, the longitudinal separation rate decreases and the kerf width increases with the increase of the incident angle. For the moving impact condition, with the increase of the waterjet moving speed, the longitudinal high-stress distribution range of the impact object decreases slightly.