The Nd:YAG LIMAX® 120 high-output laser: local effects and resection capacity on liver parenchyma

Abstract

Various technical options are available for the resection of liver metastases, including CUSA, Ultracision, water-jet, and stapler devices. It has been shown that new generation high-output lasers are suitable for the resection of lung metastases. The goal of the present study was to evaluate the local effects of laser application on liver parenchyma. Livers of freshly slaughtered pigs (N = 6) were analyzed. The handheld laser was vertically held in the clamp of a hydraulic machine and sharply focused on the liver surface. The diode pumped Nd:YAG laser LIMAX® 120 (Gebrüder Martin GmbH & Co. KG, Tuttlingen, Germany) moved evenly over the liver surface at speeds of 5, 10, and 20 mm/s. Laser outputs of 60 and 120 W were applied at every speed. Histological sections (hematoxylin and eosin (HE) staining) of the extension area of vaporization and coagulation were analyzed by the use of the ImageJ software. In addition, the area of the liver parenchyma cut by the laser within 1 min was measured. The vaporized zone appeared wedge-shaped after histological section, whereas the area of coagulation appeared radiated outward. At 10 mm/s and 60 W, the mean vaporization of the measured zone was 356.6 ± 3.9 μm in length. Superficial coagulation was observed at 20 mm/s laser speed, without effective resection. At 120 W and 5 mm/s working speed, the mean vaporization zone and the average width of coagulation were largest with 664.6 ± 5.9 and 375.6 ± 2.3 μm, respectively. The laser output power of 120 W allowed resection of an area of 6 ± 0.4 cm(2) of liver parenchyma within 1 min. The Nd:YAG Laser LIMAX® 120 might be an effective tool for liver parenchyma dissection when it is applied at maximum output (120 W) and at a constant working speed of 5 mm/s.