title: Deep localized neodymium (Nd)-YAG laser photocoagulation in liver using a new water cooled and echoguided handpiece.
abstract: Thirty-six deep hepatic lesions of localized photocoagulation were induced in 11 pigs by means of a neodymium-YAG laser. Laser applications of 80 W/10 sec (10.190 W/cm2) were transmitted through a handpiece coupled to a water-cooling circulation system to protect the quartz fiber and positioned through an echo-guided trocar. During irradiation, temperature was sufficient for vaporization up to 5 mm from the laser source and high enough for tumor cell kill at a 10-mm distance (54 degrees C/60 sec). Intraoperative ultrasound visualized increasing photocoagulation (12-18 mm), and further controls demonstrated an echo-free core of vaporization progressively covered by increasing fibrosis, well demarcated from normal parenchyma. Microscopy revealed central coagulative necrosis marginated from the third day by a growing fibrosis. By day 20 immunoblasts and mast cells were in profusion in the lesion border, and by day 120 a fibrotic network had invaded the scar and confirmed healing free of complication. This technique is proposed for deep vaporization of disseminated hepatic metastases.
authors.affiliation: Laboratory of Experimental Anatomy, Faculty of Medicine, University Montpellier I, Nîmes, France.
authors.forename: G
authors.initials: G
authors.lastname: Godlewski
authors.forename: S
authors.initials: S
authors.lastname: Rouy
authors.forename: C
authors.initials: C
authors.lastname: Pignodel
authors.forename: H
authors.initials: H
authors.lastname: Ould-Said
authors.forename: J J
authors.initials: JJ
authors.lastname: Eledjam
authors.forename: J M
authors.initials: JM
authors.lastname: Bourgeois
authors.forename: P
authors.initials: P
authors.lastname: Sambuc
mesh_terms: D000818:Animals; D053685:Laser Therapy; D008028:Light Coagulation / Q000295:instrumentation*; D008099:Liver / Q000473:pathology / Q000648:ultrastructure; D008114:Liver Neoplasms, Experimental / Q000601:surgery*; D009354:Neodymium; D013552:Swine; D014463:Ultrasonography
chemical_list: D009354:Neodymium