Applicability of the Diode Laser in the Larynx and trachea of Pigs

• Grant number: 15/17847-1
• Support Opportunities: Regular Research Grants
• Start date: June 01, 2016
• End date: May 31, 2018
• Field of knowledge: Health Sciences - Medicine - Surgery
• Principal Investigator: Paulo Francisco Guerreiro Cardoso
• Grantee: Paulo Francisco Guerreiro Cardoso
• Host Institution: Instituto do Coração Professor Euryclides de Jesus Zerbini (INCOR). Hospital das Clínicas da Faculdade de Medicina da USP (HCFMUSP). Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated researchers: Helio Minamoto ; José Pinhata Otoch ; Marília Wellichan Mancini ; Mauro Canzian ; Paulo Manuel Pêgo-Fernandes

Abstract

Airway stenosis is a complex problem that usually requires surgery, multiple dilatation sessions and prostheses to maintain airway continuity. The laryngeal fissure is a major surgical procedure designed for patients with laryngo-tracheal stenosis. In addition to being a major surgical undertaking, it requires several subsequent procedures such as laryngeal and tracheal stenting for as long as 2 years. Despite its favorable results, it often causes sequelae such as voice dysfunction and disordered deglutition in adults and children submitted to the procedure that impacts on the quality of life. In order to minimize the surgical trauma we hypothesized that the use of a contact diode laser will minimize the local trauma and, by the same token, allow the procedure to be performed endoscopically. However, little is known about the depth and extension lateral thermal zone caused by the laser in the larynx and proximal trachea. This study is focused on the assessment of the efficacy and lateral damage caused by the contact diode laser using different potency levels in a normal larynx. Thirty swine weighing 25-30 kg will be anesthetized, submitted to a tracheostomy. A median anterior laringofissure will be produced and the animals randomized into 3 groups: Control (n=4)-section of the inner larynx and proximal trachea with a conventional scalpel; Eletrocautery (n=16)- section of the inner larynx and proximal trachea with electrocautery (Valleylab Force 2, model 70202F, Boulder-CO, USA; potency=10, 20, 30, 40;cut mode; n=4 each subgroup); Diode laser (MediLaser 980nm, DMC São Carlos-SP) (n=16)- section of the inner larynx and proximal trachea using 4 different potencies (10W, 15W, 20W, 25W, n=4each subgroup). Upon completion of the incisions, the larynx and proximal trachea are excised and prepared for histology (hematoxylin-eosin) and laryngo-tracheal sections evaluated using light microscopy at 50x e 100x power. The parameters assessed by morphometric analysis are lateral extensionof the thermal zone and depth of the section. Data obtained will be represented numerically (area in µm2) and stored in an electronic worksheet (MS Excel). Variables in each group will be compared by ANOVA and the level of significance is set for p values less than 0,05.Keywords: trachea; larynx; laser; pigs; surgery (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MENEZES, ARTEIRO QUEIROZ; GUERREIRO CARDOSO, PAULO FRANCISCO; NAGAO, CHRISTOPHER KENGO; MINAMOTO, HELIO; BIBAS, BENOIT JACQUES; SOARES RODRIGUES, ISAAC DE FARIA; OTOCH, JOSE PINHATA; DOLHNIKOFF, MARISA; CANZIAN, MAURO; MANCINI, MARILIA WELLICHAN; et al. Posterior laryngofissure using a surgical contact diode laser: an experimental feasibility study. Lasers in Medical Science, v. 34, n. 7, p. 1441-1448, SEP 2019. (15/17847-1, 16/25437-0)