title: Facial nerve identification with fluorescent dye in rats.
abstract: PURPOSE The parotidectomy technique still has an elevated paresis and paralysis index, lowering patient life's quality. The correct identification of the facial nerve can prevent nerve damage. Fluorescent dye identifies nerves in experimental studies but only few articles focused its use on facial nerve study in parotidectomies. We aimed to stain the rat facial nerve with fluorescent dye to facilitate visualization and dissection in order to prevent injuries. METHODS Forty adult male Wistar rats were submitted to facial injection of saline solution (Gsf-control group, 10) or fluorescent dye solution (Gdye group, 30) followed by parotidectomy preserving the facial nerve, measuring the time for localization and facility of localization (LocTime and LFN). Nerve function was assessed using the Vibrissae Movements (PMV) and Eyelid Closure Motion (PFP) scores. RESULTS Nerve localization was faster in Gdye group, with 83% Easy LFN rate. The Gdye group presented with low nerve injury degree and better PMV and PFP scores, with high sensitivity and accuracy. CONCLUSIONS This experimental method of facial nerve fluorescence was effective for intraoperative nerve visualization, identification and preservation. The technique may be used in future facial nerve studies, translated to humans, contributing to the optimization of parotid surgery in the near future.
authors.affiliation: Neck Surgery Department, Universidade Federal de São Paulo, Brazil.
authors.forename: Giulianno Molina
authors.initials: GM
authors.lastname: de Melo
authors.affiliation: Neck Surgery Department, UNIFESP, Sao Paulo, SP, Brazil.
authors.forename: Onivaldo
authors.initials: O
authors.lastname: Cervantes
authors.affiliation: Department of Physiology, Neurophysiology Laboratory, UNIFESP, Sao Paulo, SP, Brazil.
authors.forename: Luciene
authors.initials: L
authors.lastname: Covolan
authors.affiliation: UNIFESP, Sao Paulo, SP, Brazil.
authors.forename: Heloisa Allegro
authors.initials: HA
authors.lastname: Baptista
authors.affiliation: Department of Physiology, Neurophysiology Laboratory, UNIFESP, Sao Paulo, SP, Brazil.
authors.forename: Elenn Soares
authors.initials: ES
authors.lastname: Ferreira
authors.affiliation: Otorhinolaryngology Head and Neck Surgery Department, UNIFESP, Sao Paulo, SP, Brazil.
authors.forename: Marcio
authors.initials: M
authors.lastname: Abrahao
mesh_terms: D000818:Animals; D002232:Carbocyanines / Q000008:administration & dosage*; D004210:Dissection / Q000379:methods; D005154:Facial Nerve / Q000601:surgery*; D005456:Fluorescent Dyes / Q000008:administration & dosage*; D008297:Male; D008845:Microinjections / Q000295:instrumentation; D008859:Microscopy, Polarization; D023421:Models, Animal; D015588:Observer Variation; D010306:Parotid Gland / Q000601:surgery*; D017208:Rats, Wistar; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: C000611943:3,3'-dilinoleyloxacarbocyanine; D002232:Carbocyanines; D005456:Fluorescent Dyes