In vivo Anatomy of the Facial Nerve: Implications for Partial Parotidectomy in Neck Lift Surgery.

Abstract

Partial parotidectomy during neck lift surgery enhances posterior jawline definition by deepening the retromandibular groove. This limited parotidectomy, performed without formal facial nerve trunk identification (Bravo type I), streamlines the overall procedure, saving time in a typically lengthy face and neck lift. There is at present no in vivo data on anatomical parameters relevant to a Type I parotidectomy. The purpose of the authors of this study is to determine the anatomy of the facial nerve in vivo relevant to partial parotidectomy surgery in neck lift procedures. A total of 118 parotidectomy cases were carried out between June 20, 2022 and March 5, 2025. Measurements of the depth of the facial nerve trunk and its inferior division were carried out intraoperatively. Data were recorded prospectively and analyzed statistically. Thirty-six patients (male:female = 20:16), median age 62 years (range, 31-84 years), were included in the study. The facial nerve trunk depth was measured at 23 (standard deviation [SD] 2.0) mm, and the inferior division depth at 15 (SD 2.3) mm from the skin surface. BMI correlated moderately with the depth of the facial nerve trunk (Pearson coefficient 0.6, P < .001), but weakly with the inferior division (Pearson coefficient 0.2, P = .3). There was 1 case of temporary marginal mandibular palsy and 1 case of temporary pan-facial palsy. Both recovered spontaneously at 4 and 6 months, respectively. There was 1 case of sialocele managed with percutaneous aspiration. Type I parotidectomy may be effectively and safely integrated within face and neck lift surgery through a thorough understanding of the relevant facial nerve anatomy.