A New Method of Identifying the Posterior Inferior Nasal Nerve: Implications for Posterior Nasal Neurectomy

Introduction: Posterior nasal neurectomy is an effective way of treating recalcitrant rhinitis. The aim of this study is to describe the anatomic relationship between the posterior inferior nasal nerve (PINN) and the structures that might be important for posterior nasal neurectomy. Materials and Methods: An anatomic study was conducted in a university hospital dissection laboratory with 15 formalin-fixed, sagittally cut adult cadaver heads. The distance between PINN and (1) nasal sill, (2) maxillary sinus ostium, (3) posterior fontanel, (4) torus tubarius, and (5) crista ethmoidalis was measured and the location of PINN with respect to the sphenopalatine artery was assessed to define the exact location of PINN. Results: The mean distance between PINN and nasal sill (56.4mm), maxillary sinus ostium (27 mm), posterior fontanel (12.5 mm), torus tubarius (13 mm), and crista ethmoidalis (8 mm) was determined. PINN was found consistently posterior to the sphenopalatine artery where the inferior turbinate attaches to the lateral nasal wall. Conclusion: Instead of finding PINN around the sphenopalatine foramen, PINN can be located more easily posterior to the sphenopalatine artery where the inferior turbinate attaches to the lateral nasal wall without cauterizing the sphenopalatine artery.