Endonasal anatomy of the olfactory neural network: Surgical implications

Abstract

Objectives/hypothesis: Define the anatomic distribution of the olfactory filaments within specific mucosal regions of the nasal cavity.

Study design: Cadaveric study.

Methods: Seventeen cadaveric specimens (34 sides) were dissected to study the anatomical distribution and density of olfactory fila within different regions of the nasal cavity. Olfactory fila were dissected retrogradely to their point of entry into the anterior cranial fossa through the cribriform plate. Anatomic relationships among various components of the olfactory system and their corresponding arterial supply were determined subjectively.

Results: The highest density of olfactory fila was found at the mucosa of the ethmoid roof and superior turbinates. Olfactory fila were found at regions not previously considered to be part of the olfactory system: lateral wall of the nose, ethmoidal bullae, and between the os sphenoidale and arc of the posterior choana. Furthermore, at the septum, 20% of the olfactory fila crossed contralaterally before exiting the nose. The anterior ethmoidal arteries were the primary blood supply to the olfactory epithelium.

Conclusions: This study suggests that olfactory filaments extend beyond previously established boundaries. These findings may have clinical implications regarding oncologic resections and could serve as the foundation for the development of techniques that better preserve olfactory function.

Level of evidence: NA Laryngoscope, 2473-2477, 2018.

Keywords: Olfaction; anatomy; endonasal surgery; olfactory epithelium; olfactory fila.