ABSTRACT
BACKGROUND: The complexity of the frontal sinus drainage pathway (FSDP) can be challenging even for expert surgeons. Several classifications have been proposed to simplify the understanding of FSDP, whose anatomical variability can be simplified based on the knowledge of its developmental mechanisms. METHODS: Cone-beam computed tomography studies performed at the Unit of Radiology of the University of Brescia between March and November 2012 were retrospectively analyzed. FSDP was classified as medial or lateral to the vertical portion of the uncinate process and the following anatomical variants were studied: agger nasi cell, Kuhn's cells, suprabullar cell, supraorbital ethmoid cell, suprabullar frontal cell, and frontal septal cell. The developmental model of the FSDP proposed by Terracol and Ardouin was analyzed and expected associations between the position of the drainage pathway and anatomical variants were formulated. Statistical associations between anatomical variants and the position of FSDP were calculated and compared with expected associations to validate the developmental model. RESULTS: The anatomical variants of FSDP statistically validated the developmental model of Terracol and Ardouin. CONCLUSION: Knowledge of the possible developmental patterns of FSDP helps the surgeon in the understanding of the complexity of the frontoethmoidal region.