Sphenopalatine Foramen Computed Tomography Landmarks.

Objective: The aim of the study was to assess different radiologic bony landmarks for endoscopic localization of the sphenopalatine foramen (SPF).

Methods: Paranasal computed tomography (CT) scans of adults without sinonasal pathology were included. On axial cuts, the anteroposterior distances from the SPF to maxillary line, anterior head of the middle turbinate, basal lamella of the middle turbinate, choanal arch, and posterior fontanel of the maxillary sinus ostium were measured. While on coronal cuts, the vertical distances from the SPF to the nasal floor was measured. The registered measurements were then studied and statistically analyzed.

Results: In 70 patients (140 sides, 840 measurements), the mean distances from the SPF to nasal floor, choanal arch, maxillary line, anterior head of the middle turbinate, basal lamella, and posterior fontanel were 25.6 ± 2.4, 8.5 ± 1.38, 36.4 ± 2.6, 34.6 ± 4.26, 8.1 ± 1.27, and 13.7 ± 1.7 mm, respectively, without significant differences between right and left sides. Females showed significantly shorter mean distances between SPF and the nasal floor (P = 0.0011), choanal arch (P = 0.0459), and posterior fontanel (P < 0.0001) than males. While no significant differences were detected between both sexes as regard distances from SPF to maxillary line (P = 0.5579), anterior head of middle turbinate (P = 0.8581), and basal lamella (P = 0.0638).

Conclusion: Preoperative CT can provide multiple easily detected, reliable, and simple bony landmarks that can help SPF endoscopic localization. Thus the authors recommend adding these measurements to the preoperative CT checklist for patients scheduled for sphenopalatine artery ligation and/or excision of vascular lesions.