AIM: To provide detailed information about anterior skull base anatomy.

MATERIAL and METHODS: In terms of gender and laterality, the drainage pathways and anatomical variations of the frontal sinus, crista galli and nasal septum in 402 patients were evaluated via computed tomography scans.

RESULTS: The pneumatization patterns of the frontal sinus were as follows: absent, 3.7%; unilateral, 8%; bilateral, 75.1% and triple, 13.2%. The pneumatized crista galli was identified in 120 (29.8%) patients, and its drainage pathway was observed in 54.1% of patients. The sinus septi nasi was identified in 92 (22.8%) and its drainage pathway was observed in 16.3%. The prevalences of the position types of crista galli regarding the cribriform plate were as follows; type I, 18.3%; type II, 64.9%; type III, 16.8%.

CONCLUSION: Despite meticulous knowledge of anatomy, preoperative radiologic evaluation creates the base for successful treatment of anterior skull base pathologies with safer and effective surgery.