Computed tomographic analysis of the prevalence of International Frontal Sinus Anatomy Classification cells and their association with frontal sinusitis.

To determine the radiological prevalence of frontal cells according to the International Frontal Sinus Anatomy Classification in patients undergoing computed tomography of the paranasal sinuses for clinical symptoms of chronic rhinosinusitis, and to examine the association between cell classification and frontal sinusitis development. A total of 180 (left and right) sides of 90 patients were analysed. The prevalence of each International Frontal Sinus Anatomy Classification cell was assessed. Logistic regression analysis was used to compare the distribution of various cells in patients with and without frontal sinusitis. The agger nasi cell was the most commonly occurring cell, seen in 95.5 per cent of patients. The prevalence rates for supra agger cells, supra agger frontal cells, supra bullar frontal cells, supra bullar cells, supra-orbital ethmoid cells and frontal septal cells were 33.3 per cent, 22.2 per cent, 21.1 per cent, 36.1 per cent, 39.4 per cent and 21.1 per cent, respectively. There was no significant difference in the occurrence of any of the cell types in patients with frontal sinusitis compared to those without (p > 0.05). The presence of any of the International Frontal Sinus Anatomy Classification cells was not significantly associated with frontal sinusitis.