Age and sex related changes in the configuration of the ethmoid roof and evaluation of asymmetry

Anatomical structure of the ethmoid roof may vary on social and individual differences. The aim of this study was to evaluate left-right asymmetry by determination of ethmoid roof and surrounding structure's diversities depending on age and gender. Our study included paranasal sinus CT scan of 300 patients (147 female, 153 male) who were diagnosed with sinusitis, headache, nasal congestion and runny nose in Afyon Kocatepe University, Faculty of Medicine, ENT, Neurology and Opthalmology departments between 2005 and 2012. Study measurements performed bilaterally on the previously described anterior coronal section where cribriform plate is seen deepest by using a 6-slice MDCT scanner. Keros1; Keros2; and Keros3 was identified in 149 (%24,8), 308 (%51,3) and 143 (%28,3) patients, respectively. There was no significant difference in Keros types with gender and ages. The mean distance between right ethmoid roof and nasal base (female: 52,57±3,89 mm, male: 56,81±4,64 mm) was significantly different according to gender in both sides. There was also a significant difference in mean medial foveal angle of the left side according to gender (female: 118,1±18,34º, male: 111,9±20,00º). The mean right middle concha lenght (female: 23,23±3,84 mm, male: 24,16±3,87 mm) was significantly different according to gender. There was also significant increase in mean maximal orbital height of the both sides according to gender. Male patients have higher maximal orbital height when compared with women. In the analysis without gender differentiation; the distance between ethmoid roof and nasal base (right: 54,73±4,70 mm, left: 55,50±4,90 mm); and middle concha length (right: 23,70±3,80 mm, left: 24,34±3,70 mm) were significantly different on left and right sides. Medial foveal angle and the distance between ethmoid roof and nasal base depends on Keros types. The distance between ethmoid roof and nasal base, shows significant increase; and medial foveal angle shows significant decrease with Keros type. Our study suggests, significant results should be considered when comparing medial foveal angle with gender and Keros types before endoscopic sinus surgery. Keywords: CT, ethmoid roof, cribriform plate, paranasal sinus.