Purpose/Aim of the Study:Detailed analysis of retinal structure such as the retinal nerve fiber layer can be performed by spectral-domain optical coherence tomography (OCT). There are no published studies concerning a relationship between retinal nerve fiber layer and human sphenoid sinus volumes. We investigated this relationship.Material and Methods:Spectral-domain OCT. The peripapillary retinal nerve fiber layer (RNFL) thickness and sphenoid sinus volume estimation of both sides of sex-matched patients were retrospectively analyzed.Results:The mean RNFL thicknesses at the left side (91.8 mu m) were significantly smaller than the right side (94.5 mu m) (P=0.040). However, the mean left sinus volume (44.5cm(3)) is larger than the right side, (34.5mm(3)) (P<0.005). Left and right differences of both parameters are statistically significant (P<0.05).Conclusion:There is a negative correlation between mean RNFL thicknesses and mean sinus volumes. To our knowledge, this article is the first report demonstrating the asymmetry relationship between RNFL and sphenoid sinus volumes.