A study of the anterior ethmoidal artery and a new classification of the ethmoid roof (Yenigun classification).

Aims of this study are to analyze the association of the anterior ethmoidal artery's (AEA) visualization with variations in its adjacent structures in coronal, axial, and sagittal CT images, to assess its relation with the ethmoid roof, and, based on this relation, to introduce a new classification for the ethmoid roof. A retrospective, cross-sectional study was performed in a tertiary referral center. In this retrospective, cross-sectional study, the coronal, axial, and sagittal CTs of 184 patients have been surveyed and the AEA canal, the ethmoid roof, and their relations with surrounding structures have been assessed. The Keros classification used to measure the depth of the lateral lamella of the cribriform plate (LLCP) in the ethmoid roof has been modified to include anterior-posterior length of the LLCP. It was shown that the visualization of the AEA canal increases in a statistically significant manner with an increase in the superior-inferior depth and the anterior-posterior length of the LLCP bilaterally. In the presence of supraorbital pneumatization, AEA visualization was shown to increase bilaterally significantly. This study demonstrated a positive correlation between the AEA canal, the LLCP superior-inferior depth, and the anterior-posterior length. It was shown that with the increased depth and length of the LLCP and in the presence of supraorbital pneumatization, the visualization of the artery and hence the injury risks are increased. The LLCP anterior-posterior length is as clinically relevant as is its depth, and a radiologic classification has been defined according to the anterior-posterior length of the LLCP.