Searching for the cheese: does ethmoid pneumatization affect the location of the anterior ethmoid artery?

Endoscopic sinus surgery is a widely used technique in otolaryngologic practice. To avoid complications, the locations of important anatomical structures, such as the anterior ethmoid artery (AEA), should be determined preoperatively. We want to evaluate the effect of ethmoid cavity pneumatization on the location of the AEA and to determine consistent landmark(s) for locating the AEA. 524 consecutive patients undergoing sinus CT scans between February and October 2012 were reviewed retrospectively. After the exclusion criteria were applied, 150 CT scans (300 sides) were selected for the study. A statistically significant positive correlation was found between ethmoid pneumatization and the distance of the AEA to the attachment of the inferior turbinate to the lateral nasal wall (Spearman's rho = 0.305; p < 0.001). Likewise, a statistically significant positive correlation was found between ethmoid pneumatization and the distance between the AEA and the frontonasal junction (Spearman's rho = 0.219; p < 0.001). We found that the artery was located mostly between the second and third lamellae [n 211 (71 %) cases]. There was no statistically significant correlation between ethmoid pneumatization and AEA location in terms of the lamellae. Increased ethmoid volume increases the distance of the AEA from the frontonasal junction and the lateral attachment of the inferior turbinate. However, increased pneumatization of the ethmoid cavity did not affect AEA localization in terms of the lamellae. Based on our findings, we suggest that using the lamellae to locate the AEA is reliable.