The Anatomical Relationship between the Anterior Ethmoid Artery, Frontal Sinus, and Intervening Air Cells; Can the Artery Be Useful Landmark?

Background and ObjectivesZZThe anatomy surrounding the frontal sinus (FS) and the anterior ethmoid artery (AEA) is variable and complex.We tried to determine the value of AEA as a landmark for finding FS during endoscopic sinus surgery.Subjects and MethodZZUsing the high-resolution CT scans of coronal and sagittal reconstruction, the distance between AEA and FS (D-AF) and the number and type of intervening cells between these two structures were investigated.Next, the distance between AEA and the anterior skull base (D-AS) was measured and the correlation between D-AF and D-AS was analyzed.ResultsZZA total of 119 nasal cavities from 70 subjects was analyzed.Of these analyzed, AEA was located just behind the frontal recess in only 17 nasal cavities (14%) and one or two intervening cells were located between FS and AEA in the remaining 86% of the nasal cavities.The most frequent type of intervening cells was supra bullar cell, followed by supraorbital and frontal bullar cells.The mean D-AF and D-AS measurements were 8.58±5.56mm (0-22.6 mm) and 1.65±1.90mm (0-6.7 mm), respectively.D-AS was not significantly correlated with the distance between the FS and AEA (p=0.433),therefore, D-AS could not be predicted.ConclusionZZThe relationship between FS and AEA was non-predictable, and in most cases, there were one or two intervening cells between FS and AEA.Therefore a thorough review of thin section CT scans is necessary.