1. The development of the ethmoidal cells begins during fetal life.

2. 25 During execution of this maneuver , the anterior ethmoidal artery and must be cauterized with forceps.

3. Conclusion: The imaging anatomy of ethmoidal roof, cribrum and understanding of the formation of olfactory fovea is the instructive significance for anterior skull base surgery.

4. Figure T2-weighted axial image once again demonstrates a large, heterogeneous lesion located in the ethmoidal sinus (arrow). The lesion is predominately isointense to grey matter.