OBJECTIVETo understand the anatomy of the supraorbital ethmoid cell and its relationship with the frontal sinus drainage pathway.

METHODSFive patients (5 sides) who had supraorbital ethmoid cell underwent endoscopic frontal sinus surgery. Computed tomographic (CT) scans of the sinuses were obtained in coronal and axial views. The frontal sinus ostium and the supraorbital ethmoid cell were endoscopically identified respectively.

RESULTSOn coronal CT scans, the supraorbital ethmoid cell was a separate cell lateral to the frontal sinus. And on axial CT scans, it was lateral and posterior to the frontal sinus drainage pathway. Under endoscope, its opening was lateral and posterior to the frontal sinus ostium.

CONCLUSIONSThe supraorbital ethmoid cell extended superolateral the boundaries of the lamina papyracea and the roof of the ethmoid to pneumatize the orbital plate of the frontal bone.