A Multislice Computed Tomographic Study of the Sphenoid Sinus

Sphenoid sinus is located in the body of sphenoid bone, closed with a thin plate of bone tissue that separates it from the surrounding important structures such as the optic nerve, optic chiasm, cavernous sinus, pituitary gland, and internal carotid artery. Detailed, meticulous preoperative radiological study of sphenoid sinus variations as in Onodi cells (Sphenoethmoidal air cell) is an anatomical variant of the paranasal sinuses, important due to its close proximity to the optic nerve and internal carotid artery. , Pnumatization pattern as the extent of pneumatization is highly variable and potentially jeopardizing to surrounding vital structures , Septation pattern , Intercarotid distance (in millimeters), Bony covering of carotid artery, Bony covering of optic nerve.is the key to successful and safe functional endoscopic sinus surgery and transsphenoidal surgery. The purpose of the study is to delineate the sphenoid sinus radiologically using the multislice computed tomography and to decrease morbidity and mortality during skull base surgeries as the sphenoid sinus is one of the most variable of all sinuses and its relation to vital vascular and nervous elements make its approach a challenge for endoscopic surgeons