Introduction: In the humans, paranasal air sinuses play various roles like- make the skull light weight, add the resonance to the voice etc. We have frontal, ethmoid, maxillary and sphenoid sinuses. Out of these, sphenoid sinuses (SS) have got the importance because of trans-sphenoid approach for the pituitary surgeries and skull base surgeries. Therefore, the knowledge of anatomical variation of SS has a significant role in surgical access of pituitary fossa and also, can anticipate the difficulties in surgery.

 

Aim: This is the study to find out the variations of SS and their relations to adjacent neurovascular structures with surgical point of view.

 

Materials and Methods: Computed Tomography (CT) scans of 150 living subjects (53 females and 97 males) were taken in coronal, sagittal and axial planes. Contiguous slice CT technique was used with 1 mm section thickness. The p-value was calculated to find out the association between extent of pneumatization of sphenoid sinus and protrusion or dehiscence of maxillary nerve (MN), vidian nerve (VN), optic nerve (ON) or internal carotid artery (ICA) in the sinus. Chi square test was used for the calculation of p-value.

 

Results: It was observed that there were 2 cases with conchal pneumatization, 29 cases with pre-sellar pneumatization, 47 cases with sellar pneumatization, 72 cases with post-sellar pneumatization. It was observed that pneumatization of greater wing of sphenoid sinus (GWS) in 40 cases, pterygoid process (PP) in 39 cases and anterior clinoid process (ACP) in 34 cases. Onodi cell were noticed in 17 sinuses. Protrusion of ICA was found in 27 sinuses. The p-value was highly significant for the association between pneumatization of sphenoid sinus and protrusion or dehiscence of nerves or ICA in the sinus. Chi square test was used for the calculation of p-value. Posterior attachment of Inter Sinus Septa (ISS) was noticed in the midline in 36 individuals (24%) and deviated from midline in 113 individuals (75%). Accessory septae were noticed in 76 sinuses (51%).

 

Conclusion: Due to widespread pneumatization of SS, it lies in close relation with MN, ON, VN & ICA. Newer techniques were helpful for the safety of the patient during intra-operative and post-operative period.

 

Keywords: Internal carotid artery, Maxillary nerve, Optic nerve, Pneumatization, Vidian nerve