Relationship of anatomical variations of sphenoid sinus and the outcomes of endoscopic endonasal transsphenoidal surgeries: a systematic review.

Background: The sphenoid sinus features many anatomical variations between individuals from different populations in the world. The understanding of these variations is important for the surgeons to plan for surgeries which involve intervention through the nasal approach. The aim of the present systematic review was to perform a qualitative synthesis of available studies which assess the effect of sphenoid sinus (SS) anatomical variations on the outcomes of endoscopic endonasal transsphenoidal surgeries (ETSS).

Methods: The current review followed PRISMA 2020 guidelines. A systematic advanced electronic search was performed in four databases Medline (via PubMed), Scopus, Web of Science (WoS) and Lilacs in December 2023. Studies that assessed the anatomical variations of the SS that affect the outcomes of ETSS were eligible for inclusion. A qualitative synthesis of the methodology and results of the included studies was carried out. Quality assessment was performed using the National Institute of Health (NIH) quality assessment tool (last accessed on December 24, 2023).

Results: A total of 14 studies were included in the qualitative synthesis. Most of the studies included in the review found that the sellar pneumatization was the commonest followed by the postsellar type. Single intersphenoid sinus septum (ISS) was found to be the most common variation, which is more frequently found in males compared to females. There was sex difference seen in the attachment of the ISS to the carotid canal. It is more commonly attached to the posterolateral wall of the sinus in males compared to the females. Though complicated cases were less compared to uncomplicated ones, cerebrospinal fluid (CSF) leak was the leading post operative complication amongst the complicated cases and paranasal sinus (PNS) computed tomography (CT) scan showed ISS findings differed from intraoperative findings.

Conclusion: It is concluded that the ISS poses the commonest anatomical variations encountered during the ETSS. During planning for transsphenoidal endoscopic procedure, the ISS should thoroughly be assessed to minimize potential surgical complications.