Sphenoid sinus pneumatization, septation, and the internal carotid artery: A computed tomography study

Abstract

Background: The air spaces of the nasal cavity and the sphenoid sinus (SS) constitute a convenient corridor to access lesions of the skull base using the endoscopic endonasal transsphenoidal approach (EETA). Safe EETA depends on the SS and skull base anatomy of the patient. Individual variations exist in the degree and pattern of SS pneumatization. This study aims to examine the variations in SS pneumatization, the inter-sphenoid septum (ISS), and their relationship with the internal carotid artery (ICA) among adult Nigerians. Materials and Methods: We reviewed computerized tomography (CT) images of 320 adult patients that had imaging for various indications. This excluded those with traumatic, inflammatory, or neoplastic process that may alter anatomical landmarks. The images were evaluated for the types of SS pneumatization, number and insertion of ISS, and the protrusion of ICA into the sinus cavity. Results: Prevalence of SS pneumatization types: 1.9% conchal, 1.2% presellar, 56.6% sellar, and 40.2% postsellar. The lateral extension of SS occurred into the pterygoid in 138 patients (45.1%), greater wing 112 (35%), lesser wing 37 (11.6%), the full lateral type was seen in 97 (30.3%) patients. One ISS occurred in 150 (46.9%) patients, 162 (50.6%) had multiple, and 8 (2.5%) had none. ISS insertion into ICA bony covering occurred in 101 (31.6%) patients, whereas protrusion of ICA into SS cavity occurred in 110 (34.4%) patients. Conclusion: Variations of the SS, ISS, and ICA anatomy are present among native Africans. Detailed imaging evaluation of each patient is considered for EETA is mandatory.

Morphometric characteristics of the sphenoid sinus and potential influencing factors: a retrospective assessment using cone beam computed tomography (CBCT)

“…The location of the inter-sinus septum in the present study was consistent with the findings of Rennie et al and Anusha et al (Anusha et al 2014;Rennie et al 2017). The inter-sinus septum is considered to be a crucial structure for trans-sphenoidal surgery as it lies in close proximity to the optic nerve and internal carotid artery and sometimes may be attached to the bone covering these vital structures (optic nerve and internal carotid artery) (Famurewa et al 2018). Therefore, careful consideration is (Sareen et al 2005) which was in contrast to the present findings, where a frequency of 7.4% for solitary and 1.4% for compound sinuses was observed.…”

Pneumatization Patterns of the Sphenoid Sinus in Adult Nigerians and Their Clinical Implications

“…The predominant pneumatization pattern was the sellar type (53.9%) whose frequency was comparable to 56.6% documented in Osun state, Nigeria ( 12 ). Our findings were higher than those reported in Turkey and Iraq and lower than the prevalence in India ( 4 , 13 , 14 ).…”

“…Our findings were higher than those reported in Turkey and Iraq and lower than the prevalence in India ( 4 , 13 , 14 ). The frequency of the presellar type, 19.3% was higher than 1.2% reported in a previous Nigerian study by Famurewa et al ( 12 ) According to literature reports, the frequency of the presella type was higher in Ethiopians (25.5%) and lower in Turkish (3.9%), and Indians (9%) ( 3 , 14 , 15 ). The conchal type had a low prevalence (8.3%) although this was higher than some previously documented reports ( 3 , 12 , 15 ).…”

Variations of Surgicalanatomy in and Around Sphenoid Sinus: A Computed Tomographic Study

“…In the greater wing of sphenoid: Pneumatization of greater wing of sphenoid was considered when it extends beyond a vertical line crossing foramen rotundrum. In our study 4%(n=4) patients showed pneumatization of greater wing of sphenoid In previous studies it was found between 1.8% -20% (27,38,39).…”