Variations in the Anatomy of Sphenoid Sinus: A Computed Tomography Investigation

Abstract

Aims: The sphenoid sinus is surrounded by many neurovascular structures which are very vulnerable to intrasphenoid sinus surgeries. The purpose of this study is to investigate the variation of sphenoid sinus structure by CT scan imaging.
 Methodology: This is a retrospective study of 3D images of a paranasal sinus in 129 cases. In this study, three-way metering of the sphenoid sinus, additional septum, pneumatization of the period process (PP), anterior clinoid process (ACP) and greater wing of sphenoid and protrusion and dehiscence of adjacent structures will be assessed.
 Results: Protrusion of internal carotid artery (ICA), a vidian nerve, maxillary nerve (V2) and optical canal were seen respectively 50.4%, 57.36%, 62.5% and 54.3% but dehiscence of this structure was seen 8.5%, 7%, 3.9% and 6.2%. penumtazition of PP, ACP and greater wing of sphenoid were seen 96.87%, 43.9% and 41.1%. Additional septum also is seen in 76% of the population.
 Conclusion: This study demonstrates numerous variations in sphenoid sinus structure. Some of the variations cause many problems during intrasphenoidal surgery. Therefore, physicians should evaluate patients completely before surgery.

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

“…The occurrence of an aerated greater wing of sphenoid (17.9%) was lower than the findings from a previous Nigerian study (Osun state) by Famurewa et al as well as reports from Sudan and Iran ( 2 , 12 , 20 ). However, the frequency was higher in the West Africans of Benin ( 6 ) ( Table 4 ).…”

“…The prevalence of the pneumatized anterior clinoid process (22.6%) was higher than the reports in previous Nigerian studies by Fasunla et al, Onwuchekwa and Alazigha, Famurewa et al, and other studies outside Nigeria ( 5 , 6 , 7 , 12 , 18 ) ( Table 4 ). However, Joghataei et al and Gungor and Okur documented higher frequencies in Iran and Turkey respectively ( 2 , 19 ) ( Table 4 ). The population differences could be ascribed to genetics, ethnicity, race, and environmental factors.…”

“…The body is aerated forming the sphenoid sinus of varying sizes and shapes among individuals. This sinus is the most inaccessible and most variant paranasal sinus whose pathologies are difficult to diagnose due to its deep location ( 2 , 3 ). The sinus exists at birth as a small mucosal sac of red marrow that evaginated posteriorly from the nasal capsule at the sphenoethmoidal recess during the 3 rd to 4 th month of intrauterine life ( 4 ).…”

Anatomical variation in the sphenoidal sinuses in patients with chronic rhinosinusitis: A CT scan study

“…Pneumatization of the ACP exposes the ON in the sinus cavity. 24 Extensive pneumatization brings neurovascular structures, such as the ON, cavernous sinus, ICA and ACP, into proximity of the sinuses. 25 , 26 , 27 …”

Clinically Significant Variation of Paranasal Sinuses on CT-Scan

“…CT imaging technique is one of the most accurate methods for imaging of the paranasal sinuses to visualize various structures along with their extent and depth. This method allows doctors to distinguish the variations in the anatomical relations of the PNS, due to the obvious clear-cut illustration of the bony structures 33,3,4,21,6 .…”