Morphometric Analysis of Sphenoid Sinus and Its Surgical Importance in Endoscopic Sinus Surgeries: A CT-based Study
Keywords:
Sphenoid sinus, Computed tomography, Morphometry, Pneumatization patterns, Endoscopic sinus surgeryAbstract
Background: The sphenoid sinus exhibits considerable anatomical variability and lies adjacent to critical neurovascular structures, posing challenges during endoscopic sinus and transsphenoidal skull-base procedures. Region-specific morphometric data are essential to optimize surgical planning and minimize complications.
Methods: In this cross-sectional study, high-resolution CT scans of 200 adult patients (110 males, 90 females) from Northern India were analyzed. Anteroposterior length, transverse width, vertical height, and estimated volume of each sphenoid sinus were measured. Pneumatization patterns were classified as conchal, presellar, sellar, or postsellar. Septal anatomy (number, completeness, deviation, attachments) and bony protrusion/dehiscence of the internal carotid artery, optic nerve, and Vidian nerve were recorded. Bilateral and sex-based differences in dimensions and volume were assessed by independent-samples t-tests; volume differences across pneumatization types by one-way ANOVA with Tukey’s post-hoc tests; and categorical variables by Chi-square tests. Statistical significance was set at p < 0.05.
Results: Mean dimensions were 30.6 ± 4.2 mm (anteroposterior), 21.4 ± 3.5 mm (transverse), and 24.8 ± 3.7 mm (vertical), with no significant side-to-side differences (p ≥ 0.08). Mean sinus volume was significantly larger in males (9,200 ± 2,200 mm³) than in females (7,800 ± 1,800 mm³; t = 5.42, p < 0.001). Pneumatization distribution was sellar in 65%, presellar in 20%, postsellar in 10%, and conchal in 5%. Conchal (5,200 ± 1,000 mm³) and presellar (7,000 ± 1,500 mm³) volumes were significantly smaller than sellar (8,800 ± 2,000 mm³; p < 0.001 and p = 0.02, respectively), while sellar versus postsellar volumes did not differ (p = 0.45). Single septa occurred in 40%, two or more septa in 35%, and no septa in 25%; 12% of septa attached to the internal carotid artery and 8% to the optic nerve. Protrusion rates were 10% for the carotid artery, 7.5% for the optic nerve, and 4% for the Vidian nerve.
Conclusions: The sphenoid sinus demonstrates bilateral symmetry in linear dimensions but significant sex-related volumetric differences. Sellar pneumatization predominates, and septal and bony variations that tether or expose neurovascular structures are common enough to warrant meticulous preoperative CT evaluation. These findings should guide individualized surgical planning and inform the use of image-guided navigation to enhance intraoperative safety
Downloads
Metrics
References
Rehman DES, Mohd Ismail ZI, Jawdat D, Ali SA, Sapiai NA, AlAli A. Relationship of anatomical variations of sphenoid sinus and the outcomes of endoscopic endonasal transsphenoidal surgeries: a systematic review. Eur Arch Otorhinolaryngol. 2024;1–14.
Oliveira JMM, Alonso MBCC, de Sousa e Tucunduva MJAP, et al. Volumetric study of sphenoid sinuses: anatomical analysis in helical computed tomography. Surg Radiol Anat. 2017;39:367–374.
Gibelli D, Cellina M, Gibelli S, et al. Volumetric assessment of sphenoid sinuses through segmentation on CT scan. Surg Radiol Anat. 2018;40:193–198.
Nejaim Y, Gomes AF, Valadares CV, et al. Evaluation of volume of the sphenoid sinus according to sex, facial type, skeletal class, and presence of a septum: a cone-beam computed tomographic study. Br J Oral Maxillofac Surg. 2019;57(4):336–340.
Tuang GJ, Zahedi FD, Husain S, et al. Volumetric evaluation of the sphenoid sinus among different races in the Southeast Asian (SEA) population: a CT study. Int J Med Sci. 2023;20(2):211.
Göçmez C, Göya C, Hamidi C, et al. Evaluation of the surgical anatomy of sphenoid ostium with 3D computed tomography. Surg Radiol Anat. 2014;36:783–788.
Pirinc B, Fazliogullari Z, Guler I, et al. Classification and volumetric study of the sphenoid sinus on MDCT images. Eur Arch Otorhinolaryngol. 2019;276:2887–2894.
Kapur E, Kapidzic A, Kulenovic A, et al. Septation of the sphenoid sinus and its clinical significance. Int J Collab Res Intern Med Public Health. 2012;4(10):1793.
Jaworek-Troć J, Zarzecki M, Zamojska I, et al. The dimensions of the sphenoid sinuses: evaluation before the functional endoscopic sinus surgery. Folia Morphol. 2021;80(2):275–282.
Singh P, Hung K, Ajmera DH, Yeung AWK, von Arx T, Bornstein MM. Morphometric characteristics of the sphenoid sinus and potential influencing factors: a retrospective CBCT assessment. Anat Sci Int. 2021;96(4):544–555.
Ganesh VL, Dharanipathy S, Pavana V, et al. A CT‐based morphometric study of skull base parameters relevant to endoscopic endonasal surgery. Surg Neurol Int. 2024;15:68.
Ominde BS, Ikubor JE, Iju WJ, Igbigbi PS. Dimensions of the sphenoid and ethmoid sinuses on CT: clinical implications and role in sex determination. Mustansiriya Med J. 2023;22(1):71–79.
Orhan I, Ormeci T, Bilal N, Sagiroglu S, Doganer A. Morphometric analysis of sphenoid sinus in patients with nasal septum deviation. J Craniofac Surg. 2019;30(5):1605–1608.
Gurlek Celik N, Akman B. Analysis of sphenoid sinus and ethmoid sinus volume and asymmetry by sex: a 3D-CT study. Surg Radiol Anat. 2024;46(5):551–558.
Downloads
Published
How to Cite
Issue
Section
License
This work is licensed under a Creative Commons Attribution 4.0 International License.
You are free to:
- Share — copy and redistribute the material in any medium or format
- Adapt — remix, transform, and build upon the material for any purpose, even commercially.
Terms:
- Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
- No additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.
