DOI: http://dx.doi.org/10.18203/2320-6012.ijrms20191525

Anatomical variations of intra-sphenoid sinus septations in a sample of Kashmiri population: a non-contrast computed tomography study

Abdul Haseeb Wani, Yassar Shiekh, Arshed Hussain Parry, Zahid Qayoom

Abstract


Background: The sphenoid sinus shows multitude of variations in pneumatization, size and pattern of septations leading to differences in its segmentation. Pre-operative knowledge of their attachment especially to posterolateral bony walls covering vital structures is of utmost importance for a safe trans-sphenoidal approach for various surgical procedures involving skull base. Non-contrast computed tomography (NCCT) with its ability to provide multiplanar reformations (MPR) with sharp algorithms is now a reference standard for visualization of these intra-sphenoid sinus septations preoperatively. The objective of this study was to determine the number and attachment of intra-sphenoid sinus septations in a Kashmiri population sample.

Methods: NCCT head images of 591 patients in the age range of 16 to 75 years were analyzed retrospectively. Individuals with age less than 16 years, previous surgery involving skull base/sphenoid sinus, trauma causing hem sinus/fractures around skull base or having space occupying lesions around skull base/sphenoid sinus were excluded from the study. On the CT workstation multi-planar coronal, sagittal and axial reconstructions were performed and subsequently examined.

Results: The age range was 16 to 75 years with mean age of 43.56 years of which 453 (76.6%) were males and 138 (23.4%) were females. Single intra-sphenoid septation was the most common anatomic variant in present study (79.7%) being complete in 71.7% and partial or incomplete in 8% of the examined subjects. Double septa were found in 11% inpresent study and more than 2 septae in 3.4%. After sellar attachment (51%) the next most common site of attachment was to the carotid canal (29.5%) (23% to left ICA and 6.5% to the right ICA).

Conclusions: Intricate knowledge about sphenoid sinus, its pneumatization and anatomical variations in intra-sphenoid sinus septations and its relationship with the surrounding vital structures is of utmost importance before performing any endoscopic/open surgery involving skull base via trans-sphenoidal approach. The present study shows that a significant percentage of septal attachment to the carotid canal makes main sphenoidal septum as not so reliable landmark for endoscopic procedures as used to be in the pre-imaging era. Thus, preoperative CT is mandatory to avoid injuries to para-sellar neurovascular and glandular structures.


Keywords


Computed tomography, Intra sphenoid sinus, Intra-sphenoid sinus septation, Multi-planar reformation, Para-sellar, Trans-nasal trans-sphenoid surgery

Full Text:

PDF

References


Szolar D, Preidler K, Ranner G, Braun H, Kugler C, Wolf G, et al. The sphenoid sinus during childhood: establishment of normal developmental standards by MRI. Surgic Radiol Anatomy. 1994;16(2):193-8.

Adibelli ZH, Songu M, Adibelli H. Paranasal sinus development in children: A magnetic resonance imaging analysis. Am J Rhinol Allergy. 2011;25(1):30-5.

Antoniades K, Vahtsevanos K, Psimopoulou M, Karakasis D. Agenesis of sphenoid sinus. ORL. 1996;58(6):347-9.

Schatz CJ, Becker TS. Normal CT anatomy of the paranasal sinuses. Radiol Clinic North Am. 1984;22(1):107-18.

Simonetti G, Meloni F, Teatini G, Salvolini U, Rovasio S, Masala W, et al. Computed tomography of the ethmoid labyrinth and adjacent structures. Annals Otol Rhinol Laryngol. 1987;96(3):239-50.

Yune HY, Holden RW, Smith JA. Normal variations and lesions of the sphenoid sinus. Am J Roentgenol. 1975;124(1):129-38.

Banna M, Olutola PS. Patterns of pneumatization and septation of the sphenoidal sinus. J Canad Assoc Radiol. 1983;34(4):291-3.

Hamid O, El Fiky L, Hassan O, Kotb A, El Fiky S. Anatomic variations of the sphenoid sinus and their impact on trans-sphenoid pituitary surgery. Skull Base. 2008;18(01):009-15.

Abdullah BJ, Arasaratnam S, Kumar G, Gopala K. The sphenoid sinuses: computed tomographic assessment of septation, relationship to the internal carotid arteries, and sidewall thickness in the Malaysian population. J HK Coll Radiol. 2001;4:185-8.

Shah NJ, Navnit M, Deopujari CE, Mukerji SS. Endoscopic pituitary surgery-a. beginner’s guide. Indian J Otolaryngol Head Neck Surg. 2004;56(1):71-8.

Couldwell WT. Transsphenoidal and transcranial surgery for pituitary adenomas. J Neuro-oncol. 2004;69(1-3):237-56.

Idowu OE, Balogun BO, Okoli CA. Dimensions, septation, and pattern of pneumatization of the sphenoidal sinus. Folia Morphol. 2009;68(4):228-32.

Dündar R, Kulduk E, Soy FK, Aslan M, Kilavuz AE, Sakarya EU, et al. Radiological evaluation of septal bone variations in the sphenoid sinus. ENT Updates. 2014;4(1):6.

Sareen D, Agarwal AK, Kaul JM, Sethi A. Study of sphenoid sinus anatomy in relation to endoscopic surgery. Int J Morphol. 2005;23(3):261-6.

Jaworek JK, Troć P, Chrzan R, Sztuk S, Urbanik A, Walocha J. Anatomic variations of the septation within the sphenoid sinus on CT scan images-an initial report. Przeglad Lekarski. 2010;67(4):279-83.

Casiano RR. Anterior skull base resection. Endoscopic sinus surgery manual. Marel Dekker Inc, New York; 2002.

Unlu A, Meco C, Ugur HC, Comert A, Ozdemir M, Elhan A. Endoscopic anatomy of sphenoid sinus for pituitary surgery. Clinic Anatomy. 2008;21(7):627-32.

Cavallo LM, Messina A, Cappabianca P, Esposito F, de Divitiis E, Gardner P, et al. Endoscopic endonasal surgery of the midline skull base: anatomical study and clinical considerations. Neurosurg Focus. 2005;19(1):1-4.

Massoud AF, Powell M, Williams RA, Hindmarsh PC, Brook CGD. Trans-sphenoidal surgery for pituitary tumors. Arch Dis Child. 1997;76:398-404.

Nörovasküler PS. Surgical importance of neurovascular relationships of paranasal sinus region. Turkish Neurosurg. 2005;15(2):93-6.