CC-BY-NC-ND 4.0 · Int Arch Otorhinolaryngol 2018; 22(02): 161-166
DOI: 10.1055/s-0037-1607336
Original Research
Thieme Revinter Publicações Ltda Rio de Janeiro, Brazil

An Analysis of Anatomic Variations of the Sphenoid Sinus and Its Relationship to the Internal Carotid Artery

Myrian Marajó Dal Secchi
1  Department of Otorhinolaryngology, Faculdade de Ciências Médicas da Santa Casa de São Paulo, São Paulo, SP, Brazil
,
Ricardo Landini Lutaif Dolci
1  Department of Otorhinolaryngology, Faculdade de Ciências Médicas da Santa Casa de São Paulo, São Paulo, SP, Brazil
,
Reginaldo Teixeira
2  Department of Radiology, Irmandade da Santa Casa da Misericórdia de Santos, Santos, SP, Brazil
,
Paulo Roberto Lazarini
1  Department of Otorhinolaryngology, Faculdade de Ciências Médicas da Santa Casa de São Paulo, São Paulo, SP, Brazil
› Author Affiliations
Further Information

Publication History

03 April 2017

03 September 2017

Publication Date:
25 October 2017 (eFirst)

Abstract

Introduction The sphenoid sinus (SS) has a high variability; its anatomical relations and variations must be well understood prior to the expanded endoscopic surgery (EES) at the skull base via the endonasal transsphenoidal approach. A feared complication is injury to the internal carotid artery (ICA).

Objective To evaluate the anatomic variations of the SS and its relationship to the ICA using computed tomography (CT).

Methods Cross-sectional retrospective study. Analysis of 90 patients' CT scans on axial, coronal and sagittal planes with 1 mm slices, evaluating lateral and posterior extensions of pneumatization of the SS, deviation of the sphenoid septum, presence of septations and their relationship to the parasellar and paraclival segments of the internal carotid artery (psICA and pcICA, respectively).

Results The association between the protrusions of the psICA and the pcICA was statistically significant (p < 0.001), as was the association between the lateral extension of pneumatization of the SS and the protrusion of the psICA (p = 0.014). The presence of the posterior extension of pneumatization of the SS and protrusion of the pcICA occurred in 46% of the cases. Deviation of the sphenoid septum in the direction of the pcICA was present in 14% and dehiscence of the pcICA was seen in 3.6% of the cases.

Conclusion Using the CT scan to recognize the type of extensions of pneumatization of the SS, the deviation of the sphenoid septum, and the presence of septations is beneficial to identify accurately the ICA and to reduce the risk of injury to it.