Normal anatomic variants of paranasal sinus region studied by computed tomography


  • Shawnam Nasih Dawood Department of Surgery, College of Medicine, Hawler Medical University, Erbil, Iraq.



Anatomic variants, Paranasal sinuses, Computed tomography


Background and objective: Variation in paranasal sinus anatomy, as shown on computed tomographic scans, is of potential significance as it may pose risks during surgery or predispose to certain pathologic conditions. This study aimed to investigate the frequency of anatomic variants of the nasal cavity and paranasal sinuses in our population and determine their relationship with gender and find out the association of these variants with mucosal abnormalities.

Methods: This was a cross-sectional study conducted at the College of Medicine, Hawler Medical University from October 2017 to January 2019. A review of computed tomography scans of the paranasal sinuses of 300 patients was done; special attention was directed toward identifying bony anatomic variants and mucosal abnormalities.

Results: Frequent variants were: Agger nasi cells (72%), nasal septal deviation (71.7%), Haller cells (70.7%), concha bullosa (61%), elongation of uncinate process (69.7%) and different variants of the sphenoidal sinus (78.8%). The frequency of variants did not differ significantly with respect to gender, except for sphenoidal variants along with Keros types and asymmetry of the ethmoidal roof. A significant association was found between middle concha variants and inferior turbinate enlargement (P <0.001).

Conclusion: Anatomic variants of the paranasal sinus region were common in our population; the most frequent ones were those involving the nasal septum, ethmoid air cells, sphenoid sinuses, and middle turbinates. The study of these variants is important for the management of paranasal sinus region disease.


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How to Cite

Dawood, S. N. (2020). Normal anatomic variants of paranasal sinus region studied by computed tomography. Zanco Journal of Medical Sciences (Zanco J Med Sci), 24(2), 187–196.



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