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Identification of Significant Anatomical Variations in the Nose and Anterior Skull Base Using Computed Tomography: A
Naureen Farhan1, Syeda Uzma Naqvi2, Binish Rasheed1
1Diagnostic Radiology, Dow Institute of Radiology, Dow University of Health Sciences, Karachi, PAK.
Abstract:
Introduction This study is aimed at the identification of anatomic variations in the nose, paranasal sinuses (PNS), and anterior skull base, which are substantially important to ensure safe and complete endoscopic sinus and skull base surgery. Materials and methods This cross-sectional study was conducted at the Dow Institute of Radiology, Dow International Medical College, Dow University Hospital. We included adult patients (i.e., those aged 18 years or older) undergoing a non-contrast CT of the nose and PNS. Two consultant radiologists reviewed the scans on the picture archiving and communication system independently. Any conflict was resolved with consensus. Anatomical variations in the nose, PNS, and anterior skull base of both sides were evaluated. Results We reviewed the CT of the PNS of 130 patients with an age of 35.8 ± 14.48 years (mean ± standard deviation). The proportion of men (64/130; 49.2%) and women (66/130; 50.8%) was equal. All patients had one or more variations. The most common abnormality was a deviated nasal septum (DNS), observed in 115 of 130 participants (88.5%) with unilateral occurrence predominant. It was followed by inferior nasal turbinate hypertrophy and agger nasi cells in 76.2% and 67.7% patients, respectively. Optic nerve variation type I (160/260 sinuses; 61.5%) and Keros type II, for olfactory depth (162/260 sinuses; 62.3%), were most common. Conclusions Here we report anatomical variations in PNS in all patients of our study; the commonest of all anatomical variations was a DNS. A CT scan is instrumental in surgical planning and patient safety in functional endoscopic sinus surgery.
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