Multidetector Computed Tomography Study of Anatomical Variations of Ethmoidal Sinuses

Abstract

Introduction: Anatomical variations of ethmoidal sinuses are complex and surgically very important. Preoperative detection of these variants is important to prevent surgical complications. Multidetector Computed Tomography (MDCT) is the modality of choice for evaluation of these variants of ethmoidal sinuses. Aim: The present work was carried out to study the normal anatomical variations of ethmoidal sinuses by 128 slice MDCT. Materials and Methods: This was a retrospective analysis of paranasal sinuses in 500 cases by MDCT in adults. Axial images of Paranasal Sinuses (PNS) were taken by 128 MDCT, with patients in supine position. Axial images were further reconstructed in both coronal and sagittal planes to evaluate common variations of ethmoidal sinuses. Statistical analysis was done using SPSS version 20.0 and 95% Confidence Interval values (CI) were calculated for each variant of ethmoidal sinuses. Results: Present study shows agger nasi cells as the most common anatomical variant with 76.8% cases (95%CI:73.1-80.5), followed by frontal cells in 50.8% cases (95% CI:46.4-55.2), Haller cells in 41.2% (95% CI:36.9- 45.5), Onodi cells in 35.4% (95% CI:31.2-39.6), frontal bullar in 27.4% (95% CI:23.5-31.3), supraorbital cells in 19.2% (95% CI:15.7-22.6) and suprabullar cells in 14.4% cases (95% CI:11.3-17.5). Conclusion: Ethmoidal sinuses form a major component of paranasal sinuses that have high prevalence of anatomical variations. These cells are frequent causes for complicated sinus inflammatory pathologies and failed sinus surgeries. The surgeons must be aware of the anatomical variations to avoid untoward surgical complications and for better surgical outcome.

Keywords

• agger nasi
• frontal cells
• paranasal sinuses