Radiologic Evaluation of Paranasal Sinus Anatomical Variations: A Systematic Review of CT and CBCT Studies and Their Surgical Implications
Radiologic Evaluation of Paranasal Sinus Anatomical Variations: CT and CBCT Studies
DOI:
https://doi.org/10.54393/pjhs.v6i12.3557Keywords:
Paranasal Sinus Anatomical Variation, Onodi Cell, Keros Classification, CBCT, Surgical RiskAbstract
Anatomical variations of the paranasal sinuses may influence surgical safety and outcomes in endoscopic sinus and skull-base procedures. This review compiles radiologic evidence to quantify variant prevalence and delineate surgical significance. Objectives: To evaluate computed tomography (CT) and cone-beam computed tomography (CBCT) studies for the prevalence, morphology, and clinical relevance of paranasal sinus anatomical variations, emphasizing their implications for endoscopic sinus and skull-base surgery. Methods: A systematic search of PubMed, Scopus, and Cochrane databases (January 2010–March 2025) was conducted following PRISMA 2020 guidelines. A total of 612 articles were screened, and 17 studies fulfilled the inclusion criteria. Eligible studies included original human CT or CBCT analyses reporting prevalence or morphology of variants (Onodi, Haller, Keros, accessory maxillary ostium [AMO], and roof asymmetry) with relevant surgical commentary. Weighted means were derived from pooled prevalence data across comparable imaging modalities using frequency-based aggregation. Study quality was evaluated using QUADAS-2 and modified Newcastle–Ottawa scales. Results: Seventeen studies were included. Weighted mean prevalence values were Onodi 34%, Haller 45%, and AMO 42%, with deep Keros type III fossae present in 5–9%. Ranges reflect inter-study heterogeneity in imaging protocol and cohort size. Radiology-guided findings highlighted optic-nerve proximity in Onodi, cribriform vulnerability in Keros III, orbital risk with Haller cells, mucus recirculation with AMO, and corridor distortion from concha bullosa or ethmoid-roof asymmetry. Conclusions: Anatomical variants of surgical relevance are frequent and population-dependent. Structured radiologic reporting using CT or CBCT improves pre-operative planning, mitigates optic-nerve and skull-base risks, and enhances procedural safety.
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