Normal Anatomical Variants of the Paranasal Sinuses at Computed Tomography Scanning

Background: Recognition of PNS (Paranasal sinus) anatomic variants is particularly important in preoperative workup of patients with sinonasal pathology. CT (computed tomography) scanning can give exquisite details on sinus anatomy and pathology and is the main modality used to image the paranasal sinuses so the aim of the study isto evaluate certain anatomic variants of the paranasal sinuses in patients referred to the CT unit in Al-Immamain Al-Kadhymain Medical City. Patients and Method: We retrospectively analyzed the CT scans of the paranasal sinuses for patients referred to the CT unit in Al-Immamain Al-Kadhymain Medical City/Baghdad, Iraq for a period of 12 months . All the patients included in the study underwent standard CT scan of the PNS. Results: A net sample size of 188 was analyzed by the current study. Female: Male ration was (1.26:1).The incidence of septal deviation in the study sample was (51.06%) slightly more cases were deviated to the right (51.4%) than to the left (48.95%).Paradoxical middle turbinate’s were observed in(18.6%), middle turbinate aeration was observed in (58.5%) on the right and (53.1%) on the left. The incidence of variant air cells were as follows: Onodi (24.4%), Haller (11.1%), and Aggernasi (87.7%). Conclusion:The percent of most of the anatomical variants in our study sample was approximate to the percent published in the literature with the most common anatomic variants encountered being septal deviation followed by aerated middle turbinate’s whether unilateral or bilateral. The most frequent air cell was Aggernasi present in 87.7%.