Computer Tomographic study of Anatomic Variations of Paranasal Sinuses in Libyan Population and their Clinical Correlation

Introduction: In the era of Functional Endoscopic Sinus Surgery, precise knowledge of paranasal sinus anatomy and variations are essential for the surgeon. The multi-slice computed tomography is the imaging modality of choice provides accurate evictions of the anatomy, the anatomical variants and the extent of the disease in paranasal sinuses, such a method allowing their accurate identification with high anatomical details. Some of these variants may predispose to sinus diseases or become of high risk for injuries and complication during surgical procedure, therefore, the study of anatomic variants of paranasal sinuses is important in the preoperative endoscopic surgery. Objectives: The purpose of this study is to assess the frequency of anatomic variants and their clinical importance. Materials and methods: This retrospective study was conducted at the Department of Radiology, Benghazi Medical Center, Benghazi, Libya. Data comprised the paranasal sinus computed images of 112 patients (46 males and 66 females) analyzed for the presence of anatomic variants and associated sinus pathology. Results: Our results showed that the most common anatomical variants was deviated nasal septum (60.7%) with slight higher incidence on left side, followed by concha bullosa (22.3%), other variants found were absent frontal sinus (18.8%), Nasal spur (14.3%) , Agger nasi cell (16.1%), Haller cell (5.4%), Onodi cell (2.7%), accessory ostia of maxillary sinuses (10.7%), accessory middle nasal concha (1.8%), paradoxical middle turbinate (1.8%), nasal septum pneumatization (5.4%), Crista galli pneumatization (2.7%), pneumatization of hard palate (1.8%) and pneumatization of clinoid process (6.3%). (53.6%) patients suffered from sinusitis, the results showed that the most common sinus involved was maxillary sinus. Conclusion: Anatomical variations of PNS are quite common. Analysis of every paranasal CT scan obtained for sinusitis for the presence of different anatomic variants is of questionable value unless endoscopic surgery is planned to reduce the risk of intraoperative complications.