Computed tomography anatomy of the paranasal sinuses and anatomical variants of clinical relevants in Nigerian adults

Aim: The aim of the study is to show the anatomy of the paranasal sinuses as delineated by the computed tomography and to describe the variants which not only predispose to chronic sinusitis but may lead to complications in endoscopic sinonasal surgery. Introduction: The paranasal sinuses are group of air filled spaces surrounding the nasal cavity. Paranasal sinuses start developing from the primitive choana at 25–28 weeks of gestation. Three projections arise from the lateral wall of the nose and serve as the beginning of the development of the paranasal sinuses. Materials and methods: This was a prospective study carried out in a tertiary institution. 110 patients without paranasal sinus symptoms who presented for head computed tomography studies and gave consent for a coronal section scan of the paranasal sinuses to be taken in addition to the axial section of the head were included in the study. The CT examination was performed with GE Hispeed-NX/I Base-2002 Dual Slice Helical Computed tomography machine. Results: There were 48 females and 62 males giving a male female ratio of 1:1.3. Among these 229 cases of anatomical variants were observed. The commonest anatomical variants were pneumatisation of the middle nasal turbinates (32.73%). This is followed by agger nasi cells 23.64%, Haller’s cells 20.91%, septal deviation 20.18% and sphenoid sinus septation (18%). Conclusion: Computed tomography is the gold standard in the radiologic investigation of the paranasal sinuses, either for diagnosis for sinonasal lesions or pre and post-surgical assessment. Its capability in delineating the anatomical variants in paranasal sinuses protects against iatrogenic injury to essential structures around the paranasal sinuses and recurrent diseases from extramural cells