Anatomical variations are not diseases and can be present in every individual. Because of presence of these anatomical variations nearby anatomical relations of that structure changes. By considering the vast range of variations in the anatomy, every para-nasal sinus case should be planned carefully to avoid dreadful complications of surgical procedures. Variations in intranasal and sinus anatomy have been implicated in the etiology of chronic and recurrent sinusitis, and CT imaging has become an important diagnostic tool. Functional endoscopic sinus surgery has popularized the use of telescopes and has emphasized the importance of nasal endoscopy and computed tomography in the evaluation of patients with diseases of the nose and paranasal sinuses. The objective of this study is to determine anatomical variations of paranasal sinuses on CT scan and its assistance in Functional Endoscopic Sinus Surgery (FESS)