This book gives an insight into role of Multi Slice Computed Tomography (MSCT) in detection of lesions of Para Nasal Sinuses (PNS). MSCT has revolutionized the imaging of PNS. Before the advent of CT plain radiography had limited role in evaluation of PNS lesions. MSCT not only shows the bony details better but also gives details of soft tissue densities. Evaluation in axial, sagittal and coronal planes adds to the imaging findings. In our study we have evaluated 50 cases of patients with PNS complaints and have got of spectrum of interesting CT findings. Lesions included traumatic, inflammatory, infective and neoplastic pathologies. Representative images have been provided for clinical correlation.