CT scan can detect a variety of sinus lesions, as follows: 1, acute maxillary sinusitis: manifested as exudation and air-fluid flat in the maxillary sinus, such as chronic sinusitis often manifested as sinus mucosal thickening; 2, sinus trauma: clinical work encountered in patients with maxillofacial trauma, often makes the sinus 3, sinus tumor: the most common sinus tumor is maxillary sinus cancer, which usually manifests as a soft tissue mass in the maxillary sinus, and when the mass is small, the bone is not destroyed, but when the mass increases, it will destroy the bone of the sinus and even invade the surrounding structures.