Sinusitis refers to the inflammation that occurs in the mucous membrane or cavity of the sinuses. Clinically, the examination of sinusitis includes two aspects: one is the clinical examination, such as anterior rhinoscopy to inspect the nasal cavity, nasal endoscopy to inspect the nasal cavity, the opening of the sinuses, and the nasal passages; on the other hand, some imaging examinations can also be used, such as sinus CT examination, which is very important, and if necessary, sinus MRI can also be performed; there are also some other examination methods, such as nasal resistance examination, examination of sinus and nasal secretions, etc. Therefore, there are quite a few examination methods, among all the examination methods, the most important are the nasal endoscopy and sinus CT examination.