Chronic sinusitis includes fungal sinusitis, allergic sinusitis, purulent sinusitis, etc. According to different classifications, different treatment plans should be developed, and the specific treatment principles are as follows: 1. allergic sinusitis: local nasal spray hormone drugs can be used, or oral anti-leukotriene drugs or antihistamines for systemic treatment; 2. fungal sinusitis: surgery is the only option; 3. purulent sinusitis: mostly caused by local obstruction such as deviated nasal septum and enlarged turbinates, which requires minimally invasive sinus surgery to restoration of patency.