Sinus mucosal thickening refers to the thickening of the maxillary sinus mucosa, and the main causes are divided into physiologic and pathologic. Physiological maxillary sinus mucosal thickening has no effect on the body, and pathological maxillary sinus membrane thickening may be inflammation, cysts, malignant tumors triggered by maxillary sinus mucosal thickening. It is recommended that people go to the hospital for further examination to clarify the specific cause of the disease and treatment. 1. Physiological factors: some people have congenital thickening of the maxillary sinus, which generally has no effect on the body. 2. Pathological factors: people may suffer from maxillary sinusitis due to inflammation, which causes thickening of the maxillary sinus, headache and other uncomfortable symptoms. In addition, when the maxillary sinus mucosal cysts, will also trigger the maxillary sinus thickening. If people suffer from maxillary sinus tumor, CT will also show maxillary sinus thickening.