A. Etiology: Acute sinusitis to the nasal source of infection is common, the infection pathway is divided as follows: 1, the transnasal route nasal cavity a variety of diseases can cause sinusitis, but the main cause of acute rhinitis. 2, trauma maxillofacial trauma. 3, air pressure trauma air pressure changes sharply, the pressure in the sinus and the outside atmospheric pressure out of balance, such as the rapid descent of aircraft (dive), if the sinus mouth dysfunction so that the formation of negative pressure in the sinus, it will cause air pressure traumatic sinusitis. 4, infection of neighboring tissues or organs maxillary second bicuspids and 1~2 molars are closely related to the maxillary sinus floor wall. When the roots of these teeth are infected or the mucosa of the sinus is inadvertently damaged by tooth extraction, it can cause odontogenic sinusitis. Second, the main symptoms are as follows: 1, nasal congestion is persistent, still due to congestion and swelling of the nasal mucosa. The retention of purulent secretions in the nasal cavity can aggravate the symptoms of nasal congestion. 2.Sniffing disorder is caused by swelling of mucous membrane in nasal cavity, so that the particles of olfactory material cannot reach the olfactory area, and temporary smell disorder may appear. After the swelling of mucosa is eliminated, the sense of smell can be restored. Sieve sinusitis often makes the sense of smell significantly reduced or even lost. 3, increased nasal secretions secretions are mucopurulent or purulent, the amount is large. The anterior group of sinusitis is easily discharged to the anterior nostril, and part of it flows to the posterior nostril; the posterior group of sinusitis flows to the nasopharynx. The secretions are sometimes viscous and pus-like, often requiring forceful suction to remove, and the patient often has a sense of sputum. Odontogenic maxillary sinusitis, secretions often have a putrid smell. 4, headache and local pain acute sinusitis patient headache more heavy, often aggravated by coughing, head shaking or shaking. Three, treatment: should go to the regular hospital or specialist hospital treatment as soon as possible. Disease prevention: Exercise, enhance physical fitness, prevent colds, and actively treat acute rhinitis. Do not forcefully blow your nose when nasal secretions increase. Remove the lesion, correct the septum deformity, etc., can prevent the occurrence of sinusitis. When practicing swimming, you should learn the method of gas exchange to prevent choking and causing sinus infection.