Patients have symptoms of nasal obstruction while sleeping, the specific reasons are as follows: 1, inflammatory factors: patients are often due to inflammatory infectious and allergic disease factors of the nasal cavity, sinuses, resulting in congestion, swelling, edema of the nasal cheek mucosa, will cause the nasal breathing passages become narrower, or even near complete blockage of the situation, causing a significant increase in respiratory ventilation resistance, resulting in a more obvious nasal congestion symptoms. Especially at night when sleeping, the body is in a lying position, the congestion, swelling and edema of the nasal mucosa is often more serious than during the day, leading to further aggravation of the symptoms of nasal congestion. 2, local morphological abnormalities: some patients may have a significant deviation of the nasal septum, the presence of polyps and other abnormal growths in the nasal tract, if necessary, further detailed examination is required.