For two consecutive days, a three year old girl sat up in the middle of the night and said, 'Mom, someone is sweeping the floor.' She was diagnosed with secretory otitis media. Two weeks later, after a follow-up examination, the middle ear effusion relieved. The question was, "Is there anyone else sweeping the floor?" The answer was, "No more sweeping." The six year old boy told his mother two consecutive days before going to bed and in the middle of the night that his ears were buzzing. His mother was shocked and quickly took him to the otolaryngology department for treatment. The doctor's physical examination and hearing test showed no abnormalities, so he explained the condition to the parents. The little boy immediately said to his mother, "I told you, there are too many mosquitoes and I haven't cleaned them up. Look at the bag on my leg." The mother covered her face and smiled, complaining that her son had irreversible hearing loss caused by secretory otitis media from a young age, thinking that his son also had the same disease. The above two stories are both based on the real medical records of Wang Xiaoya, a young and middle-aged doctor with strong medical strength in Guangdong and the deputy chief physician of the Otolaryngology Department of Guangzhou Women and Children's Medical Center, both involving the disease of secretory otitis media. Ninety percent of preschool children have had this disease at least once, and although the symptoms are not obvious, it may cause irreversible hearing loss. Children should seek timely medical attention if they ignore others or hear "strange sounds". Secretory otitis media refers to a type of disease where there is fluid accumulation in the middle ear, often without obvious acute inflammation. In other words, its occurrence is often very hidden, and there are no common symptoms of otitis media such as ear pain and fever. The most common clinical manifestation is mild to moderate hearing loss, and this group of children may exhibit difficulty hearing when others speak softly, Or when they are more focused, they may show insensitivity to the sounds in their surroundings. For example, when their parents or teachers talk to them while playing with toys or focusing on something, they may not react well or respond well; or when they talk to them, they always ask back, 'What are you talking about?' "Wang Xiaoya said. Some children may experience tinnitus, but the sound they hear may vary. Some children may hear a "rustling" sound in their ears, just like the little girl in the above case who heard "someone sweeping the floor"; Some may hear the sound of blowing or mosquitoes buzzing. For children with cleft lip and palate or Down's syndrome, due to congenital facial structures, persistent and unrelieving secretory otitis media can easily occur from birth. If it persists during critical periods of language development, it can show significant language development delay. When a child experiences hearing loss or special sounds in their ears, it is necessary to promptly seek medical attention. More than 90% of preschool children have at least one case of secretory otitis media. The incidence rate of secretory otitis media among preschool children is very high. Some studies show that more than 90% of preschool children have at least one case of secretory otitis media. Wang Xiaoya introduced that many kindergartens in Guangzhou now conduct hearing screening for young children using acoustic immittance testing, which can reflect the function of the middle ear. In clinical practice, it is common to encounter children who experience hearing loss during screening and are diagnosed with secretory otitis media upon examination. This is related to two factors: on the one hand, our nose and ears are connected through the eustachian tube, which is thicker, shorter, and flatter in children