Adenoid surgery is relatively safe and usually has no sequelae. However, all surgeries have certain risks. Complications or sequelae of adenoid surgery may include localized hyperplasia, nasopharyngeal stenosis, blockage of the Eustachian tube and so on. 1. Localized hyperplasia: Most of the adenoids are located in the posterior pharyngeal wall. Surgery results in residual adenoids, which, combined with long-term inflammatory stimulation, can cause localized hyperplasia after surgery. 2. Nasopharyngeal stenosis: Surgical resection leads to the formation of local scar tissue, which causes local tightness or discomfort in the nasal cavity. 3. Eustachian tube blockage: The process of adenoid surgery may damage the opening of the Eustachian tube, which in turn may produce the sequelae of Eustachian tube blockage, tinnitus as well as hearing loss and other symptoms. It is recommended that patients undergoing adenoid surgery should go to the hospital for diagnosis and treatment by a specialized physician.