The adenoid, also known as the pharyngeal tonsil or lymphoid tissue, is located at the top of the nasopharynx and the posterior pharyngeal wall. It looks like an orange segment and is most active in growth from ages 2 to 6 in children, gradually atrophying after age 10. Due to repetitive inflammation, the adenoid can undergo pathological hyperplasia, known as adenoid hypertrophy, which can cause clinical symptoms such as nasal congestion and mouth breathing. The main cause of adenoid hypertrophy is inflammation in the nasopharyngeal region or the adenoid itself. Repeated stimulation leads to pathological hyperplasia. Common causes include recurrent acute and chronic nasopharyngitis, various acute infectious diseases in childhood, which exacerbate nasal congestion symptoms, obstruct nasal drainage, and nasal and sinus secretions further stimulate the adenoid, causing it to continue to grow and creating a vicious cycle.