ADENOIDS - AN ANATOMICAL REVIEW

The nasopharyngeal tonsils commonly called as - adenoids¿ is situated at the junction of the roof and posterior wall of nasopharynx. It develops from the ventral part of the second pharyngeal pouch by the fusion of the two lateral primordia. Adenoids are a midline structure, covered by pseudostratified ciliated columnar epithelium and arranged like a segment of orange in the roof of the nasopharynx. Like the palatine tonsils, the adenoid is regarded as a B-cell producing organ and its main function is production of IgA antibodies locally and IgG and IgM antibodies systemically. Antigens get trapped into adenoids during parabolic flow of air during inspiration which is called as Adenoid Sampling. The upper airway is a complex structure that is outlined by the soft tissues forming the nasopharynx and oropharynx within the skeletal boundaries of the mid and lower face. It undergoes morphologic change as a result of growth of the skeleton and surrounding tissues as well as functional changes throughout childhood.