Anatomy and physiology of the palatine tonsils, adenoids, and lingual tonsils

Objective: This review aims to discuss the basic anatomy and physiology of the palatine and pharyngeal tonsils, with reference to how this foundational understanding may affect patient management and surgical procedures in these regions of the upper airway. Methods: A literature search was performed using PubMed and Google Scholar using the MeSH terms tonsils, adenoids, anatomy, physiology, and adenotonsillectomy. Primary sources were excluded if they were abstracts only, non-English language, or non-human studies. Thirty-five sources were included in this review. Results and conclusions: The pharyngeal and palatine tonsils are compact yet physiologically complex mucosa-associated lymphoid tissues that make up a portion of Waldeyer's ring. As part of the mucosal immune system, these structures function in exogenous antigen sampling and stimulation of immune responses. Aberrant immune activation and/or regulation can lead to a myriad of pathologies, with adenotonsillar hypertrophy, chronic tonsillitis/adenoiditis, and recurrent otitis media among the most commonly encountered conditions by otolaryngologists. While the pathophysiology of these conditions is still incompletely understood, current evidence and future investigations may reveal patterns amenable to targeted medical management. When medical management fails, tonsillectomy and/or adenoidectomy may be indicated for patient care. Though routine procedures, the execution of tonsil and/or adenoid removal requires a thorough understanding of the anatomy of these lymphoepithelial organs so as to minimize the risk for rare serious complications that can occur. Copyright (c) 2021 Chinese Medical Association. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).