Autonomic Reflexes With Epipharyngeal Abrasive Therapy (EAT)

A literature review was conducted of epipharyngeal abrasive therapy (EAT) in the treatment of chronic epipharyngitis, focusing on the mechanism of action by autonomic nerve stimulation. The mechanism of action of EAT in stimulating the immune system has recently become clear. However, the mechanism of action of EAT on the autonomic nervous system remains to be elucidated. The purpose of this paper is to provide insight into the still not fully understood mechanism of EAT stimulation of the autonomic nervous system in chronic epipharyngitis by collecting and integrating previous studies and papers focusing on the autonomic nerve stimulating effects of EAT. The EAT stimulates a network of brainstem neurons involved in swallowing, vomiting, breathing, and circulatory centers, and further affects endocrine reflexes via the hypothalamus and pituitary, and stress responses via the limbic system. The EAT reflex is hierarchically integrated and is thought to reflexively control not only the pharyngeal reflex but also autonomic functions such as airway, breathing, cardiovascular, cerebral circulation, digestive, and endocrine glands. The immune system, endocrine system, and autonomic nervous system are thought to interact with each other to produce the therapeutic effect of EAT. It is important to determine which mechanism is predominantly involved in each case of chronic epipharyngitis and to utilize it in treatment. Elucidating the mechanism of action of EAT autonomic nerve stimulation will be an important guideline in determining the treatment strategy for chronic epipharyngitis.