Flexible Endoscopic Evaluation of Swallowing with Sensory Testing

Flexible Endoscopic Evaluation of Swallowing with Sensory Testing (FEESST), or laryngopharyngeal sensory testing, is a technique used to directly examine motor and sensory functions of swallowing so that proper treatment can be given to patients with swallowing difficulties to decrease their risk of aspiration (food and liquids going into the lungs instead of the stomach) and choking. FEESST was invented by Dr. Jonathan E. Aviv MD, FACS in 1993, and has been used by otolaryngologists (ear, nose and throat doctors), pulmonologists (lung doctors), gastroenterologists (stomach and digestion doctors), intensivists (intensive care specialists) and speech-language pathologists for the past 20 years.FEESST is an outpatient procedure involving the passing of a thin flexible scope through the nose to the pharynx. The exam consisting of two parts. First part assesses sensation in the pharynx and airway protection. The airway protection is assessed by sending air-pulses to the throat area that is innervated by the vagus nerve, which is the region of the throat between the top of the vocal folds to the tip of the epiglottis in order to stimulate an airway protective reflex called the laryngeal adductor reflex (LAR). This reflex, which occurs when the tissues of the throat are stimulated, causes the vocal folds to close in order to protect the airway from food going into the lungs. Since the windpipe (trachea) is located so close to the food-pipe (esophagus) this is a critical reflex to be functioning well at all times. Stimulation of this reflex not only results in protection of the airway, it also initiates a swallow. When a swallow is initiated the larynx rises up to two inches, going further away from the esophagus, thereby acting as an additional cover for the airway.Over the past 20 years, primarily due to work with sensory testing performed by gastroenterologists (stomach doctors) and pulmonologists (lung doctors), sensory testing and FEESST have been shown to have additional applications beyond assessing swallowing function.