Abstract
Background: We are laryngologists, to observe natural phonatory and swallowing functions, in every clinical examination with trans-nasal laryngeal fiberscope (TNLF), before the observation, we use epinephrine to enlarge and smoothen inside common nasal meatus (bottom of nostril), then insert wet swab inside the nose, like a swab culture in nasopharynx. In particular current COVID-19 pandemic situation, this careful technique prevents any complications even nasal bleeding, painfulness, and inducing sneezing. Here we introduce our routine to observe esophageal movement in swallowing in natural setting (sitting position) without anesthesia.Case presentation: A case was 70-year-old female who complained something stuck esophagus or strange sensation below the larynx and pharynx. After enlarge and smoothen inside common nasal meatus we insert the TNLF (slim type ⌀29mm fiberscope, VNL8-J10, PENTAX Medical, Tokyo, Japan.) in a same way. Then observe the phonatory and swallowing movement of vocal folds. To get natural movements we had never used any anesthesia. There was no pathological condition in the pyriform sinus, we asked a patient to swallow the fiberscope. At that timing we push the TNLF and insert the tip a bit deeper simultaneously with swallowing, which make the fiberscope easily enter the esophagus like the insertion of nasogastric tube. Then asked the patient to swallow sip of water or saliva, the lumen of esophagus cleared and enlarged. This makes to observe esophagus easily without any air supply. The esophagus is completely normal except glycogenic acanthosis with tone enhancement scan. Conclusions: The advance point of this examination is easily able to perform in sitting position without anesthesia, also takes only a minute and minimum invasive to observe the physiologically natural swallowing. It is also possible without anesthesia until esophagogastric junction using with a thin type flexible bronchoscopy. In the future, diameter of gastric fiberscope even with narrow band imaging (NBI) function might be gradually getting thinner. Before that time every physician should know this technique. Just insert along the bottom of nose.
Measurements of the aero-acoustic properties of the vocal folds and vocal tract during phonation into controlled acoustic loads
