Natural nasal–esophageal fiberscopy in the COVID-19 pandemic—preventing sneezing without anesthesia: a case report

Abstract
Background We are laryngologists. We observe natural phonatory and swallowing functions in clinical examinations with a trans-nasal laryngeal fiberscope (TNLF). Before each observation, we use epinephrine to enlarge and smooth the common nasal meatus (bottom of nostril) and then insert a wet swab inside the nose, as in taking a swab culture in the nasopharynx. During the current COVID-19 pandemic situation, this careful technique prevents any complications, including nasal bleeding, painfulness, and induced sneezing. Here, we introduce our routine to observe esophageal movement in swallowing in a natural (sitting) position without anesthesia. Case presentation The case was a 70-year-old female who complained that something was stuck in her esophagus; there was a strange sensation below the larynx and pharynx. After enlarging and smoothing the common nasal meatus, we inserted the TNLF (slim type ⌀2.9 mm fiberscope, VNL8-J10, PENTAX Medical, Tokyo, Japan.) in the normal way. We then observed the phonatory and swallowing movements of the vocal folds. As usual, to not interfere with natural movements, we used no anesthesia. We found no pathological condition in the pyriform sinus. We asked the patient to swallow the fiberscope. During the swallow, we pushed the TNLF and inserted the tip a bit deeper, which made the fiberscope easily enter the esophagus, like in the insertion of a nasogastric tube. We then asked the patient to swallow a sip of water or saliva to clear and enlarge the lumen of the esophagus. This made it possible to observe the esophagus easily without any air supply. With tone enhancement scan, the esophagus was found to be completely normal except for glycogenic acanthosis. Conclusions The advantage of this examination is that it is easily able to perform without anesthesia and with the patient in sitting position. It is quick and minimally invasive, enabling observation the physiologically natural swallowing. It is also possible to observe without anesthesia down to the level of the esophagogastric junction using with a thin type flexible bronchoscope. In the future, gastric fiberscopes might be thinner, even with narrow band imaging (NBI) function. Before that time, physicians should remember to just insert along the bottom of the nose.