From NBCI:
An ultrathin endoscope inserted via a nostril, so-called transnasal esophagogastroduodenoscopy (TN-EGD) is widely accepted nowadays. Pain tolerance and safety seem to be the greatest advantage of TN-EGD when compared to those of a conventional procedure. There is no need for conscious sedation in TNE, and thus requires less patient monitoring, nursing time, and expenses.
Read more form NBCI…