Transnasal esogastroduodenoscopy (EGD): comparison with conventional EGD and new applications.

Technical improvements have allowed to significantly reduce the diameter of endoscopes used to examine the upper gastrointestinal tract. Hence, transnasal introduction of endoscopes used to perform a standard esogastroduodenoscopy (EGD) has become possible. Transnasal EGD (T-EGD) is better tolerated by patients than conventional EGD (C-EGD), and it presents the advantage of requiring no sedation in most patients (and, consequently, to reduce associated costs). However, the reduction in endoscope diameter has been obtained at the expense of a somewhat inferior image quality and a smaller biopsy channel diameter. Specific diagnostic and therapeutic applications taking advantage of the transnasal approach have also recently emerged (e.g., cholangioscopy placement of feeding tubes or of nasobiliary drains). The technique, feasibility, patient tolerance to unsedated procedure, diagnostic accuracy, costs, and novel therapeutic applications of T-EGD are reviewed.