Technical feasibility of endoscopic eustachian tube catheter placement: A cadaveric analysis

Background: Patulous eustachian tube (pET) can result in transmission of sound from the pharynx to the middle ear (ME) via an abnormally patent ET. The objective of this study was to evaluate the technical feasibility of a reversible transnasal procedure for pET using an occluded silastic catheter to close the ET. Methods: Ten sides were evaluated in five cadaver heads. Size 14, 16, and 18G catheters were occluded with bone wax to create a semirigid solid tube. They were placed transnasally, under endoscopic guidance through the ET orifice to span the entire ET length. Proper placement in the ME was confirmed by tympanotomy. Each attempt was graded on a four-point scale based on ease of placement: 3=, 2=, 1=, and 0. Results: The 16G was the easiest to place with the best fit and was confirmed in the ME in eight cases. The 14G catheter was next easiest to place and was observed in the ME in seven cases. It generally had an extremely tight fit and propensity to impart mucosal trauma. The 18G was the most difficult to place and was observed in the ME in six cases. The catheter was noted to displace easily because of a loose fit. Tympanic membrane or ossicular injury was not noted in any trial. Conclusion: These cadaveric data suggest that a semirigid catheter provides the technical capability to reversibly occlude the ET via the transnasal endoscopic route. Further confirmation is necessary in human studies to determine its effectiveness for management of pET.