Transtympanic microendoscopy of the eustachian tube: a new approach method

The eustachian tubes (ET) of sixteen patients suffering from chronic otitis media or otitis media with effusion were observed transtympanically by using an 0.85mm tip-controllable fiberoptic microendoscope. The examination was accomplished under local anesthesia. The osseous portion of ET was endoscopically accessible and was usually found patent in most patients. Similar to findings of the cadaveric temporal bone studies, a collapsed wall was observed in the lumen of isthmus and valve section of cartilaginous ET. The parapharyngeal section of cartilaginous ET, however, was found to include an open lumen, where pulsatile movements of the medioinferior membranous ET wall could be seen. In addition, special endoscopic findings of the ET lumen in different patients including relatively narrow isthmus, mucus accumulation, edematous mucosa, intraluminal tumor invasion, opening failure of valve section, etc. were also observed. Despite the technical difficulties involved, transtympanic ET microendoscopy is a potentially useful technique for exploring the physiology and pathophysiology of ET.