Endoscopic Transcanal Technique for Treating Retraction Pockets of Pars Tensa
Director, Otolaryngology Department – Head and Neck Surgery, Shenzhen Sixth People’s Hospital, Shenzhen, China
Introduction: The main goal of this study is to assess the effectiveness of endoscopic transcanal tympanoplasty in improving hearing level and tympanic membrane condition for patients with retraction pockets of pars tensa (Grade IV and V).
Methods: Endoscopic transcanal tympanoplasty was performed on 42 ears of 37 patients with grade IV or V (by Sáde classification) retraction pockets of pars tensa. Composite tragal cartilage-perichondrium grafts were used to repair the retracted and perforated TM. Ventilation tubes were inserted in-surgery in 12 of 42 cases; 3-6 month post-surgery in 17 cases and no tube was inserted in 13 cases.
Discussion: 4-6 weeks after surgery, all patients were observed to obtain anatomically normal tympanic membranes. After an average follow-up period of 14.7 months, the mean air-bone gap had decreased from 31.4dB to 20.7Db in all patients. During the follow-up, recurrence of grade III retraction pockets was observed in 7 ears, in the posterosuperior and posterior positions. Ossiculoplasty was performed on all 42 cases and prosthesis extrusion was observed 2 ears of all patients with ossicular chain erosion.
Conclusion: The endoscopic transcanal tympanoplasty technique allows more direct access to the tympanic cavity and provides a wider view comparing to traditional microscopic approach. This enables surgeons to gain better views on blind corners where retraction pockets tend to occur. Simultaneous and post-surgical ventilation tube insertion have proven to help patients obtain better-ventilated middle ear cavity and improved hearing. In all, this endoscopic technique has proven to be effective in improving anatomic and functional reconstruction while ensuring a direct and easy-to-preform surgery.