Comparison of Underlay and Overlay Techniques With Perichondrium in Endoscopic Myringoplasty to Repair Chronic Perforation.

ObjectiveThis study was performed to analyze the clinical effect of tragus perichondrium in endoscopic myringoplasty with underlay and overlay techniques for the repair of chronic tympanic membrane (TM) perforation.Subjects and MethodsA total of 120 patients with chronic otitis media who underwent endoscopic TM repair with tragus perichondrium were analyzed. The cases were randomly divided into an overlay group (n=60) and an underlay group (n=60). The intraoperative duration, intraoperative blood loss, graft uptake rate, postoperative TM morphology, hearing outcomes and postoperative complications were compared between the two groups.ResultsOperative time and mean estimated blood loss were significantly lower in the underlay group than in the overlay group (χ2=4.82, p=0.0475)). At 12 months postoperatively, the overall graft uptake rate was significantly higher in the overlay group (98.4%) than in the underlay group (89.3%) (χ2=3.914, p=0.0281. 2 cases were found to have the formation of epithelial cholesteatoma bead in the overlay group, In addition, there were no significant differences between the two groups in the pre- or postoperative mean air-bone gap (postoperative air-bone gap: 11.25±2.71dB for underlay vs. 10.92±3.89dB for overlay, p=0.652). CT examination revealed no cholesteatoma in the middle ear.ConclusionsIn the treatment of chronic TM perforation, endoscopic tragus perichondrium overlay myringoplasty improves the graft success rate compared to the underlay technique. However, the probability of the formation of epithelial cholesteatoma bead will increase, and it requires a higher level of surgical precision. The underlay method is less invasive,takes less surgical time, and is easier to master than the overlay method.