Materials and Methods:

This retrospective cohort study followed STROBE guidelines. The patient inclusion process is detailed in Figure 1. All consecutive patients, aged < 18 years old, operated on between January 1998 and December 2012 for tympanic membrane (TM) perforation closure using a cartilage underlay technique were included. Patients had to have a one-year follow-up (including anatomical examination and audiometry workup) and have no history of ipsilateral ear surgery (except for ventilation tubes). Medical files of all perforations were reviewed using FileMaker Pro (Claris, Santa Clara, California, USA) and per, perioperative and surgical data was analysed. Patient age at surgery, sex and comorbidities (allergy, cleft palate, craniofacial anomaly) were noted. Also, perforation size, location, surgical technique, expertise of the surgeon (junior surgeon or senior paediatric otologist), status of the contralateral ear and perioperative observations (mucosa inflammation, glue in the middle ear) were noted. The following postoperative information was noted: TM closure, myringitis, otitis media with effusion (OME), TM retraction, cholesteatoma, external auditory canal stenosis. Audiometric tests, air and bone conduction, mean air-bone gap, were reported using the pure-tone average (PTA) referring to the average of hearing threshold levels at 500, 1000, 2000 and 4000Hz. Statistical analysis was made using R software (http://cran.r-project.org/). Data was described as mean ± standard deviation or median [interquartile range] for quantitative variables and frequencies (%) for qualitative variables. Comparisons for continuous data were performed through Student test or Wilcoxon rank test and for categorical data through Pearson’s Chi-squared test or Fisher’s Exact Test. Statistical tests were two-sided and p values less than 0.05 were considered statistically significant. This is a retrospective study and has been approved by our local Institution Review Board (IRB). The study was registered on the Clinical Trials Database (NCT02296944). In compliance with French law, a letter of no objection was sent to all participants if they were adults or otherwise their parents. The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.