Pretreatment factors affecting traumatic tympanic membrane regeneration therapy using epidermal growth factor.

Objective: The use of epidermal growth factor (EGF) to achieve closure of human traumatic tympanic membrane perforations (TMPs) was recently reported. However, pretreatment factors affecting healing outcomes have seldom been discussed. This study was performed to evaluate pretreatment factors contributing to the success or failure of TMP healing using EGF.

Design And Participants: This was a retrospective cohort study of 95 TMPs who were observed for at least 6 months after EGF treatment. Eleven factors considered likely to affect healing outcome were evaluated by univariate and multivariate logistic regression analyses.

Interventions: Each traumatic TMP was treated by daily topical application of EGF. The main outcome measures were complete closure versus failure to close and mean closure time.

Results: A total of 95 patients were included in the analyses. The total closure rate was 92.6% at 6 months, and the mean closure time was 10.5 ± 4.8 days. The closure rate was not significantly different according to the duration of perforation ≤3 days and >3 days (P = 0.816). However, the mean closure time was significantly different according to the duration of perforation (P < 0.001). The perforation size did not affect the closure rate (P = 0.442). The mean closure time in the low-dose EGF group was significantly shorter than that in the high-dose EGF group (P = 0.001). Logistic regression analyses showed that perforations with preexisting myringosclerosis were more likely to fail to close compared to those without preexisting myringosclerosis (P = 0.001). Multivariate logistic regression analyses showed that the duration of perforation (P = 0.011), size of perforation (P < 0.001), and involvement of the malleus in perforation (P = 0.005) were factors independently correlated with closure time.

Conclusions: Daily application of EGF can be used to treat all traumatic TMPs. The size of the perforation and inverted edges did not affect the closure rate, and the most beneficial dosage was sufficient to keep the eardrum moist. Multivariate logistic regression analyses revealed a significant correlation between preexisting myringosclerosis and failure to heal. Nevertheless, the size of perforation, starting time of application, and malleus injury were independent prognostic factors for prolonged healing time.