How to Improve the Repair of Blast-Induced Perforations.

We wish to address the article entitled “Tympanoplasty Outcomes for Blast-Induced Perforations from Iraq and Afghanistan: 20072012” by Song et al. The authors retrospectively analyzed the healing outcome of tympanoplasty for 68 blast-induced tympanic membrane perforations (TMPs) and concluded that tympanoplasty can prove challenging in this population. The work is both excellent and interesting. However, some confounding factors affected the assessment of the healing outcome. In addition, with recent medical advances, some growth factor agents are now able to act as an alternative treatment strategy for blastinduced TMPs and thus avoid the need for tympanoplasty. The authors noted in the Materials and Methods section that “the lateral graft technique was typically used for total and neartotal perforations and was performed exactly as described by James Sheehy, except for the use of a ‘rosebud’ silk dressing instead of Gelfoam canal packing. Ofloxacin otic without topical steroids was used in all cases, and Gelfoam with ofloxacin was used to pack the middle ear and ear canal in all underlay cases. Mupirocin ointment was placed in the lateral ear canal in most cases.”We wish to highlight some confounding factors that affected the assessment of the healing outcome in this study. Previous studies have suggested that Gelfoam patching alone could repair large traumatic TMPs and small chronic TMPs with chronic suppurative otitis media. In addition, recent studies showed that the topical application of ofloxacin otic or antibiotic ointment kept the perforation edges moist and aided eardrum healing, thereby improving the closure rate of traumatic TMPs. The authors also found that bilateral perforations had poor healing outcomes in tympanoplasty for blast-induced TMPs. We speculate that these patients had poor eustachian tube function; the patients with a pathological eustachian tube are probably at high risk for a traumatic TMP. However, eustachian tube dysfunction is a predictive factor for the failure of temporalis fascia tympanoplasty. Thus, the authors should evaluate eustachian tube function prior to surgery in the future. Temporalis fascia tympanoplasty is usually adopted for blast-induced TMPs. However, recent studies have shown that the topical application of fibroblast growth factor 2 (FGF-2) accelerates the healing of large traumatic TMPs and subacute TMPs, including blast-induced TMPs, and shortens the closure time. Lou et al reported a closure rate of 94.1% for FGF2–repaired blast-induced total or near-total TMPs; this is an impressive result. It is important that both clinical and experimental studies have demonstrated that the exogenous application of FGF-2 can improve sensorineural hearing loss and protect cochlear neurons and hair cells from acoustic trauma. Another study also showed that FGF-2 repaired chronic TMPs with chronic suppurative otitis media and obtained a higher success rate. Thus, in the future, the authors might select FGF-2 to repair blast-induced TMPs.