Ossicular chain reconstruction in chronic otitis media: hearing results and analysis of prognostic factors

Abstract Introduction The goal of ossiculoplasty is to improve hearing and the success of this procedure depends on several factors. Objective Analyze the hearing results in patients with chronic otitis media undergoing ossicular chain reconstruction, as well as predictive factors for successful surgery. Methods Charts of patients undergoing ossiculoplasty between 2006 and 2016 were reviewed. Sixty-eight patients were included, totaling 72 ears. The following data was analyzed: gender, age, smoking status, laterality, pathology, audiometric exams, type of surgery, previous surgery, characteristics of the middle ear, otorrhea and ossicular chain status. Patients were also classified according to two indices: middle ear risk index and ossiculoplasty outcome parameter staging. The results were evaluated by comparing the air-bone gap before and after surgery. The success of reconstruction was defined as air-bone gap ≤20 dB and the improvement of speech reception Thresholds, calculated through the mean frequencies 0.5, 1, 2 and 3 kHz. Results Reconstruction success rate was 61%. The mean preoperative air bone gap was 34.63 dB and decreased to 17.26 dB after surgery. There was a correlation between low risk in middle ear risk index and ossiculoplasty outcome parameter staging indices with postoperative success. The most frequently eroded ossicle was the incus and the type of prosthesis most used was tragal cartilage. In the patients without incus, we achieved success in 74.2% of the surgeries. In the absence of the stapes, the success rate decreased to 63.3%. In the absence of the malleus, 85% of the patients had and air bone gap ≤20 dB. Conclusion We achieved good audiometric outcomes in ossiculoplasty and the results are comparable to other centers. Ossicle status influenced postoperative results, especially in the presence of stapes. We also concluded that the indexes analyzed may help to predict the success of the surgery.摘要 引言 听骨链成形术（ossiculoplasty）的核心目标为改善听力，该手术的成功与否受多种因素影响。 目的：分析接受听骨链重建术（ossicular chain reconstruction）的慢性中耳炎（chronic otitis media）患者的听力结局，并探究手术成功的预测因素。 方法：回顾性分析2006至2016年间接受听骨链成形术的患者病历，共纳入68例患者，合计72耳。本次研究分析的资料包括：性别、年龄、吸烟状态、患耳侧别、病理类型、听力学检查结果、手术方式、既往手术史、中耳特征、耳漏情况及听骨链状态。此外，依据两项指数对患者进行分组：中耳危险指数（middle ear risk index）与听骨链成形术结局参数分期（ossiculoplasty outcome parameter staging）。通过对比手术前后的气骨导差（air-bone gap）评估手术疗效，以气骨导差≤20 dB且言语接收阈值（通过0.5、1、2、3 kHz平均频率计算）得到改善作为手术成功的判定标准。 结果：本次研究的听骨链成形术总成功率为61%。术前平均气骨导差为34.63 dB，术后降至17.26 dB。中耳危险指数低风险、听骨链成形术结局参数分期与术后手术成功呈显著相关性。最常出现侵蚀的听骨为砧骨（incus），临床最常用的假体材料为耳屏软骨（tragal cartilage）。在砧骨缺失的患者中，手术成功率达74.2%；当镫骨（stapes）缺失时，手术成功率降至63.3%；而锤骨（malleus）缺失的患者中，有85%的受试者术后气骨导差≤20 dB。 结论：本研究中听骨链成形术取得了优良的听力学结局，相关结果与其他医学中心的报道相近。听骨状态可显著影响术后结局，尤以镫骨结构异常时最为明显。此外，本研究分析的两项指数可辅助预测手术成功的可能性。