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 听骨链成形术(ossiculoplasty)的核心目标为改善患者听力，该手术的成功结局受多重因素共同影响。 研究目的 分析慢性中耳炎(chronic otitis media)患者接受听骨链重建术(ossicular chain reconstruction)后的听力预后情况，并探寻手术成功的预测因子。 研究方法 回顾性分析2006年至2016年间接受听骨链成形术的患者临床病历，共纳入68例患者，共计72耳。本次研究分析的资料涵盖：性别、年龄、吸烟状态、患耳侧别、病变类型、听力学检查结果、手术方式、既往手术史、中耳局部特征、耳漏情况及听骨链状态。此外，依据两项指标对纳入患者进行分层：中耳风险指数(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，将重建成功定义为术后气骨导差≤20 dB且言语接受阈(speech reception threshold)得到改善，其中言语接受阈通过0.5、1、2、3 kHz四个频率的均值计算得出。 研究结果 本次研究的听骨链重建总成功率为61%。术前平均气骨导差为34.63 dB，术后平均气骨导差降至17.26 dB。中耳风险指数及听骨链成形术结局参数分期评分较低的患者，其术后手术成功率更高，两项指标均与手术成功存在显著相关性。临床中最常出现侵蚀的听骨为砧骨，最常用的假体材料为耳屏软骨(tragal cartilage)。在砧骨缺失的患者群体中，手术成功率达74.2%；若患者镫骨缺失，手术成功率降至63.3%；若锤骨缺失，则85%的患者术后气骨导差≤20 dB。 研究结论 本研究中听骨链成形术取得了良好的听力学预后效果，该结果与其他医疗中心的同类研究报道基本相当。听骨的局部状态会显著影响术后疗效，其中尤以镫骨的存在与否对预后的影响最为突出。本研究同时证实，本次分析的两项评估指标可有效辅助预测听骨链成形术的手术成功可能性。