Department of Mechanical Engineering, Faculty of Engineering, Graduate Faculty of Interdisciplinary Research, University of Yamanashi, Yamanashi, Japan.
Department of Mechanical and Intelligent Systems Engineering, Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan.
Sci Rep. 2024 Sep 3;14(1):20468. doi: 10.1038/s41598-024-71474-4.
Ossicular fixation disturbs the mobility of the ossicular chain and causes conductive hearing loss. To diagnose the lesion area, otologists typically assess ossicular mobility through intraoperative palpation. Quantification of ossicular mobility and evidence-based diagnostic criteria are necessary for accurate assessment of each pathology, because diagnosis via palpation can rely on the surgeons' experiences and skills. In this study, ossicular mobilities were simulated in 92 pathological cases of ossicular fixation as compliances using a finite-element (FE) model of the human middle ear. The validity of the ossicular mobilities obtained from the FE model was verified by comparison with measurements of ossicular mobilities in cadavers using our newly developed intraoperative ossicular mobility measurement system. The fixation-induced changes in hearing were validated by comparison with changes in the stapedial velocities obtained from the FE model with measurements reported in patients and in temporal bones. The 92 cases were classified into four groups by conducting a cluster analysis based on the simulated ossicular compliances. Most importantly, the cases of combined fixation of the malleus and/or the incus with otosclerosis were classified into two different surgical procedure groups by degree of fixation, i.e., malleo-stapedotomy and stapedotomy. These results suggest that pathological characteristics can be detected using quantitatively measured ossicular compliances followed by cluster analysis, and therefore, an effective diagnosis of ossicular fixation is achievable.
听骨固定会干扰听骨链的活动，导致传导性听力损失。为了诊断病变部位，耳科医生通常通过术中触诊来评估听骨的活动度。为了准确评估每种病理，需要对听骨活动度进行量化，并制定基于证据的诊断标准，因为触诊诊断可能依赖于外科医生的经验和技能。在这项研究中，使用人体中耳的有限元（FE）模型模拟了 92 例听骨固定的病理情况，将听骨的活动度模拟为顺应性。通过与我们新开发的术中听骨活动度测量系统测量的尸体听骨活动度进行比较，验证了从 FE 模型获得的听骨活动度的有效性。通过与从 FE 模型获得的镫骨速度变化与患者和颞骨报告的测量值进行比较，验证了固定引起的听力变化。根据模拟的听骨顺应性，通过聚类分析将 92 例病例分为四组。最重要的是，根据镫骨和/或砧骨与耳硬化症的联合固定程度，将镫骨和砧骨联合固定的病例分为两种不同的手术程序组，即镫骨切开术和镫骨切除术。这些结果表明，可以通过定量测量听骨顺应性并进行聚类分析来检测病理特征，因此可以实现对听骨固定的有效诊断。
