Assessment of middle ear structure and function with optical coherence tomography

Abstract

Background

Current clinical tests for middle ear (ME) injuries and related conductive hearing loss (CHL) are lengthy and costly, lacking the ability to noninvasively evaluate both structure and function in real time. Optical coherence tomography (OCT) provides both, but its application to the audiological clinic is currently limited.

Objective

Adapt and use a commercial Spectral-Domain OCT (SD-OCT) to evaluate anatomy and sound-evoked vibrations of the tympanic membrane (TM) and ossicles in the human ME.

Materials and Methods

SD-OCT was used to capture high-resolution three-dimensional (3D) ME images and measure sound-induced vibrations of the TM and ossicles in fresh human temporal bones.

Results

The 3D images provided thickness maps of the TM. The system was, with some software adaptations, also capable of phase-sensitive vibrometry. Measurements revealed several modes of TM vibration that became more complex with frequency. Vibrations were also measured from the incus, through the TM. This quantified ME sound transmission, which is the essential measure to assess CHL.

Conclusion and Significance

We adapted a commercial SD-OCT to visualize the anatomy and function of the human ME. OCT has the potential to revolutionize point-of-care assessment of ME disruptions that lead to CHL which are otherwise indistinguishable via otoscopy.

Chinese Abstract

背景：目前针对中耳 (ME) 损伤和相关的传导性听力损失 (CHL) 的临床检测耗时长且昂贵, 缺乏非侵入性地评估实时结构和功能的能力。 光学相干断层扫描 (OCT) 提供结构和功能, 但它在听力诊所的应用目前还是有限的。

目的：调整并使用商业光谱域 OCT (SD-OCT) 来评估人类中耳解剖学和鼓膜 (TM) 和小骨的声音诱发振动。

材料和方法：SD-OCT 用于获取高分辨率三维 (3D) 中耳图像并测量新鲜人颞骨中鼓膜 和小骨的声音诱发振动。

结果：三维图像提供了鼓膜的厚度图。通过一些软件调整, 该系统也能够进行相敏振动测量。 测量揭示了鼓膜振动的几种模式, 且随着频率增高变得更加复杂。 还通过鼓膜测量了砧骨振动。 这样做, 量化了中耳声音传输, 后者是评估传导性听力损失的基本措施。

结论和意义：我们采用商业 SD-OCT 来可视化中耳的解剖结构和功能。 OCT 有可能改革即时评估导致传导性听力损失的中耳疾患。而通过耳镜无法鉴别传导性听力损失。

Keywords:

• Optical coherence tomography
• middle ear
• tympanic membrane
• ossicles
• middle ear sound transmission
• conductive hearing loss

Acknowledgments

This study was supported by the Rehabilitation Research and Development Service Merit Review Award 101RX002296 (WD), and the Department of Otolaryngology Head & Neck Surgery, at Loma Linda University Health. These contents do not represent the views of the U.S. Department of Veterans Affairs or the United States Government. There is no conflict of interest for all authors.

Author contributions

TTKJ, YL, and WD designed the experiments. All authors were involved in performing the experiments. SWFM and LMA analyzed data. SWFM developed software for data acquisition and analysis. SWFM and WD wrote the paper.

Disclosure statement

No potential conflict of interest was reported by the author(s).