Development of a laser holography otoscope for diagnosis in the clinic

传导性听力损失通常与中耳疾病有关，是耳科手术最常见的原因。导电性丧失的发病机制包括急性中耳感染、慢性中耳感染、听骨链疾病（如耳硬化）、头部或耳部创伤以及内耳病理性第三窗口。传导性听力损失的手术治疗从简单的（鼓膜切开术和鼓室造瘘管插入）到复杂的（乳突切除术后中耳全重建）。耳科检查比较容易诊断急性感染和中耳积液，而鼓膜完好、中耳干燥的传导性损失的原因则不容易确定。此外，虽然鼓室成形术是慢性中耳疾病后的常见手术（每年在我们机构进行的此类手术超过500例），但这些手术后的听力结果变化很大。我们的基本假设是：(a)完整TM的传导性听力障碍的术前诊断和(b)听骨和TM重建手术失败的原因评估可以通过测量TM的声致运动来改进。我们对动物和颞骨中声音诱发TM运动的全视场全息测量分析支持了这一假设。这些测量数据是用一个原型全息系统收集的，该系统目前被用作MEEI的研究工具。该提案将有助于将现有的全息平台转化为紧凑的全息设备，用于测量活体患者可见TM的运动。新设备将被设计用于临床环境，它将通过伍斯特理工学院机械工程系的光学测量专家和马萨诸塞州眼耳医院的听觉科学家和临床医生之间的合作开发。

Conductive hearing loss, usually associated with middle-ear disorders, is the most common reason for otologic surgery. The pathogenesis of conductive loss includes, among others, acute middle-ear infection, chronic middle-ear infection, diseases of the ossicular chain (e.g. otosclerosis), trauma to the head or ear and pathologic third-windows of the inner ear. Surgical treatments for conductive hearing loss range from the simple (myringotomy and tympanostomy tube insertion) to the complex (total reconstruction of the middle ear after mastoidectomy). While acute infections and middle-ear effusion are relatively easily diagnosed on otologic examination, the cause of conductive loss with an intact tympanic membrane (TM) and dry middle ear is not easily determined. Furthermore, while tympanoplasty is a common procedure after chronic middle-ear disease (with over 500 such procedures performed in our institution each year), the hearing outcome after these procedures is highly variable. Our fundamental hypothesis is that both (a) the pre-surgical diagnosis of conductive-hearing disorders with intact TM and (b) the evaluation of causes of surgical failure in ossicular and TM reconstructions can be improved by measurements of the sound-induced motions of the TM. This hypothesis is supported by our analyses of full-field-of-view holographic measurements of sound-induced TM motions in animals and temporal bones. These measurements were gathered using a prototype holographic system that is currently used as a research tool at the MEEI. This proposal will aid in the translation of the available holographic platform into a compact holographic device for measurements of the motions of the visible TM in live patients. The new device will be designed for use in a clinical environment and it will be developed via a cooperative venture between the optical measurement experts within the Mechanical Engineering Department of the Worcester Polytechnic Institute and auditory scientists and clinicians at the Massachusetts Eye and Ear Infirmary.