Keefe Douglas H, Archer Kelly L, Schmid Kendra K, Fitzpatrick Denis F, Feeney M Patrick, Hunter Lisa L
Boys Town National Research Hospital, Omaha, NE.
University of Nebraska Lincoln, Lincoln, NE.
J Am Acad Audiol. 2017 Oct;28(9):838-860. doi: 10.3766/jaaa.16172.
Otosclerosis is a progressive middle-ear disease that affects conductive transmission through the middle ear. Ear-canal acoustic tests may be useful in the diagnosis of conductive disorders. This study addressed the degree to which results from a battery of ear-canal tests, which include wideband reflectance, acoustic stapedius muscle reflex threshold (ASRT), and transient evoked otoacoustic emissions (TEOAEs), were effective in quantifying a risk of otosclerosis and in evaluating middle-ear function in ears after surgical intervention for otosclerosis.
To evaluate the ability of the test battery to classify ears as normal or otosclerotic, measure the accuracy of reflectance in classifying ears as normal or otosclerotic, and evaluate the similarity of responses in normal ears compared with ears after surgical intervention for otosclerosis.
A quasi-experimental cross-sectional study incorporating case control was used. Three groups were studied: one diagnosed with otosclerosis before corrective surgery, a group that received corrective surgery for otosclerosis, and a control group.
The test groups included 23 ears (13 right and 10 left) with normal hearing from 16 participants (4 male and 12 female), 12 ears (7 right and 5 left) diagnosed with otosclerosis from 9 participants (3 male and 6 female), and 13 ears (4 right and 9 left) after surgical intervention from 10 participants (2 male and 8 female).
Participants received audiometric evaluations and clinical immittance testing. Experimental tests performed included ASRT tests with wideband reference signal (0.25-8 kHz), reflectance tests (0.25-8 kHz), which were parameterized by absorbance and group delay at ambient pressure and at swept tympanometric pressures, and TEOAE tests using chirp stimuli (1-8 kHz). ASRTs were measured in ipsilateral and contralateral conditions using tonal and broadband noise activators. Experimental ASRT tests were based on the difference in wideband-absorbed sound power before and after presenting the activator. Diagnostic accuracy to classify ears as otosclerotic or normal was quantified by the area under the receiver operating characteristic curve (AUC) for univariate and multivariate reflectance tests. The multivariate predictor used a small number of input reflectance variables, each having a large AUC, in a principal components analysis to create independent variables and followed by a logistic regression procedure to classify the test ears.
Relative to the results in normal ears, diagnosed otosclerosis ears more frequently showed absent TEOAEs and ASRTs, reduced ambient absorbance at 4 kHz, and a different pattern of tympanometric absorbance and group delay (absorbance increased at 2.8 kHz at the positive-pressure tail and decreased at 0.7-1 kHz at the peak pressure, whereas group delay decreased at positive and negative-pressure tails from 0.35-0.7 kHz, and at 2.8-4 kHz at positive-pressure tail). Using a multivariate predictor with three reflectance variables, tympanometric reflectance (AUC = 0.95) was more accurate than ambient reflectance (AUC = 0.88) in classifying ears as normal or otosclerotic.
Reflectance provides a middle-ear test that is sensitive to classifying ears as otosclerotic or normal, which may be useful in clinical applications.
耳硬化症是一种进行性中耳疾病，会影响通过中耳的传导性传输。耳道声学测试可能有助于传导性障碍的诊断。本研究探讨了一系列耳道测试（包括宽带反射率、镫骨肌声反射阈值[ASRT]和瞬态诱发耳声发射[TEOAEs]）在量化耳硬化症风险以及评估耳硬化症手术干预后耳朵的中耳功能方面的有效程度。
评估该测试组合将耳朵分类为正常或耳硬化症的能力，测量反射率在将耳朵分类为正常或耳硬化症方面的准确性，并评估正常耳朵与耳硬化症手术干预后耳朵的反应相似性。
采用了纳入病例对照的准实验性横断面研究。研究了三组：一组在矫正手术前被诊断为耳硬化症，一组接受了耳硬化症矫正手术，以及一个对照组。
测试组包括来自16名参与者（4名男性和12名女性）的23只听力正常的耳朵（13只右耳和10只左耳），来自9名参与者（3名男性和6名女性）的12只被诊断为耳硬化症的耳朵（7只右耳和5只左耳），以及来自10名参与者（2名男性和8名女性）的13只手术干预后的耳朵（4只右耳和9只左耳）。
参与者接受了听力评估和临床声导抗测试。进行的实验测试包括使用宽带参考信号（0.25 - 8 kHz）的ASRT测试、反射率测试（0.25 - 8 kHz），该测试通过在环境压力和扫频鼓室压力下的吸光度和群延迟进行参数化，以及使用啁啾刺激（1 - 8 kHz）的TEOAEs测试。使用纯音和宽带噪声刺激器在同侧和对侧条件下测量ASRT。实验性ASRT测试基于呈现刺激前后宽带吸收声功率的差异。通过单变量和多变量反射率测试的受试者工作特征曲线（AUC）下的面积来量化将耳朵分类为耳硬化症或正常的诊断准确性。多变量预测器在主成分分析中使用少量输入反射率变量，每个变量都有较大的AUC，以创建自变量，然后通过逻辑回归程序对测试耳朵进行分类。
相对于正常耳朵的结果，被诊断为耳硬化症的耳朵更频繁地表现出TEOAEs和ASRT缺失、4 kHz处环境吸光度降低以及鼓室吸光度和群延迟的不同模式（在正压尾部2.8 kHz处吸光度增加，在峰值压力0.7 - 1 kHz处吸光度降低，而群延迟在正负压力尾部从0.35 - 0.7 kHz以及在正压尾部2.8 - 4 kHz处降低）。使用具有三个反射率变量的多变量预测器，鼓室反射率（AUC = 0.95）在将耳朵分类为正常或耳硬化症方面比环境反射率（AUC = 0.88）更准确。
反射率提供了一种对将耳朵分类为耳硬化症或正常敏感的中耳测试，这在临床应用中可能有用。
