Cole Lynette K, Rajala-Schultz Päivi J, Lorch Gwendolen
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, 1900 Coffey Rd, Columbus, OH, 43210, USA.
Department of Production Animal Medicine, Faculty of Veterinary Medicine, University of Helsinki, Paroninkuja 20, 04920, Saarentaus, Finland.
Vet Dermatol. 2018 Apr 17. doi: 10.1111/vde.12542.
Hearing loss (HL) is classified as conductive when sound transmission is compromised in the ear canal or middle ear, or sensorineural when there is an abnormality of the receptor cells of the cochlea or auditory pathway. Hearing in dogs is evaluated using the brainstem auditory evoked response (BAER) test.
HYPOTHESIS/OBJECTIVES: Our objective was to characterize BAER findings pre- and post-ear flushing in four dogs with acute HL following application of an ointment-based otic medication containing betamethasone, clotrimazole and gentamicin in a mineral oil-based system containing a plasticized hydrocarbon gel.
Dogs, ranging from 9 to 11 years old, that had been treated with the otic medication for one to three weeks prior to hearing loss and on otoscopic examination had evidence of medication in the horizontal ear canals.
Dogs were anaesthetized for an ear flush to remove the medication from the ear canals. Hearing was assessed using BAER testing, measurements were initiated with 116 decibel peak equivalent sound pressure level (dBpeSPL) click. Estimated threshold was defined as the lowest intensity in dB in which wave V was still present.
Post-ear flush the estimated threshold improved in both ears of all dogs (mean 22.3 dB; range 13-41 dB), confirming conductive HL due to the otic medication. All owners noted an improvement in their dog's hearing post-ear flush, validating the BAER findings.
These results emphasize the importance of an ear flush to remove otic medications in dogs that experience acute HL, to determine if the HL is conductive, and if so, to restore hearing.
当外耳道或中耳的声音传导受损时，听力损失（HL）被分类为传导性听力损失；当耳蜗或听觉通路的受体细胞出现异常时，则被分类为感音神经性听力损失。犬类的听力通过脑干听觉诱发电位（BAER）测试进行评估。
假设/目的：我们的目的是对4只急性HL犬在使用含有倍他米松、克霉唑和庆大霉素的油膏状耳用药物后进行耳冲洗前后的BAER结果进行特征描述，该药物以含有增塑烃凝胶的矿物油为基质。
年龄在9至11岁之间的犬只，在听力损失前已使用该耳用药物治疗1至3周，耳镜检查显示水平耳道内有药物残留。
对犬只进行麻醉以冲洗耳朵，清除耳道内的药物。使用BAER测试评估听力，测量从116分贝峰值等效声压级（dBpeSPL）的点击声开始。估计阈值定义为波V仍存在时的最低强度分贝数。
耳冲洗后，所有犬只双耳的估计阈值均有所改善（平均22.3分贝；范围13 - 41分贝），证实了耳用药物导致的传导性HL。所有犬主均注意到其犬只在耳冲洗后听力有所改善，验证了BAER结果。
这些结果强调了对经历急性HL的犬只进行耳冲洗以清除耳用药物的重要性，以此确定HL是否为传导性，如果是，则恢复听力。
