Hong S H, Cho Y S, Chung W H, Koh S J, Seo I S, Woo H C
Department of Otorhinolaryngology--Head and Neck Surgery, Sungkyunkwan University School of Medicine, Samsung Medical Center, 50 Ilwon-Dong, Kangnam-Gu, Seoul, South Korea.
Int J Pediatr Otorhinolaryngol. 2001 Apr 27;58(2):147-52. doi: 10.1016/s0165-5876(01)00420-7.
As otitis media with effusion is common in children, the effects of a ventilation tube should be taken into account in the prescription of hearing aids for children. In ears with a ventilation tube, the external auditory canal communicates directly with the middle ear space, and so the impedance of the middle ear may change. Consequently, this will affect external-ear resonance. The aim of this study is to observe the effects of the tympanic membrane perforations caused by the ventilation tube on external-ear resonance. We selected 30 ears with otitis media with effusion to measure external-ear resonance before and after ventilation tube insertion. We compared the external-ear resonance of a control group with that of the otitis media with the effusion group and two types of ventilation-tube groups, respectively. In the subjects who have otitis media with effusion, the average gain of the peak resonance was larger than that in the control group. After ventilation-tube insertion, the amplitude of the gain decreased to the same level as the control group, but a characteristic negative gain appeared around 1000 Hz in about half of all cases. This negative gain was observed more frequently in the ventilation tube with a larger diameter. The raised peak resonance gain in the otitis media with effusion group decreased to a level roughly the same as that of the control group after ventilation-tube insertion. Provision of an additional gain in the low frequencies around 1000 Hz should be considered for patients with a ventilation tube when prescribing hearing aids.
由于分泌性中耳炎在儿童中很常见，因此在为儿童开助听器处方时应考虑通气管的影响。在有通气管的耳朵中，外耳道直接与中耳腔相通，因此中耳的阻抗可能会发生变化。因此，这将影响外耳共振。本研究的目的是观察通气管引起的鼓膜穿孔对外耳共振的影响。我们选择了30例分泌性中耳炎患者，在插入通气管前后测量外耳共振。我们分别将对照组的外耳共振与分泌性中耳炎组和两种通气管组的外耳共振进行了比较。在分泌性中耳炎患者中，峰值共振的平均增益大于对照组。插入通气管后，增益幅度降至与对照组相同的水平，但在大约一半的病例中，在1000 Hz左右出现了特征性的负增益。在直径较大的通气管中更频繁地观察到这种负增益。分泌性中耳炎组升高的峰值共振增益在插入通气管后降至与对照组大致相同的水平。在为有通气管的患者开助听器处方时，应考虑在1000 Hz左右的低频提供额外增益。
