Lewis Meagan P, Bradford Bell Elizabeth, Evans Adele K
Pediatric Audiology, Brenner Children's Hospital, Wake Forest University - Baptist Medical Center, Medical Center Boulevard, Winston-Salem, NC 27157, United States.
Int J Pediatr Otorhinolaryngol. 2011 Dec;75(12):1492-5. doi: 10.1016/j.ijporl.2011.06.008. Epub 2011 Sep 23.
For children with Down syndrome, the incidence of hearing loss may be as high as 78% [1], therefore the American Academy of Pediatrics recommends regular screening for the presence of hearing abnormalities. Tympanometry is used as an indication of middle ear pathology. In our experience, Down's patients' tympanograms do not always correlate with otoscopic findings. Down's patients have joint laxity, small ear canals, anterior tympanic membrane orientation and softer tissue composition, all factors thought to affect tympanogram results in infants. Because the use of the 1000 Hz tympanometry is widely recognized as standard procedure in the evaluation of infants aged 0-6 months, we propose it may have greater reliability in testing patients with Down syndrome.
Compare the results of visual inspection of the tympanic membrane by a Pediatric Otolaryngologist to the results of tympanometry at traditional probe tone (226 Hz) and at the infant probe tone (1000 Hz).
Institutional Review Board - approved prospective study of 26 subject-ears in patients with Down syndrome aged 6 months-18 years but recent stable middle ear/Eustachian tube function using physical examination and tympanometric probe tones at 226 Hz and 1000 Hz. Subject-ears were examined with record of "clear of effusion," showed the presence of "fluid," or were to be "excluded." Blinded to ear exam results, tympanometry was then completed with record of which Jerger classification tympanogram was found at each frequency.
Although the sensitivity of each test was 1, the specificity of the 1000 Hz tympanometry (100%) in this study was markedly improved compared to the specificity of the 226 Hz tympanometry (71%) (p=0.016).
This pilot study demonstrated evidence that tympanometry in children with Down syndrome may be more reliable at 1000 Hz than at 226 Hz in detecting the presence of middle ear effusion beyond infancy. Use of the 1000 Hz probe tone yielded fewer false positives for disease (type B tympanograms in the setting of absent middle ear disease). Further studies of a larger patient population are needed to corroborate these results.
对于唐氏综合征患儿，听力损失发生率可能高达78%[1]，因此美国儿科学会建议定期筛查听力异常情况。鼓室导抗图检查用于评估中耳病变。根据我们的经验，唐氏综合征患者的鼓室导抗图结果并不总是与耳镜检查结果相符。唐氏综合征患者存在关节松弛、耳道狭小、鼓膜前倾以及组织成分较软等情况，所有这些因素都被认为会影响婴儿的鼓室导抗图检查结果。由于使用1000Hz鼓室导抗图检查在评估0至6个月婴儿时被广泛认可为标准程序，我们认为其在检测唐氏综合征患者时可能具有更高的可靠性。
比较儿科耳鼻喉科医生对鼓膜的肉眼检查结果与传统探测音（226Hz）及婴儿探测音（1000Hz）鼓室导抗图检查结果。
经机构审查委员会批准，对26例6个月至18岁唐氏综合征患者的受试耳进行前瞻性研究，这些患者近期中耳/咽鼓管功能稳定，采用体格检查以及226Hz和1000Hz鼓室导抗探测音检查。受试耳经检查记录为“无积液”、“有积液”或“排除”。在不知耳部检查结果的情况下，然后进行鼓室导抗图检查，并记录每个频率下发现的杰格分类鼓室导抗图类型。
尽管每项检查的敏感度均为1，但本研究中1000Hz鼓室导抗图检查的特异度（100%）与226Hz鼓室导抗图检查的特异度（71%）相比有显著提高（p = 0.016）。
这项初步研究表明，在检测婴儿期以外的中耳积液方面，唐氏综合征患儿1000Hz鼓室导抗图检查可能比226Hz鼓室导抗图检查更可靠。使用1000Hz探测音对疾病产生的假阳性结果更少（在无中耳疾病情况下出现B型鼓室导抗图）。需要对更多患者群体进行进一步研究以证实这些结果。
