Falk B
J Otolaryngol. 1981 Aug;10(4):299-305.
In routine clinical tympanometry the finding of negative middle ear pressure is not uncommon. The traditional explanation of the negative pressure is that passive gas resorption takes place when the Eustachian tube is blocked. However, recent investigations in patients with middle ear disease have shown that a high negative intratympanic pressure can be actively induced by sniffing. In the present study 100 subjects with healthy ears were investigated by tympanometry in order to evaluate their ability to evacuate the middle ear by sniffing. Fourteen per cent were able to evacuate the middle ear to stable negative pressures ranging from -1.0 to -3.5 kPa, mean value -1.9 kPa (1 kPa corresponds approximately to 100 mm water). The present findings indicate that a sniff-induced negative pressure is not pathological per se. A temporary negative middle ear pressure induced by sniffing can explain the presence of a type C tympanogram in patients with healthy ears. This findings also emphasizes the difficulty in determining the borderline between normal and pathological tympanograms.
在常规临床鼓室导抗测量中，发现中耳负压并不罕见。对这种负压的传统解释是，当咽鼓管堵塞时会发生被动性气体吸收。然而，最近对中耳疾病患者的研究表明，通过吸气可主动诱发较高的鼓室内负压。在本研究中，对100名听力正常的受试者进行了鼓室导抗测量，以评估他们通过吸气排空中耳的能力。14%的受试者能够将中耳排空至稳定的负压，范围为-1.0至-3.5千帕，平均值为-1.9千帕（1千帕约相当于100毫米水柱）。目前的研究结果表明，吸气诱发的负压本身并非病理性的。吸气诱发的暂时性中耳负压可以解释听力正常的患者出现C型鼓室图的原因。这一研究结果也强调了确定正常鼓室图与病理性鼓室图界限的困难。
