Andrews J C, Böhmer A, Hoffman L, Strelioff D
Division of Head and Neck Surgery, University of California Los Angeles Medical Center, Los Angeles 90095-1624, USA.
Am J Otol. 2000 Sep;21(5):652-6.
Experimental endolymphatic hydrops leads to an endolymph-perilymph pressure imbalance that is responsible for the loss of auditory sensitivity in the ear.
This study investigates whether intralabyrinthine pressure is a factor in the auditory dysfunction of experimental endolymphatic hydrops.
Auditory function was investigated in 10 guinea pigs 90 to 120 days after endolymphatic sac ablation by measuring compound action potentials in response to acoustic stimuli including alternating clicks and tone bursts of 0.5, 1, 2, 4, and 8 kHz. After auditory thresholds to the various stimuli were established, endolymphatic and perilymphatic pressures were measured with a no-flow micropressure measuring system. The cause of the hearing loss in Meniere's disease, especially in the early phases of this condition, remains an enigma. Histologic temporal bone preparations show a disproportion in the volume of endolymph to perilymph with an expanded and distorted membranous labyrinth. Speculation as to whether an endolymph-perilymph fluid pressure imbalance is responsible for these morphologic changes were raised by Hallpike and Cairns (1) in their initial report of the histopathology of Meniere's disease. Further speculation has questioned whether this pressure imbalance may be responsible for the symptoms and physical finding of this condition, including hearing loss. The ability to produce experimental endolymphatic hydrops in the guinea pig secondary to surgical occlusion of the endolymphatic sac and duct has been useful in studying various aspects of Meniere's disease (2). Investigators have been able to demonstrate auditory threshold shifts with hydrops. Elevated endolymph-perilymph pressure gradients have also been demonstrated (3). This
Increased auditory thresholds were noted in the hydrops ears at all tested parameters (p < 0.03). A relative increase in endolymph over perilymph pressure was found in hydrops ears as previously reported. The increase in endolymph-perilymph pressure of hydrops could not be correlated directly to the elevated auditory threshold shift.
Endolymphatic hydrops is a complex pathologic state with multiple inner ear alterations including abnormal intralabyrinthine pressure. Factors other than or in addition to pressure contribute to the auditory threshold shift of hydrops.
实验性内淋巴积水导致内淋巴-外淋巴压力失衡，这是耳部听觉敏感性丧失的原因。
本研究调查迷路内压力是否是实验性内淋巴积水听觉功能障碍的一个因素。
在内淋巴囊切除术后90至120天，对10只豚鼠进行听觉功能研究，通过测量对包括交替滴答声和0.5、1、2、4和8千赫兹短纯音在内的声刺激的复合动作电位来进行。在确定了对各种刺激的听觉阈值后，使用无流量微压力测量系统测量内淋巴和外淋巴压力。梅尼埃病听力损失的原因，尤其是在这种疾病的早期阶段，仍然是一个谜。颞骨组织学标本显示内淋巴与外淋巴的体积不成比例，膜迷路扩张和扭曲。Hallpike和Cairns（1）在其关于梅尼埃病组织病理学的初步报告中提出了关于内淋巴-外淋巴液压力失衡是否是这些形态学变化原因的推测。进一步的推测质疑这种压力失衡是否可能是这种疾病的症状和体征的原因，包括听力损失。通过手术阻塞内淋巴囊和导管在豚鼠中产生实验性内淋巴积水的能力，在研究梅尼埃病的各个方面一直很有用（2）。研究人员已经能够证明积水时听觉阈值的变化。也已经证明了内淋巴-外淋巴压力梯度升高（3）。
在所有测试参数下，积水耳的听觉阈值均升高（p < 0.03）。如先前报道，在积水耳中发现内淋巴相对于外淋巴压力相对增加。积水时内淋巴-外淋巴压力的增加与听觉阈值升高的变化没有直接相关性。
内淋巴积水是一种复杂的病理状态，伴有内耳的多种改变，包括迷路内压力异常。除压力之外或压力之外的其他因素导致积水时听觉阈值的变化。
