Dumas G, Schmerber S, Lavieille J P
Clinique ORL, Centre Hospitalier Albert Michalon, 38043, Grenoble Cedex, France.
Ann Otolaryngol Chir Cervicofac. 2003 Nov;120(5):286-95.
The aim of the present study was to examine the characteristics of vibratory nystagmus (VN), optimise the topography and the frequency of the stimulus, determine the origin of the VN and analyze its clinical implications.
Fifty-two severe unilateral vestibular lesions (SUVL) (post-surgical vestibular areflexy) were studied. The vibratory nystagmus was measured by 2D and 3D videonystagmography (Synapsis, France). The stimulus was applied with a 3S vibrator at the vertex, both mastoïds, and posterior cervical muscles, at frequencies ranging from 20 to 150 Hz. For topographic optimization, stimulation was given with S vibrator (Synapsis, France) at 100 Hz. The interferences between the vibratory test (VT) and the caloric test (CT) were studied on the normal ear (in 11 subjects). The same study was carried out with the optokinetic test.
The VT revealed a defective nystagmus at all frequencies of stimulation. Optimal response was obtained in a band frequency of 80-120 Hz. Stimulations at 100 Hz showed optimal responses for mastoid topography (responses in 96% of the cases). Stimulation at the posterior cervical muscles and at the vertex indicated respectively a response in 90% and 60% of the cases. The efficiency of the mastoid stimulation was not correlated with the side of stimulation (p=0.9). The interference between the VT and caloric test (CT) with cold water (30 degrees C and 20 degrees C) exhibited the inversion of the caloric nystagmus during the vibrator stimulation. The resulting nystagmus was respectively an algebraic subtraction or addition between the pre-existing caloric nystagmus and the value of the vibratory nystagmus obtained before the caloric test. Adaptation of the VN was moderate. The interference between the VT and the optokinetic test resulted in a subtraction or addition effect, according to the side of the lesion and the direction of the optokinetic stimulus.
The VT is an efficient stimulation in mastoid topography. The vestibular contribution is bilateral by bony conduction of the vibration, it explores frequencies ranging from 30 to 120 Hz, with a maximum of response at 100 Hz. The VT interacts with the caloric test and the optokinetic test. The stimulation is very strong, and is able to inverse the caloric nystagmus at cold water stimulation (20 degrees C) In labyrinthine-defective subjects, the VN is always defective at all frequencies, whatever the topographic location of the stimulus, and the position of the head.
本研究旨在探讨振动性眼震（VN）的特征，优化刺激的地形图和频率，确定VN的起源并分析其临床意义。
研究了52例严重单侧前庭病变（SUVL）（术后前庭无反应）患者。通过二维和三维视频眼震电图（法国Synapsis公司）测量振动性眼震。使用3S振动器在头顶、双侧乳突和颈后肌肉处施加刺激，频率范围为20至150Hz。为了进行地形图优化，使用法国Synapsis公司的S振动器以100Hz进行刺激。在正常耳（11名受试者）上研究了振动试验（VT）和冷热试验（CT）之间的干扰。对视动试验也进行了同样的研究。
VT显示在所有刺激频率下眼震均有异常。在80 - 120Hz的频段内获得了最佳反应。100Hz刺激时乳突地形图显示出最佳反应（96%的病例有反应）。颈后肌肉和头顶刺激分别在90%和60%的病例中有反应。乳突刺激的效果与刺激侧无关（p = 0.9）。VT与冷水（30℃和20℃）冷热试验之间的干扰表现为在振动器刺激期间冷热性眼震的反转。产生的眼震分别是预先存在的冷热性眼震与冷热试验前获得的振动性眼震值之间的代数相减或相加。VN的适应性为中等。VT与视动试验之间的干扰根据病变侧和视动刺激的方向产生相减或相加效应。
VT在乳突地形图上是一种有效的刺激。前庭的贡献通过振动的骨传导是双侧性的，它探索的频率范围为30至120Hz，在100Hz时反应最大。VT与冷热试验和视动试验相互作用。刺激非常强烈，并能够在冷水刺激（20℃）时反转冷热性眼震。在迷路功能障碍的受试者中，无论刺激的地形图位置和头部位置如何，VN在所有频率下始终异常。
