Manzari Leonardo, Modugno Giovanni Carlo
Department of Experimental Medicine and Pathology, La Sapienza University, Rome, Italy.
Med Sci Monit. 2008 Oct;14(10):CR505-10.
The aim was to explore vestibular responses to bone vibration-induced nystagmus (BVIN) during bed-side examination in patients with otosclerosis and conductive hearing loss. It is assumed that vibration of the mastoid (at 100 Hz) stimulates all vestibular end organs (semicircular canals and otolith structures). Previous studies described oculomotor responses to vestibular activation by vibratory stimulus. Stimulation of individual semicircular canals produces eye movement in the plane of the stimulated canal. Vibratory stimulation of otolith structures (utricular macula) produces changes in ocular torsional position. Otosclerosis is responsible for conductive hearing loss and symptoms such as dizziness and vertigo. Diagnosis is usually by a combination of family medical history, conductive hearing loss pattern, absence of air-VEMP, and CT scan of the temporal bone.
MATERIAL/METHODS: Eye movements of patients diagnosed with otosclerosis and conductive hearing loss were recorded in complete darkness. These oculomotor responses to long-lasting unilateral vibratory stimulation applied to the mastoid surface were evaluated and the patterns of vertical, torsional, and horizontal eye velocity and eye position were measured by three-dimensional computerized infrared video oculography.
Mastoid vibration evoked responses in all cases, mostly demonstrating excitation of the affected side. In all cases, three-dimensional infrared video oculography showed mostly horizontal nystagmus directed with the slow phase to the healthy side.
Three-dimensional analysis of BVIN in patients with otosclerosis and conductive hearing loss may be appropriate in evaluating the vestibular function and altered immittance related with this clinical entity. This promises to be an interesting new field of research.
目的是探讨耳硬化症和传导性听力损失患者床边检查期间对骨振动诱发眼震（BVIN）的前庭反应。假定乳突振动（100Hz）刺激所有前庭终器（半规管和耳石结构）。既往研究描述了振动刺激引起的前庭激活的眼动反应。刺激单个半规管会在受刺激半规管平面产生眼球运动。耳石结构（椭圆囊斑）的振动刺激会导致眼球扭转位置发生变化。耳硬化症可导致传导性听力损失以及头晕和眩晕等症状。诊断通常结合家族病史、传导性听力损失模式、无气导前庭诱发肌源性电位以及颞骨CT扫描。
材料/方法：在完全黑暗环境中记录诊断为耳硬化症和传导性听力损失患者的眼球运动。评估这些对乳突表面施加的长时间单侧振动刺激的眼动反应，并通过三维计算机化红外视频眼动图测量垂直、扭转和水平眼速度及眼位模式。
所有病例中乳突振动均诱发反应，大多表现为患侧兴奋。所有病例中，三维红外视频眼动图大多显示慢相指向健侧的水平眼震。
对耳硬化症和传导性听力损失患者的BVIN进行三维分析可能适用于评估与该临床实体相关的前庭功能和改变的声导抗。这有望成为一个有趣的新研究领域。
