Urban P P, Marczynski U, Hopf H C
University Department of Neurology, Mainz, Germany.
Brain. 1993 Jun;116 ( Pt 3):727-38. doi: 10.1093/brain/116.3.727.
The oculo-auricular phenomenon consists of bilateral coactivation of external ear muscles during lateral gaze. The electromyogram of the transverse auricular muscle was recorded in 25 healthy volunteers and 1186 patients. In normal subjects bilateral coactivation was observed with lateral gaze (96%), convergence (61%), active and intended head rotation (100%) and passive head rotation (50%). Uni- and bilateral labyrinthine excitation (60 and 80%) and proprioceptive input from the neck muscles (38%) are also effective. In patients with brainstem disease abnormal transverse auricular muscle coactivation is characterized by absence of activity in one or both ear muscles during lateral gaze in either or both directions. The most frequent abnormality was absence of transverse auricular muscle activity homolateral to right or left gaze (type Ia pattern). It was related to homolateral impairment of the blink reflex R1-response (90%) and the caloric response (90%), and to contralateral masseter reflex abnormality (70%). Electrophysiological data, clinical signs and imaging findings indicate that the type Ia pattern is caused by homolateral pontine or contralateral midbrain lesions. It is suggested that the supranuclear organization of the oculo-auricular phenomenon is based on descending tracts crossing at a mid-pontine level.
眼耳现象是指在侧方凝视时双侧外耳道肌肉共同激活。在25名健康志愿者和1186名患者中记录了耳横肌的肌电图。在正常受试者中，侧方凝视（96%）、集合（61%）、主动和有意的头部转动（100%）以及被动头部转动（50%）时可观察到双侧共同激活。单侧和双侧迷路兴奋（分别为60%和80%）以及来自颈部肌肉的本体感觉输入（38%）也有效。在脑干疾病患者中，耳横肌异常共同激活的特征是在任一或两个方向的侧方凝视时，一侧或双侧耳部肌肉无活动。最常见的异常是与右侧或左侧凝视同侧的耳横肌活动缺失（Ia型模式）。它与同侧眨眼反射R1反应（90%）和冷热反应（90%）受损以及对侧咬肌反射异常（70%）有关。电生理数据、临床体征和影像学检查结果表明，Ia型模式是由同侧脑桥或对侧中脑病变引起的。有人提出，眼耳现象的核上组织是基于在脑桥中部水平交叉的下行束。
