Ohyama Y
Department of Otolaryngology, Nippon Medical School, Tokyo.
Nihon Jibiinkoka Gakkai Kaiho. 1999 Jan;102(1):50-7. doi: 10.3950/jibiinkoka.102.50.
The influence of dorsal neck proprioceptive inputs on vestibular compensation was investigated in 21 patients with unilateral vestibular dysfunction. Subjects neither had history of spontaneous nystagmus nor of disequilibrium, indicating that they were in a good compensated stage. However, marked nystagmus was induced by applying vibratory stimulation to the dorsal neck of the patients, using a vibrator with a frequency of 110 Hz. The nystagmus was three-dimensional as analyzed by applying computerized eye movement analysis system. Twelve of 21 patients (57%) demonstrated three components of eye movement. All subjects showed a horizontal component directed towards the contralateral side of the vestibular lesion. Vertical and torsional components of the nystagmus were exhibited by 18 and 14 subjects, respectively. The average percentages of slow phase velocity of the horizontal, vertical and torsional components were 57%, 23% and 20%, respectively. No tendency towards any of the three components was observed. Furthermore, in order to investigate the relation between dorsal neck proprioceptive inputs and vestibular outputs, especially semicircular canal outputs, the author compared the direction of the nystagmus with the orientation of the semicircular canals. Normalized average velocity vectors of the nystagmus were calculated. In most subjects, the velocity vectors of the nystagmus were related to the horizontal semicircular canal. These results suggest that by controlling the neck proprioceptive inputs, neck vibration can cause discompensation in vestibularly well-compensated subjects with unilateral dysfunction secondary to vestibular lesion, and that neck proprioceptive inputs have a great influence on the horizontal vestibulo-ocular reflex pathways. However, in a few subjects the average vectors of the nystagmus were related to the vertical semicircular canals. This suggests that the proprioceptive inputs may also be related to the vertical vestibulo-ocular reflex pathways.
在21例单侧前庭功能障碍患者中，研究了颈背部本体感觉输入对前庭代偿的影响。受试者既无自发性眼球震颤病史，也无平衡失调病史，表明他们处于良好的代偿阶段。然而，使用频率为110Hz的振动器对患者颈背部施加振动刺激时，诱发了明显的眼球震颤。应用计算机化眼动分析系统分析，该眼球震颤为三维的。21例患者中有12例（57%）表现出眼动的三个成分。所有受试者均表现出指向前庭病变对侧的水平成分。分别有18例和14例受试者表现出眼球震颤的垂直和扭转成分。水平、垂直和扭转成分慢相速度的平均百分比分别为57%、23%和20%。未观察到对这三个成分中的任何一个有偏好倾向。此外，为了研究颈背部本体感觉输入与前庭输出，特别是半规管输出之间的关系，作者将眼球震颤的方向与半规管的方向进行了比较。计算了眼球震颤的归一化平均速度矢量。在大多数受试者中，眼球震颤的速度矢量与水平半规管有关。这些结果表明，通过控制颈部本体感觉输入，颈部振动可使继发于前庭病变的单侧功能障碍且前庭代偿良好的受试者出现失代偿，并且颈部本体感觉输入对水平前庭眼反射通路有很大影响。然而，在少数受试者中，眼球震颤的平均矢量与垂直半规管有关。这表明本体感觉输入也可能与垂直前庭眼反射通路有关。
