Testing of visual dependency on body sway and its application to balance rehabilitation

我们检查了15例视性眩晕综合征（VVS）。VVS被诊断为由特定视觉环境引发的头晕或不平衡。有9名男性和6名女性，平均年龄为43岁，范围为25至69岁。视觉环境包括看电视或电脑显示器（5例），在隧道中驾驶汽车（4例），在超市中行走（4例）和穿过人群（2例）。这些结果表明，特定的视觉环境中包含的光流诱导头晕VVS患者。因此，这表明，视觉依赖的身体摇摆增加VVS患者。然后，我们开发了一种新的设备来产生光流刺激，以评估身体摇摆的视觉依赖性。闭眼和睁眼时的摇摆路径之间的比率被称为Romberg比率，其显示了静态视觉对身体摇摆的依赖性。Romberg比率在健康志愿者和VVS患者中均增加。另一方面，有和没有光流刺激的摇摆路径之间的比率显示动态视觉依赖于身体摇摆。部分VVS患者的比值明显升高，而其他VVS患者和健康志愿者的比值无明显升高。这些结果表明，对身体摇摆的动态视觉依赖性增加是VVS发展的一个重要机制

We examined 15 patients with visual vertigo syndrome (VVS). VVS was diagnosed as having dizziness or imbalance triggered by the specific visual environments. There were 9 men and 6 women and their mean age was 43 years, range 25 to 69. The visual environments consisted of looking at TV or computer display (5 patients), driving car in the tunnel (4 patients), walking in supermarkets (4 patients) and walking through a crowd (2 patients). These findings indicate that the specific visual environments containing optical flow induced dizziness in VVS patients. Therefore, it is suggested that visual dependency on body sway is increased in VVS patients. We then developed a new device to produce optical flow stimulation to evaluate visual dependency on body sway. The ratio between sway path with eyes closed and eyes open is called the, Romberg ratio, which showed static visual dependency on, body sway. The Romberg ratio was increased in both healthy volunteers and VVS patients. On the other hand, the ratio between sway path with and without optical flow stimulation showed dynamic visual dependency on body sway. The ratio was markedly increased in some VVS patients, but not in other VVS patients and healthy volunteers. These findings suggested that the increased dynamic visual dependency on body sway is an important mechanism of the development of VVS