THE EFFECT OF LOW FREQUENCY SOUND ON POSTURAL STABILITY IN PATIENTS WITH VERTIGO CAUSED BY INNER EAR DYSFUNCTION.

为探讨低频声对不同类型内耳病变患者体位稳定性的影响。低频声级130~132分贝，频率为4、8、16、25、50、63赫兹。用测力台测量体位反应，测定力中心点的摆动速度。在健康受试者中，低频声刺激不会增加身体的摇摆速度。在刺激期间，受试者的姿势稳定性略有改善，可能是由于低频声音刺激产生的警觉反应所致。梅尼埃病、慢性中耳炎伴眩晕和周围性眩晕患者的平均反应在刺激时身体摇摆增加。在个体反应中，26%的梅尼埃病患者、40%的慢性中耳炎眩晕患者、26%的周围性眩晕患者在低频声刺激下出现明显的姿势不稳定。所有外淋巴瘘患者在低频刺激时体位稳定性均有明显改变。结果表明，在不同类型的内耳疾病受试者中，前庭系统开始对低频声音产生反应。低频声对前庭脊髓反应的激活似乎是图利奥现象的一种表现。从专业林业工作者群体中随机选取80名受试者，研究吸烟对体位稳定性的长期影响。年龄和吸烟与摇摆速度有显着的简单相关，但暴露在噪音中的小时数没有相关性。平均摇摆速度随吸烟量的增加而增大。吸烟者比不吸烟者表现出更不稳定的姿势描记结果。吸烟被认为对姿势控制系统有长期影响。

The effect of low frequency sound on postural stability was studied in patients with different type inner ear pathology. The low frequency sound level ranged from 130 to 132 dB and were delivered at the frequencies 4,8,16,25,50,63Hz. The postural response were measured with a force platform and the sway velocity of the center point of force was determined. In the healthy subjects, the low frequency sound stimulation did not increase body sway velocity. The subjects showed slight improvement of their postural stability during the stimulation period, probably due to alerting response generated by the low frequency sound stimulation. The mean responses of patients with Meniere's disease, with chronic otitis media with vertigo and with vertigo of peripheral origin showed increased body sway during stimulation. In the individual response 26% of the patients with Meniere's disease, 40% with chronic otitis media with vertigo, 26% with vertigo of peripheral origin experienced significant postural instability during the stimulation of low frequency sound. All patients with perilymphatic fistula showed significantly altered postural stability during low frequency stimulation. The result demonstrate that in subjects with different types inner ear disease the vestibular system starts to respond to low frequency sound. The activation of vestibulospinal responses by low frequency sound seems to be an expression the Tullio phenomenon. A long term effect on smoking on postural stability was examined on 80 subjects randomly selected from a population of professional forest workers. Age and smoking had significant simple correlation coefficients to sway velocity but hours of exposure to noise did not. The mean sway velocity increased with increase the dose of smoking. Smokers exhibited more unstable posturographic results than non-smokers. Smoking was suggested to have long term effect on the postural control system.