[The analysis of the value of　spontaneous nystagmus in peripheral vestibular hypofunction].

Objective:To study the characteristics and clinical value of spontaneous nystagmus in patients with peripheral vestibular dysfunction.Method:Sixty cases with acute unilateral peripheral vestibular dysfunction were studied.All were diagnozed as vestibular neuritis(VN) . The relationship between SN and disease duration,DP and UW were analyzed.Result:SN was present in49 patients(81.7%)and absent in the remaining 11(18.3%).The intensity of SN ranged from 0.5°/s-20.4°/s and had negative correlation with the disease duration(r=-0.478，P<0.01). The patients were divided into 3 groups (mild,medium and severe) according to SN intensity,with median duration of disease being 6.5 d，5 d and 3 d respectively. The difference between groups was statistically significant(χ²=9.071，P<0.01).The result of the caloric test were as following：caloric test revealed DP in 44 cases（89.8%） of SN ;DP values were normal in 8 cases（10.2%）;SN intensity was positively correlated with DP value（r=0.513,P<0.01） ;unilateral weakness was found in 35 cases（71.4%）,with the direction of SN towards the weakness side in 4 cases and towards the opposite direction in the remaining 31 cases; 7 cases（14.3%）had bilateral weakness and 7 cases（14.3%）normal. There were no relationship between the intensity of SN and UW value（r=-0.321,P>0.05）.The UW value of patients with SN (40.9±26.3）% was compared to the group without SN（29.9±18.2）% . The difference was statistically significant (F=4.497,P<0.05).Conclusion:The intensity of SN in patients with acute unilateral peripheral vestibular dysfunction was often moderate and severe. The intensity of SN waned as the disease progressed or the direction reversed,The vestibular injury in patient with SN was more severe than those without. SN is useful in clinical assessment of vestibular injury and compensatory status.