Research On The Value Of Directional Preponderance Of Caloric Test In Vertigo Diagnosis And Vestibular Compensation Evaluation

ObjectiveCaloric test is the most important inspection item in the diagnosis and treatment of vertigo,nystagmus directional preponderance(DP)is the chief parameter of caloric test,The abnormal result of directional preponderance had been considered as the characteristic of vestibular centra disease,but during the past few years we find it can also be the manifestation of the vestibular peripheral vertigo;we also find directional preponderance always appear with spontaneous nystagmus and unilateral weakness,these parameters have relation with vestibular compensation,on these grounds we suppose directional preponderance is also a parameter of vestibular compensation.We do vestibular function examination for vertigo patient who visit our department.The aim of this study is to analyze the value of directional preponderance in the diagnosis of vertigo and vestibular compensation evaluation.MethodWe consider the vertigo patient who visit our department between January 2006 and july 2007 as study object.There are 845 cases who had definite diagnosis,male 394 cases and 451 cases.We use Video-Nystagmography to trace the spontaneous nystagmus and do the caloric test routinely.We select directional preponderance, spontaneous nystagmus and unilateral weakness as the observation parameters,then analyze the distribution of the abnormal result of directional preponderance in the vestibular centra and peripheral disease;We do correlation analysis between DP and SN in the vestibular peripheral vertigo,also we do correlation analysis between DP and UW in the vestibular peripheral vertigo.Then we analyze the development of the three parameters with course of disease in the vestibular peripheral disease.Result1.There are 697 cases with vestibular peripheral disease and 148 cases with vestibular centra disease.There are 396 cases that the DP≥25%altogether,334 cases with vestibular peripheral disease and 62 cases with vestibular centra disease,x~2=1.78 (P＞0.05).There is no statistically significance.2.There are 104 cases that the DP≥25%and SN＞2°/s,95 cases DP and SN in the same direction and 9cases in the oppsite direction.(1).When DP had the same direction with SN,Spearman rank correlation coefficient is 0.556(P＜0.001),DP and SN have correlativity.(2).When DP had the oppsite direction with SN,there is only 9 cases.The major diagnosis of these cases is Meniere disease,vestibular neuronitis and sudden hearing loss.3.There are 241 cases that the DP≥25%and UW≥15%,98 cases DP and UW in the same direction and 143 cases in the oppsite direction.(1).When DP had the same direction with UW,Spearman rank correlation coefficient is 0.042(P＞0.05),DP and UW have no correlativity.(2).When DP had the oppsite direction with UW,Spearman rank correlation coefficient is 0.077(P＞0.05),DP and UW have no correlativity.4.The distribution of DP,UW and SN in the different stage of vestibular compensation and its correlativity with the course of disease:The course of disease in the different stage of vestibular compensation in the vestibular peripheral disease is skewness distribution.Their median is 2 days,6.5 days and 15days.Through Kruskal-Wallis Test,x~2=37.7(P＜0.001),there is statistical significance among the three stage.ConclusionDP of caloric test can be abnormal in the vestibular centra and peripheral disease,when diagnosis it must be consider other vestibular functional examination and Images etc;mostly DP has the same direction of SN,DP and SN have correlativity. The results suggest that DP is varying in the different stages of vestibular compensation,and DP can reflect the dynamic sensitivity of the vestibular system. This indicate DP can also be consider as the parameter of vestibular compensation. DP can guide the vestibular rehabilitation evaluation.