Discussion Of The Evaluation Methods Of Horizontal Semicircular Canal

Objective: There are a lot of methods to evaluate the semicircular canal function,the detect frequency range are not identical in different detection technology. To analyze the sensitivity, specificity, relationship and the clinical diagnostic value of the four commonly used testing means of semicircular canal function, namely caloric test(CT),rotatory test, head shaking nsytagamus test(HSN) and video head impulse test(v HIT)are studied.Methods: The retrospective analyze were carried out to 227 cases of vertigo patients to the hospital of otolaryngology. After conventional history, ear endoscope and audiological examination, further examination of caloric test, rotatory test, head shaking nsytagamus test and video head impulse test were needed. In order to understand the sensitivity, specificity, detection results, characteristics, relationship and the clinical diagnostic value of v HIT, HSN and rotatory test, the caloric test was considered as a“gold standard”.Results: 1. Compared with the caloric test, the sensitivity and specificity analysis of v HIT, HSN and chair test(1) sensitivity analysis: 96 patients were carried out v HIT and caloric test at the same time, v HIT horizontal semicircular canal function abnormalities in 64 cases, the sensitivity was 67%, caloric test abnormal 49 cases, the sensitivity was51%, the difference was statistically significant(P = 0.04, < 0.05), v HIT sensitivity is higher than the caloric test;197 cases of patients with HSN test and caloric test examination at the same time, HSN test abnormalities in 101 cases, the sensitivity was51%, caloric test, 95 cases of abnormal, the sensitivity was 48%, there was no statistically significant difference(P = 0.749 > 0.749); 60 patients with rotatory chair and caloric test examination at the same time, the rotatory chair abnormal results 34 cases, the sensitivity was 57%, 30 cases of abnormal caloric test the sensitivity was50%, there was no statistically significant difference(p = 0.608 > 0.608).Namely v HIT,caloric test, HSN test and rotatory chair test, v HIT sensitivity is highest, the remaining three kinds of detection means no significant.(2) record caloric test as a reference, the sensitivity and specificity analysis of v HIT, HSN and rotatory chair test: sensitivity and specificity of v HIT: 49 cases are abnormal in the caloric test,while 33 cases dysfunction in the horizontal semicircular canal of v HIT, 16 cases of normal; 47 patients are normal in caloric test while v HIT horizontal semicircular canal dysfunction 31 cases, 16 cases of normal.Sensitivity and specificity of HSN test: 95 patients are abnormal in caloric test,while 55 cases positive in HSN test, 40 cases negative; 102 cases of patients caloric test are normal as HSN test positive46 cases,negatie 56 cases.Sensitivity and specificity of rotatory chair test: 30 cases are abnormal in caloric test results of 15 cases of rotatory chair test are normal patients with 15 cases are abnormal; 30 cases of patients normal in caloric test, results of 19 cases, abnormal and 11 cases normal in rotatory chair test.The sensitivity and specificity of v HIT 、HSN and rotatory chair test were 67% and 34%、58% and 55% 、50% and 37%.2. According to the semicircular canal paresis(CP)degree of caloric test, the sensitivity of v HIT, HSN and rotatory test show bellow(1) 96 cases of patients had both caloric test and v HIT, 47 cases of CP value normal(≦ 20%), 26 cases had mild semicircular canal paresis(< 20% CP ≦ 45%),12 cases had moderate semicircular canal paresis(<45% CP ≦ 75%),11 cases had severe semicircular canal paresis(CP > 75%),but horizontal semicircular canal function of v HIT abnormal namely were 31 cases(66%),14(54%),8(67%),11(100%)。(2)197 cases had HSN and caloric test, 101 cases of patients with CP value normally(≦ 20%), 53 cases had mild semicircular canal paresis(20%<CP ≦ 45%), 24 cases had moderate semicircular canal paresis(45%<CP ≦ 75%),19 cases had severe semicircular canal paresis(CP > 75%),while HSN test abnormal namely were 46 cases(46%),23 cases(43%), 16(67%),16( 84%).(3) 60 cases both had caloric test and rotatory test, 30 cases CP value normally(≦ 20%), 17 cases had mild semicircular canal paresis(20%<CP ≦ 45%),7 cases had moderate semicircular canal paresis(45%<CP ≦ 75%), 6 cases had severe semicircular canal paresis(CP> 75%), while the rotatory test abnormal were 19( 63%),7 cases( 41%),2cases(29%), 6 cases( 100%).AS the caloric test semicircular canal paresis classification,horizontal semicircular canal of v HIT 、 HSN and rotatory test dysfunction rate or sensitivity difference were statistically significant(x2were10.761, 11.268 and 14.087, p< 0.05).Thus, vestibular damage can occur alone in low frequency, intermediate frequency and high frequency;As low damage degree aggravating, medium frequency,high-frequency damage probability increased significantly.3. Four kinds of detection means are carried out on patients the same time: in this study,32 cases of patients had caloric test, rotatory test, HSN and v HIT: the consistency value all below 0.4, P > 0.05, no statistical significance. Therefore, four kinds of detection methods, the consistency between two are poor.Therefore, in clinical work, we need to joint the detection technology, comprehensive evaluation the function of vestibular system.Conclusions: 1. v HIT horizontal semicircular canal function sensitivity is highest, but there was no difference in the sensitivity of caloric test, rotatory test and HSN.2. The vestibular damage can occur alone in low frequency, intermediate frequency and high frequency;With low damage degree aggravating, medium frequency,high-frequency damage probability increased significantly.3. The consistency of the four kinds of detection means are poor, in clinical work, we need joint the detection technology, comprehensive evaluation the function of vestibular system.