[Clinical comparative study of caloric test with water or air in healthyindividuals and diagnosing study on air caloric test].

Objective:To explore the equivalence of the test results of the water or air caloric tests and the compliance of the test in the healthy individuals. To provide scientific basis for clinical standardization of caloric test.Method: Randomized crossover clinical trial, 60 healthy individuals were divided into group A and group B. Water caloric test was carried out first in group A, and air caloric test was carried out after elution effect(one day interval). The treatment of group B was opposite to group A. SPV(Slow Phase Velocity), CP(canal paralysis) and SPV and CP' s 95%CI were used as evaluation indexes to analyze the equivalence of water and air caloric test in healthy people and the clinical normal reference value and stability and compliance of the water and air caloric test. Result: ①60 cases of caloric test CP value of chi square test suggested that there was no statistical difference between two kinds of media in the examination of the vestibular function of healthy individuals, and the CP value of the two was 85%(51/60). ②the SPV value of the was obviously higher than that of the air caloric test. The SPV value at each temperature of the water caloric test stimulation is quite different from the air caloric test stimulation. ③The range of water caloric test stimulation CP 95%CI was 8%-12%, and the average value was 10%. The interval of air caloric test stimulation CP 95%CI was 10%-15% and the average value was 12%. ④This study provided the corresponding SPV 95%CI as the medical reference values. ⑤The subjects of 98.33%(59/60) of the questionnaire survey selecting air caloric test and the results of the observation indicated that the duration of the air caloric test was shorter and more comfortable. Conclusion: ①Air caloric test can satisfied the needs of clinical assessment of horizontal semicircular canal function, and can make patients feel more comfortable. However, due to the weak intensity of nystagmus, water caloric test has to be used when the SPV value is too low. ②In this study, the upper limit of the CP value of the air caloric test in healthy individuals was 0.21, which is quite different from the upper limit of the standard value was 0.25 of the water caloric test. Therefore, the laboratory should establish their own reference value of the laboratory caloric test, and should not blindly apply the standard value of the water caloric test as the standard of the hemiplegia of the unilateral semicircular canal. The results of this study suggest that air caloric test can be used instead of water caloric test in clinic. And if the patient has no contraindications, air caloric test can be used as a priority.