水平半规管BPPV患者复位前后冷热试验临床分析

A Clinical Analysis of Bithermal Caloric Tests before and after the Reduction of Benign Paroxysmal Positional Vertigo Patients with Horizontal Semicircular Canals

目的探讨耳石的存在对原发性水平半规管良性阵发性位置性眩晕(horizontal semicircularcanal benign paroxysmal positional vertigo,HC-BPPV)患者复位前、后前庭功能的影响。方法随访2014年8月~2015年3月就诊于我科门诊并确诊为原发性HC-BPPV患者51例,复位前进行双耳交替冷热试验检测了解前庭功能,复位成功后再次进行双耳交替冷热试验检测了解前庭功能,以半规管轻瘫(canal paresis,CP)值作为评定参数,CP≥25%为异常,考虑该侧半规管轻瘫。结果随访患者中有36例在复位前冷热试验显示半规管轻瘫,其中30例出现健侧半规管轻瘫,6例出现患侧半规管轻瘫,健侧CP发生率高于患侧,两者差异具有统计学意义(P=0.000<0.001),提示BPPV复位前患侧前庭兴奋性高于健侧;15例患者复位前冷热试验显示双侧前庭功能大致对称。复位一周后复查变位试验及冷热试验结果显示51例患者均为阴性,双侧前庭功能对称;两者差异具有统计学意义(P=0.000<0.001)。结论水平半规管管型BPPV患者的前庭功能由于耳石的影响存在暂时性的可逆性的改变,耳石的存在增加内淋巴液的流动惯性从而增加对壶腹嵴的刺激可能是HC-BPPV患者患侧前庭兴奋增高的原因。

Objective To investigate the impacts of the otolith on the vestibular function before and after the repositioning maneuvers in patients with primary horizontal semicircular canal benign paroxysmal positional vertigo（HC-BPPV）. Methods The 51 patients visiting our dizziness clinic were diagnosed with primary HC-BPPV from August 2014 to March 2015. All of them completed bithermal caloric tests before the canalith repositioning maneuvers and retests after the repositioning maneuvers to understand the function of vestibular. The canal paresis（CP） values were selected as the prima parameter. It was considered abnormal when the CP value was equal to or greater than 25%. Results There were 36 patients with canal paresis,including 6 patients with ipsilateral canal paresis（CP〉25%） and 30 patients with contralateral canal paresis before the repositiouing maneuvers. The incidence of canal paresis on the intact side was higher than the affected side with significant differences, indicating the vestibular excitability on the affected side was stronger than the non-affected side before the repositioning maneuvers. 15 patients examined by bithermal caloric tests showing the bilateral vestibular function was roughly symmetrical. All 51 patients showed no canal paresis after the maneuvers, and the difference was statistically significant （P〈0.001）. Conclusion The vestibular function of the patients with the canalolithiasis type of HC-BPPV was temporarily and reversibly affected by the otoliths. The otoliths increased the flow inertia of the endolymph; therefore, the stimulation to the crista ampullaris became stronger which may cause the increase of lateral vestibular excitability of the HC-BPPV patients.