前庭性偏头痛患者位置性眼震的特征分析

目的 观察研究前庭性偏头痛(VM)患者位置性眼震的临床特征,探讨其可能机制.方法 回顾性分析经视频眼震图(VNG)记录的14例急性发作期VM患者和16例水平半规管良性阵发性位置性眩晕(HSC BPPV)患者在Dix-Hallpike试验和滚转试验(Roll-test)诱发下位置性眼震的类型、强度、时问等参数.结果 VM患者于多种诱发体位时出现混合性的眼震成分,其眼震成分主要为下跳性、离地性及向地性成分的单个或多个组合.VM组和HSC-BPPV组眼震的潜伏期、持续时间差异均无统计学意义(P＞0.05).VM组水平成分的眼震最大慢相角速度(SPVmax)为(11.4±2.3)°/s,低于HSC BPPV组(56.8±9.4)°/s],两组比较差异有统计学意义(P=0.001).与HSC-BPPV组相比,VM组达到SPVmax时所需的时间(tm)较长(18.1±2.0) svs (5.9±1.1)s,P＜0.001],其眼震变化速率较缓慢(0.54±0.14)°/s2vs (7.21±1.79)°/s2,P＜0.001].HSC-BPPV组的强弱侧眼震强度的不对称比高于VM组,差异有统计学意义(P=0.02).结论 VM中异常的中枢整合机制可能引起紊乱的半规管旋转信息传递,导致变位试验时出现混合性眼震成分以及多种体位诱发的平坦型眼震.

Characteristic analysis of positional nystagmus in patients with vestibular migraine

Objective To analyze the characteristics of positional nystagmus in patients with vestibular migraine (VM) and to discuss its possible mechanism. Methods We retrospectively analyzed the types, intensities, and time of positional nystagmus recorded by video nystagmography during Dix-Hallpike and Roll-test in 14 patients with acute episode of VM and 16 patients with benign paroxysmal positional vertigo (HSC-BPPV). Results A mixture of geotropic, apogeotropic and downbeat components with a variable combination of each component and various types of positional nystagmus were identified in VM. There was no significant difference in the latencies or the duration of positional nystagmus between VM group and HSC-BPPV group (P>0.05). The peak slow-phase velocities (SPV_max) in horizontal component of positional nystagmus was (11.4±2.3)°/s in VM group, which was significantly lower than that in the HSC-BPPV group (56.8±9.4]°/s, P=0.001). Compared with HSC-BPPV group, the time needed for reaching the SPV_max (t_m) was significantly longer in VM group (18.1±2.0] vs5.9±1.1] s, P<0.001), and the rate of velocity change was significantly slower in VM group (0.54±0.14] vs7.21±1.79]°/s², P<0.001). The asymmetry ratio of the stronger to softer SPV_max in HSC-BPPV group was significantly higher than that in the VM group (P=0.02). Conclusion Abnormal central integration mechanism in VM may lead to discordant transmission of semicircular canal rotation information, resulting in mixed nystagmus components and flat nystagmus that appeared at multiple positional maneuver.