[The significance of directional preponderance in the evaluation of vestibular function in patients with vertigo].

Objective: To analyze the relationship between directional preponderance (DP), spontaneous nystagmus(SN) and vestibular disorders, and to investigate the significance of DP in directing peripheral vestibular function in patients with vertigo. Methods: This was a retrospective analysis of 394 cases diagnosed with peripheral vestibular disease accompanied by vertigo from March 2012 to June 2014 in the Outpatient Department of the Eye & ENT Hospital of Fudan University. Results of static and dynamic posture equilibrium tests, SN, unilateral weakness(UW), and DP in videonystagmography(VNG) were analyzed and compared. Results: The mean interval time between the last vertigo attack and examination in patients with SN or DP in caloric test were 4.4 d and 7.3 d respectively, and those without SN or DP were 18.3 d and 17.5 d respectively. The patients were divided into two groups according to DP results of caloric test. DP-normal group had 203 cases and DP-abnormal group had 191 cases. Spontaneous nystagmus was presented in 44 cases in the DP-normal group (21.67%) and four in the DP-abnormal group (2.09%). A significant difference was found between the two groups (χ2=35.27, P=0.000). Deficiency of vestibular function was noted in 165 cases in the DP-normal group (81.28%) and 123 (64.40%) in the DP-abnormal group in static and dynamic posture equilibrium tests. The difference between the two groups was statistically significant (χ2=14.26, P=0.000). Conclusion: Compared with DP-normal patients, DP-abnormal patients are more likely to have spontaneous nystagmus and balance disorders due to vestibular dysfunction.目的：分析变温试验优势偏向(directional preponderance, DP)与自发性眼震(spontaneous nystagmus, SN)和前庭觉障碍的相关性，明确DP与外周性眩晕患者疾病所处时期的关系，探讨其在前庭功能评估中的意义。 方法：收集2012年3月至2014年6月于复旦大学附属眼耳鼻喉科医院门诊就诊的外周性眩晕患者394例，比较动静态姿态平衡台感觉结构以及视频眼震电图(videonystagmography, VNG)测试中SN、半规管功能减弱(unilateral weakness, UW)及DP的结果，并进行统计学分析。 结果：在变温试验中，有SN和DP的患者其末次眩晕发作时间与检查相距的时间分别平均为4.4 d和7.3 d，而无SN和DP的患者平均时间分别为18.3 d和17.5 d。根据是否存在DP，将患者分为两组，其中DP组203例、无DP组191例。比较两组SN的发生率，DP组21.67%(44/203)、无DP组2.09%(4/191)，差异具有统计学意义(χ2＝35.27，P＝0.000)。在DP组中，动静态姿态平衡台感觉结构测试提示前庭功能不足者165例(81.28%)，无DP组中前庭功能不足者123例(64.40%)，组间差异具有统计学意义(χ2＝14.26，P＝0.000)。 结论：变温试验DP阳性患者更易发生SN和前庭觉不足导致的平衡障碍；DP可能和SN一样，与外周性眩晕患者疾病所处的发作时期有关。.