目的：分析轻嵴帽患者眼震消失平面（NP）的临床特征。方法：纳入仰卧滚转试验表现为持续性向地 性变向性位置性眼震且有NP的患者28例；在眼震视图下行观察其动态位置性眼震特征，并寻找NP进行定 侧诊断；给予手法复位，并于首次复位后1周及1个月随访，观察患者的转归。结果：28例轻嵴帽患者中，11 例（39.3%）有自发眼震；10例（35.7%）有NP1，28例（100%）有NP2和NP3，且患者对NP2检测时的耐受性较 好；首次复位有效率为7.1%，1周随访有效率为14.3%，1月随访有效率100%。结论：NP2检测是轻嵴帽诊断 及定侧诊断的简便、可行的方法；轻嵴帽患者复位效果差，但病程多呈自限性。

To analyze the clinical characteristics of null point (NP) in patients with the light cupula. Methods: Twenty-eight patients with light cupula diagnosed by Supine-Roll test were included in this study. All patients underwent videonystagmusgraphy to observe the characteristics of their dynamic positional nystagmus, and to find the nystagmus disappearing plane, that is, the NP, to make a lateralization diagnosis. All patients were followed up to assess the effects of manual reduction treatment. Results: In the 28 cases, 11 (39.3%) presented with spontaneous nystagmus, 10 (35.7%) had NP1, 28 (100%) had NP2 and NP3. Moreover, patients had a good tolerance to NP2 evaluation. The effective rate was 7.1% after first-time manual reduction, 14.3% at one-week follow-up, and 100% at one-month follow-up. Conclusion: The evaluation of NP2 is a simple and effective method for the diagnosis of the light cupula and the lateralization diagnosis. The patients with light cupula have poor response for manual reduction treatment. However the course of disease is mostly self-limiting