眩晕发作后婴儿型眼球震颤综合征的延迟表现。

文献信息

中文摘要

背景： 婴儿型眼球震颤综合征（INS），旧称先天性眼球震颤，通常在婴儿早期出现。我们报告一例罕见病例，其眼球震颤符合INS，但在青春期一次眩晕发作后才在临床上变得明显。方法：一名17岁女性出现急性旋转性眩晕。尽管眩晕逐渐消退，她仍持续感知到向右的视觉运动。五个月后，她因持续存在的自发性及凝视诱发性眼球震颤被转诊至我院。既往无眼球震颤病史或记录。结果：检查显示为急跳型水平性眼球震颤，以向右跳动的快相为主（慢相速度[SPV]约5°/s）。凝视试验显示方向改变性眼球震颤，以向左跳动为主（SPV 10-30°/s），并存在向右的中间位。水平平滑追踪呈扫视性，而垂直追踪保留。视动试验显示水平反应发育不良并出现倒转。前庭检查显示轻度右侧功能减退。在4年随访期间，轻度视振荡持续存在，眼动检查所见保持不变。结论：本病例提示，一次眩晕发作可能促成了青春期潜伏性INS的临床表现。持续存在的特征性眼动检查所见支持这样一种可能性：既存但临床上无声的INS可能在前庭功能障碍后变得明显。

英文摘要

Infantile nystagmus syndrome (INS), formerly referred to as congenital nystagmus, typically presents in early infancy. We report a rare case in which nystagmus consistent with INS became clinically apparent after a vertigo attack during adolescence. A 17-year-old female developed acute rotational vertigo. Although the vertigo gradually subsided, she continued to perceive rightward visual motion. Five months later, she was referred to our institution because of persistent spontaneous and gaze-evoked nystagmus. There was no prior history or documentation of nystagmus. Examination revealed jerk-type horizontal nystagmus with a predominantly right-beating fast phase (slow-phase velocity [SPV] ~5°/s). Gaze testing showed direction-changing nystagmus, predominantly left-beating (SPV 10-30°/s), with a rightward null position. Horizontal smooth pursuit was saccadic, whereas vertical pursuit was preserved. Optokinetic testing demonstrated poor development and inversion of horizontal responses. Vestibular testing showed mild right-sided hypofunction. Over a 4-year follow-up, mild oscillopsia persisted, and ocular motor findings remained unchanged. This case suggests that a vertigo attack may have contributed to the clinical manifestation of latent INS in adolescence. Persistent characteristic ocular motor findings support the possibility that pre-existing but clinically silent INS may have become manifest following vestibular dysfunction.