■了解眼部重症肌无力(OMG)的病理生理学对改善治疗很重要。
■为了使用现代视频眼图来描述OMG患者的眼跳运动,包括抗AChR,反MuSK,抗LRP4和血清阴性OMG。
■总共,21名OMG患者和5名年龄匹配的健康对照受试者进行了视频眼图检查。参与者在±5°处进行了一系列水平扫视(每次3分钟),±10°,和±20°,然后在±5°处对随机呈现的目标进行3分钟的扫视,±10°,±15°。我们记录了方向,振幅,持续时间,峰值,以及每个参与者的每个任务的每个扫视的平均速度。
■扫视振幅,持续时间,OMG患者的平均速度均低于对照组(p<0.021)。Saccadic振幅和速度随时间下降,但OMG患者和对照组的这种减少是相似的.OMG患者的固定漂移和眼差倾向于大于对照组。与对照组相比,OMG患者的扫视侵入发生率更高(p<0.001)。没有发现时间或时间对固定漂移或眼差的显着影响。
■OMG患者的扫视速度与正常对照组不同,这表明OMG会影响快速抽搐纤维,尽管在严重眼肌麻痹的情况下,快速抽搐纤维仍然能够产生“抽搐”或“颤抖”运动。牵制凝视的慢抽搐肌纤维也受到影响,考虑扫视后固定漂移的增加。我们的客观发现增加的固定漂移和大量的扫视侵入反映了我们对OMG患者的轶事经历,尽管检查时出现了轻微的眼肌麻痹,但他们报告了明显的复视。这种微扫视可能是补偿MG凝视不足的代用品。
UNASSIGNED: It is important to understand the pathophysiology of ocular myasthenia gravis (OMG) to improve treatment.
UNASSIGNED: To use modern video-oculography to characterise saccadic eye movements in patients with OMG, including anti-AChR, anti-MuSK, anti-LRP4, and seronegative OMG.
UNASSIGNED: In total, 21 patients with OMG and five age-matched healthy control subjects underwent video-oculography. Participants performed a sequence of horizontal saccades (3 minutes each) at ±5°, ± 10°, and ±20°, followed by 3 minutes of saccades directed at randomly presented targets at ±5°, ± 10°, and ±15°. We recorded the direction, amplitude, duration, peak, and average velocity of each saccade for each task for each participant.
UNASSIGNED: Saccadic amplitude, duration, and average velocity were all lower in OMG patients than in control subjects (p < 0.021). Saccadic amplitude and velocity decreased over time, but this decrease was similar in OMG patients and control subjects. Fixation drift and ocular disparity tended to be greater in OMG patients than in control subjects. Saccadic intrusions occurred more frequently in OMG patients than in control subjects (p < 0.001). No significant effects of time or group by time on fixation drift or ocular disparity were found.
UNASSIGNED: Saccadic velocities in OMG patients differed from those in normal control subjects, which suggests that OMG affects fast-twitch fibres, although fast-twitch fibres were still able to generate \"twitch\" or \"quiver\" movements in the presence of even severe ophthalmoplegia. Slow-twitch muscle fibres involved in gaze holding were also affected, accounting for increased fixation drift following saccades. Our objective finding of increased fixation drift and a larger number of saccadic intrusions mirror our anecdotal experience of patients with OMG who report significant diplopia despite minimal ophthalmoplegia on examination. Such microsaccades may be a surrogate for compensation of a gaze-holding deficit in MG.