A 24-year-old woman presented with blurry vision. Examination showed left eye esotropia and slow horizontal saccades bilaterally. Vertical saccade velocity was normal, and there was a "round the houses" sign on diagonal saccades (Video 1). Video head impulse testing (vHIT) reduced gains in the posterior canals bilaterally with relative preservation of anterior and horizontal canal function bilaterally.

中文翻译：

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NeuroImage 教学视频：对角扫视测试可以定位慢速扫视

一名 24 岁女性出现视力模糊。检查显示左眼内斜视和双侧缓慢水平扫视。垂直扫视速度正常，对角扫视有“绕房子”标志（视频 1）。视频头脉冲测试（vHIT）减少了双侧后根管的增益，同时相对保留了双侧前根管和水平根管功能。