Conjugate eye deviation (CED) is defined as a sustained shift in horizontal gaze toward 1 side, together with gaze failure to the other side, caused by lesions in the brainstem, basal ganglia, or cortical frontal eye fields. To date, very few reports have described CED in patients with medullary infarction. A 76-year-old woman presented with sudden onset of vertigo and right hemiparesis, accompanied by CED to the right with gaze palsy to the left. Her brain magnetic resonance imaging showed left upper medial medullary infarction involving the left nucleus prepositus hypoglossi (NPH) and adjacent to the left inferior olivary nucleus (ION). After treatments with 200 mg of aspirin and 60 mg of edaravone daily, symptoms gradually improved. The NPH and ION constitute NPH-ION-floccus-vestibular nucleus loop and contribute to the inhibitory mechanisms for horizontal eye movements. In addition, NPH projects excitatory neurons to the contralateral vestibular nucleus. In our case, disorders of the NPH and ION might have dysregulated inhibitory and excitatory projections, and thereby cause CED to the right with gaze palsy to the left. This represents a rare case showing CED to the contralesional side in upper medial medullary infarction.

中文翻译：

---

共轭眼球引起的上内侧髓腔梗死的偏斜：一例报告。

共轭眼偏差（CED）的定义是水平凝视向一侧持续移动，而凝视向另一侧凝视失败，这是由脑干，基底神经节或皮质额叶视场病变引起的。迄今为止，很少有报道描述髓样梗死患者的CED。一名76岁的女性，突然出现眩晕和右半身偏瘫，右侧伴有CED，左侧为凝视麻痹。她的脑磁共振成像显示左上内侧髓样梗塞，累及左核前垂肌（NPH），并邻近左下橄榄核（ION）。每天用200毫克阿司匹林和60毫克依达拉奉治疗后，症状逐渐改善。NPH和ION构成NPH-ION-絮凝物-前庭核环，并有助于抑制水平眼球运动。此外，NPH将兴奋性神经元投射到对侧前庭核。在我们的案例中，NPH和ION的疾病可能抑制和兴奋性投射失调，从而导致CED移至右侧，而凝视麻痹则移至左侧。这代表了罕见的病例，在上内侧髓样梗死中向对侧显示CED。