我们报告了一例82岁女性患者，表现为亚急性意识障碍、眼运动障碍和共济失调。检查发现，她表现为双侧眼睑下垂，完全的水平性眼肌麻痹和限制上视的垂直眼动，并伴有明显的躯干共济失调。脑 MRI 检查显示后脑干向上颈段脊髓方向轻微的 T2 异常信号和液体衰减反转序列，但没有钆增强。临床和影像学特征提示存在脑干炎症性脑脊髓炎。我们总结了亚急性脑干炎症患者的详细鉴别诊断，包括感染性、肿瘤相关综合征和炎症性疾病。该病例强调在未发现肿瘤的初步检查中执行广泛而系统的筛查的重要性。© 2023 美国神经病学学会。

We present a case of an 82-year-old female with subacute altered mental status, oculomotor disturbances, and ataxia. On examination, she exhibited bilateral ptosis, complete horizontal ophthalmoplegia and limited vertical eye movements during upgaze associated with prominent truncal ataxia. Cerebral MRI showed a mild hyperintensity on T2 and fluid attenuated inversion recovery sequences in the posterior brainstem extending to the upper cervical cord, without gadolinium enhancement. Clinical and radiological features suggested an encephalomyelitis with prominent brainstem involvement. We summarize the comprehensive differential diagnosis in patients with subacute brainstem encephalitis, that includes infectious, paraneoplastic syndromes and inflammatory disorders. This case highlights the relevance of performing a wide, methodical screening for malignancy in case of negative initial work-up.© 2023 American Academy of Neurology.