A 52-year-old man presented with acute onset of primarily anterograde amnesia. He had a history of diabetes mellitus, coronary artery disease and smoking. We found no other focal neurological deficits. The amnesia improved slowly over the subsequent weeks. MR scan of the brain showed moderate chronic microangiopathic white matter changes and acute infarction in both fornices (figure 1). This most likely explained the abrupt onset of anterograde amnesia and prolonged recovery. Figure 1 Axial diffusion weighted MRI (A) and apparent diffusion coefficient image (B) showing the acute diffusion restriction in both fornices (arrows), consistent with bilateral acute fornix infarction. ### Anatomy and function The fornices are white matter tract bundles that lie on the medial aspects of the cerebral hemispheres. They each contain output fibres arising …

中文翻译：

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不要忘记穹窿

一名 52 岁男性因急性发作的主要顺行性遗忘症就诊。他有糖尿病、冠状动脉疾病和吸烟史。我们没有发现其他局灶性神经功能缺损。在接下来的几周里，健忘症慢慢好转。脑部 MR 扫描显示两个穹窿中度慢性微血管病变性白质改变和急性梗死（图 1）。这很可能解释了顺行性健忘症的突然发作和长时间的恢复。图 1 轴向弥散加权 MRI (A) 和表观弥散系数图像 (B) 显示双侧穹窿的急性弥散受限（箭头），与双侧急性穹窿梗塞一致。### 解剖结构和功能 穹窿是位于大脑半球内侧的白质束束。它们每个都包含产生的输出纤维……