Aimee双语小讲堂 第七讲：低血糖脑病

Aimee   上海某医院

History and CT images

History: A 22-year-old woman found down.

22岁女性，被发现时昏倒在地。

Head CT images are shown below. Click to enlarge.

MR images

Brain MR images without contrast are shown below. Images 1 through 6 are diffusion-weighted images with corresponding apparent diffusion coefficient (ADC) maps. Images 7 and 8 are fluid-attenuated inversion-recovery (FLAIR) images, and image 9 is a gradient-recall echo (GRE) image.

颅脑平扫核磁图像如下：弥散加权和相应的表观扩散系数图。黑水序列图，梯度回波序列图

Findings

· CT of the head: There is subtle diffuse hypoattenutation of the cerebral white matter.

· 头颅CT：脑白质密度弥漫性轻度减低。

· MRI of the brain:

· MRI shows diffuse restricted diffusion in the cerebral white matter, splenium of the corpus callosum, and internal capsules.

· There is subtle FLAIR signal abnormality in the caudate head.头颅核磁：

l 磁共振可见脑白质、胼胝体压部弥漫性弥散受限

l 黑水序列可见尾状核头轻度信号异常。

Differential diagnosis

· Hypoglycemia

· Hypoperfusion

· Posterior reversible encephalopathy syndrome (PRES)

鉴别诊断

l 低血糖

l 低灌注

l 可逆性脑病综合症

Diagnosis: Hypoglycemia

诊断：低血糖

Key points

Intracranial imaging manifestations of hypoglycemia in adults:

· Predominant involvement of the parietal/occipital lobes, hippocampi and amygdala gray matter, globus pallidus, and striatum characterized by T2 hyperintensity, gyral swelling, and restricted diffusion (may be transient). There is usual sparing of the thalami and white matter.

· However, there are few cases in the literature that describe symmetric involvement of the cerebral white matter, splenium of the corpus callosum, and posterior limb of the internal capsule in patients with prolonged hypoglycemia.

· Preferential involvement of the cerebral white matter over the basal ganglia or cerebral cortex can mean a better prognosis.

要点

成人低血糖的颅内影像学表现：

l 首先累及顶/枕叶，海马和杏仁核，苍白球和纹状体，呈T2高信号，脑回肿胀和弥散受限（可能一过性）。通常不累及丘脑和脑白质。

l 然而，文献中有罕见报道长期低血糖患者可见脑白质、胼胝体压部和内囊后肢对称性累及。

l 累及脑白质而非基底节或皮质指向更佳预后。