J Korean Soc Radiol.  2019 Nov;80(6):1247-1252. 10.3348/jksr.2019.80.6.1247.

High-Altitude Cerebral Edema Evaluated with MRI: A Case Report

• Hwang S
• Lee BH
• Hwang YJ
• Kim JW

• KMID: 2464922
• DOI: http://doi.org/10.3348/jksr.2019.80.6.1247

Abstract

High-altitude cerebral edema (HACE) is a rare life-threatening condition observed in individuals who climb high altitudes. This report describes the case of a 38-year-old man who recently climbed a 5000-m-high mountain, showing the following radiologic findings at 3 different anatomical locations: 1) increased T2 signal intensity (SI) without restricted diffusion, with full recovery in the posterior limb of the left internal capsule; 2) increased T2 SI with restricted diffusion, with full recovery in the splenium of the corpus callosum; and 3) increased T2 SI with restricted diffusion and microbleeds, resulting in bilateral encephalomalacia in the globus pallidus. Herein, we report the concurrent typical and atypical radiologic findings of this rare condition caused by vasogenic and cytotoxic edema.

MeSH Terms

Adult
Altitude
Brain Edema*
Corpus Callosum
Diffusion
Edema
Encephalomalacia
Extremities
Globus Pallidus
Humans
Internal Capsule
Magnetic Resonance Imaging*

Figure

• 

  Fig. 1 CT and MRI findings of a 38-year-old man with general weakness and urinary incontinence after climbing a 5000-m-high mountain. A. Axial CT scan image shows low attenuation in bilateral globus pallidus (arrowheads) and the splenium of the corpus callosum (arrow). B. Axial T2WI shows a high SI in bilateral globus pallidus (arrowheads), the posterior limb of the left internal capsule (arrow in the middle image), and the splenium of the corpus callosum (arrow in the right image). C. Axial FLAIR image shows high SI in bilateral globus pallidus (arrowheads), the posterior limb of the left internal capsule (arrow in the middle image), and the splenium of the corpus callosum (arrow in the right image). D. There are high SIs on the axial DWI image of high b-value (1000 s/mm2) and dark SI on the axial ADC map, revealing diffusion restriction in bilateral globus pallidus (arrowheads) and the splenium of the corpus callosum (arrows). E. Axial GRE image shows dark SI with microbleeds in bilateral globus pallidus (arrowheads). No abnormal SI is noted in the posterior limb of the left internal capsule (arrow in the middle image) and splenium of the corpus callosum (arrow in the right image). F. Follow-up axial DWI of high b-value (1000 s/mm2) and ADC map images show focal encephalomalacia in bilateral globus pallidus (arrowheads), contrary to the fully recovered previously restricted diffusion in the splenium of the corpus callosum (arrows). FLAIR = fluid-attenuated inversion recovery, SI = signal intensity, T2WI = T2-weighted image, ADC = apparent diffusion coefficient, DWI = diffusion-weighted imaging, GRE = gradient echo sequences, SI = signal intensity

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