Hypoglycemia and Diffusion-Weighted Imaging

Abstract

The effect of severe hypoglycemia on the brain is well known, ranging from alterations of mental status to profound coma and death. We describe a case of global diffusion abnormalities eventually resulting in death. This otherwise healthy patient presented with seizures and a serum glucose level less than 20 mg/dL. Testing suggested that the hypoglycemia was likely caused by exogenous insulin or perhaps insulin receptor antibodies. Magnetic resonance imaging on the day after admission showed regions of restricted diffusion in the temporal and occipital lobes as well as in the basal ganglia. Despite the large body of literature concerning the pathophysiology of hypoglycemia and its clinical implications, little is known regarding its radiologic correlations.

Diffusion MR Imaging of Hypoglycemic Encephalopathy

“…17 Some authors have reported DWI and ADC findings of HE. [1][2][3][5][6][7][8][9][10][11][12][13][14][15][16]18 According to previous reports, the lesions show reversible cytotoxic edema at the cerebral cortex, 14,15,18 hippocampus, 19 splenium, 7,11,12,16 IC, 13,16 and cerebral WM. 5,8 These diffusion alterations are encountered not only in acute ischemia but also in hypoglycemia itself, and in vivo animal model studies have demonstrated diffusion alterations due to hypoglycemia.…”

“…3,6,16,17 If hyperintensity lesions are detected in WM such as the CC, IC, or CR and the hyperintensity lesions regress on follow-up images, the patient will likely recover without a neurologic deficit. 5,7,16 However, if lesions are detected in the cerebral cortex, BG, or hippocampus and the lesions do not regress on second imaging, the outcome will be poor.…”

“…[1][2][3] Neuropathologic studies have demonstrated that the cerebral cortex, hippocampus, and BG are commonly affected sites in severe hypoglycemia; however, the cerebellum and brain stem are usually spared. [4][5][6][7][8][9][10] In addition, unlike hypoxic damage, the occipital cortex, dorsofrontal cortex, and hippocampus may be more resistant to prolonged hypoglycemia. 9 Some studies have described MR imaging of hypoglycemic brain injury, though these studies have usually been confined to case reports; in most of the reported studies, DWI is useful in evaluating severe HE.…”

“…Reversible diffusion restriction has been found in most cases. 1,[5][6][7][10][11][12][13][14][15][16] However, most studies have been case reports, and MR imaging features of hypoglycemic brain injury have not been fully established. The purpose of this study was to determine the topographic distribution and DWI findings of HE.…”

Reversible Diffusion-Weighted Imaging Changes in the Splenium of the Corpus Callosum and Internal Capsule Associated With Hypoglycemia -Case Report-

“…Therefore, we attributed the clinical symptoms and MR imaging findings to hypoglycemia. MR imaging has previously detected lesions associated with hypoglycemia in the cerebral cortex, basal ganglia, and hippocampus, 4,7,8,10,15,18) mostly with poor outcome resulting in death or persistent vegetative state. These regions are known to be the most vulnerable to hypoglycemic insult.…”