Magnetic resonance imaging findings in patients with non-ketotic hyperglycaemia and focal seizures

Abstract

We present the neuroimaging findings of three cases of non-ketotic hyperglycaemia (NKH) associated with focal seizures and a review of the previous cases and series reported in literature. NKH is a cause of seizures in both long-standing and newly diagnosed diabetic patients. They are usually focal motor seizures, rarely with a secondary generalisation. This condition does not fully respond to anticonvulsant therapy if glycaemic levels are not normalised. Of interest, magnetic resonance imaging (MRI) of NKH could be different from those observed during other kinds of seizures. Indeed, seizure-related MRI abnormalities mainly involve the cortical grey matter, while NKH-related seizures usually appear as reversible subcortical T2/fluid attenuation inversion recovery (FLAIR) hypointensity. This latter abnormality shows a good spatial correlation with the area of the ictal focus on electroencephalogram and could be associated with other more common post-ictal MRI changes (cortical grey matter T2/FLAIR hyperintensity, cortical or leptomeningeal enhancement). Although these abnormalities tend to be transient, a focal volume loss or gliosis can result on follow-up imaging. Our cases confirm T2/FLAIR subcortical hypointensity as a main neuroradiological hallmark of NKH-induced seizures.

Case Report: Abruptio placentae and epileptic seizure after occurrence of perinatal hyperglycaemia in woman with gestational diabetes mellitus and hypertriglyceridemia-induced acute pancreatitis

“…The cause of epileptic seizure in this patient was unknown. In previous reports, uncontrolled hyperglycemia can also cause seizure (21)(22)(23), which may be related to its brain damage (23)(24)(25)(26)(27). Most cases have been described in patients with non-ketotic hyperglycemia (NKH), which is a common complication of type 2 diabetes (28, 29).…”

Recurrent Facial Focal Seizures With Chronic Striatopathy and Caudate Atrophy—A Double Whammy in an Elderly Woman With Diabetes Mellitus

“…Typical neuroradiological feature of NKH-induced seizures is transient subcortical T2/fluid-attenuated inversion recovery hypointensity, while hyperintensity in cortical grey matter on T2/FLAIR, cortical and leptomeningeal enhancement are less frequent findings. 13,14 Interestingly, our patient's MRI did not have those findings; rather it revealed a space-occupying lesion in the right superior frontal cortex, which is known to include the cortex representing the motor homunculus corresponding to left side of the face. Possibly, space-occupying lesion in motor cortex acted as an inciting factor for seizures and NKH further lowered the seizures threshold.…”

A case of nonketotic hyperglycemia without movement anomalies: MRI findings

“…On magnetic resonance imaging, T2/FLAIR hypointensity in the subcortical posterior cerebral region is the most characteristic finding. 6 The most commonly reported MR imaging features of seizures associated with NKD are cortical hyperintensity and reversible subcortical hypointensity which may show restriction on diffusionweighted images. The mechanisms that may cause these findings are reported to be focal cytotoxic edema secondary to cortical focal ischemia or hyperviscosity caused by free radicals and their units.…”