Relationship between cortex and pulvinar abnormalities on diffusion-weighted imaging in status epilepticus

Abstract

The aim of this study was to analyze the pattern of magnetic resonance diffusion-weighted imaging (DWI) findings in status epilepticus in terms of clinical characteristics. Participants comprised 106 patients with status epilepticus who were admitted to our hospital and underwent DWI. Forty-five patients (42.5 %) showed abnormal findings on DWI and were divided into two groups, comprising 26 patients (24.5 %) with cortex lesions alone and 19 patients (17.9 %) with cortex and pulvinar lesions in the same hemisphere. A long duration of status epilepticus (>120 min) tended to be more prevalent among patients with cortex and pulvinar lesions (57.9 %) than among patients with cortex lesions alone (30.8 %) by univariate and multivariate analyses. Todd's palsy tended to be more frequent in patients with abnormalities on DWI (24/45, 53.3 %) than in patients with normal DWI (21/61, 34.4 %). Six of the 26 patients with cortex lesions alone (23.1 %) had taken anti-epileptic drugs before the attack compared to none of the 19 patients with both cortex and pulvinar lesions. The trend toward a longer duration of status epilepticus in patients with both cortex and pulvinar lesions favors a spreading pattern of seizure discharge from cortex to pulvinar via cortico-pulvinar pathways, and anti-epileptic drugs might, to some extent, prevent spreading of seizure discharge from cortex to pulvinar. In addition, existence of high-intensity areas on DWI at the onset of epilepsy may be a predictive factor for the occurrence of Todd's palsy.

Neuroimaging alterations related to status epilepticus in an adult population: Definition of MRI findings and clinical‐EEG correlation

“…Because these MRI changes are supposedly caused by continuous or repetitive epileptic activity, a higher proportion of patients with PMAs can be | 125 expected if MRI is performed during the SE instead of after its cessation. 24,28 Nevertheless, it is still possible to find these alterations for some time after the end of SE; the duration could depend on two factors: patient characteristics (eg, age, comorbidities), or seizure characteristics (type and duration of ictal activity).…”

Brain magnetic resonance in status epilepticus: A focused review

“…Nakae et al presented 106 patients with DWI signal abnormalities in 42.5% of them; 24.5% presented with cortex lesions alone and 17.9% with both cortex and pulvinar ipsilateral lesions. They found that a long duration of SE (120 min) tended to be more prevalent in the group of both pulvinar and cortex lesions (57.9%), a trend that favors a spreading pattern of seizure discharge via cortico-pulvinar connections [16].…”

Neuroimaging of status epilepticus

“…In some cases, the high DWI signal is accompanied by high signal in ADC map and corresponding hyperintensities in T2‐weighted and fluid‐attenuated inversion recovery (FLAIR) sequences representing vasogenic instead of cytotoxic edema . Of interest, especially in focal seizures, coherent and reproducible patterns of MRI alteration can be found in the areas of the highest seizure activity (eg, neocortex or mesolimbic structures) as well as in remote areas (eg, the homolateral pulvinar nucleus of the thalamus, the contralateral cerebellum, the basal ganglia, and the claustrum) showing that during SE sustained ictal activities involve complex cortico‐subcortical networks …”