Early thalamic lesions in patients with sleep-potentiated epileptiform activity

Department of Neurology, Children’s Hospital Boston, Harvard Medical School, Boston, MA, USA.
Neurology (Impact Factor: 8.29). 04/2012; 78(22):1721-7. DOI: 10.1212/WNL.0b013e3182582ff8
Source: PubMed


To compare the prevalence and type of early developmental lesions in patients with a clinical presentation consistent with electrical status epilepticus in sleep either with or without prominent sleep-potentiated epileptiform activity (PSPEA).
We performed a case-control study and enrolled patients with 1) clinical features consistent with electrical status epilepticus in sleep, 2) ≥1 brain MRI scan, and 3) ≥1 overnight EEG recording. We quantified epileptiform activity using spike percentage, the percentage of 1-second bins in the EEG tracing containing at least 1 spike. PSPEA was present when spike percentage during non-REM sleep was ≥50% than spike percentage during wakefulness.
One hundred patients with PSPEA (cases) and 47 patients without PSPEA (controls) met the inclusion criteria during a 14-year period. Both groups were comparable in terms of clinical and epidemiologic features. Early developmental lesions were more frequent in cases (48% vs 19.2%, p = 0.002). Thalamic lesions were more frequent in cases (14% vs 2.1%, p = 0.037). The main types of early developmental lesions found in cases were vascular lesions (14%), periventricular leukomalacia (9%), and malformation of cortical development (5%). Vascular lesions were the only type of early developmental lesions that were more frequent in cases (14% vs 0%, p = 0.005).
Patients with PSPEA have a higher frequency of early developmental lesions and thalamic lesions than a comparable population of patients without PSPEA. Vascular lesions were the type of early developmental lesions most related to PSPEA.

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    • "One of our symptomatic patients had a right anterior temporal arachnoid cyst which could be a coincidental finding. However the presence of convergent EEG findings emanating from the right centrotemporal area may suggest a causal relationship [16] [19]. The most commonly reported cortical malformation in the etiology of symptomatic ESES is polymicrogyria. "
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