Evaluation of long-term neurocognitive functions in patients with epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS)/epileptic encephalopathy with spike-and-wave activation in sleep (EE-SWAS).

OBJECTIVES: Epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS) or the newly named Epileptic encephalopathy with spike-and-wave activation in sleep (EE-SWAS) is a syndrome in which epileptiform abnormalities are associated with the progressive impairment of cognitive functions. This study aimed to evaluate the neurocognitive executive functions of patients at later ages and determine the long-term prognosis of the condition, as well as the factors affecting this. METHODS: This is a hospital-based cross-sectional study of 17 patients with a diagnosis of CSWS, and a minimum age of 7.5 years. The Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) was used for neurocognitive assessment. The use of immunotherapy (intravenous immunoglobulin and/or steroid for at least 6 months) at the time of initial diagnosis, baseline activity and spike wave index (SWI) of the last wake and sleep EEG, cranial MRI findings, active epileptic seizures since the last examination, and WISC-IV parameters were statistically compared. The results of patients with genetic etiology determined by the whole exome sequencing (WES) method are also reported. RESULTS: A total of 17 patients were included in the study, with a mean age of 10.30 ± 3.15 years (range from 7.9 to 15.8 years). The mean full scale IQ score of the subjects was 61.41 ± 17.81 (range 39-91), classified as follows: 5.9% (n = 1), average; 23.5% (n = 4), low average; 5.9% (n = 1), very low; 35.3% (n = 6), extremely low (upper range); 29.4% (n = 5), extremely low (lower range) intelligence. Among the four domains of WISC-IV, the most affected index was the Working Memory Index (WMI). EEG parameters, cranial MRI findings and treatment with immunotherapy did not have a significant effect on neurocognitive outcomes. Thirteen patients (76%) were evaluated with WES for a genetic etiology. Pathogenic variants in 5 different genes (GRIN2A, SLC12A5, SCN1A, SCN8A, ADGRV1) associated with epilepsy were detected in 5/13 patients (38%). CONCLUSION: These results indicated that neurocognition is highly affected in the long term in CSWS.

Neurodevelopmental Findings and Epilepsy in Malformations of Cortical Development.

AIM: The purpose of this study is to classify the malformations of cortical development in children according to the embryological formation, localization, and neurodevelopmental findings. Seizure/epilepsy and electrophysiological findings have also been compared. MATERIAL AND METHODS: Seventy-five children (age: 1 month-16.5 years; 56% male) followed with the diagnosis of malformation of cortical development, in Marmara University Pendik Research and Educational Hospital Department of Pediatric Neurology, were included in the study. Their epilepsy characteristics, electroencephalogram (EEG) findings, and prognosis were reported. Neurodevelopmental characteristics were evaluated by the Bayley Scales of Infant and Toddler Development (Bayley-III) for the ages of 0-42 months (n = 30); the Denver Developmental Screening Test-II (DDST-II) for ages 42 months-6 years (n = 11); and the Wechsler Intelligence Scales for Children (WISC-R), used for children 6 years and older (n = 34). RESULTS: The patients were classified as 44% premigrational (14.6% microcephaly, 24% tuberous sclerosis, 2.7% focal cortical dysplasia, 1.3% hemimegalencephaly, and 1.3% diffuse cortical dysgenesis); 17.3% migrational (14.6% lissencephaly, 2.7% heterotopia); and 38.6% postmigrational (14.6% schizencephaly, 24% polymicrogyria) developmentally. According to involved area, the classification was 34.7% hemispheric/multilobar, 33.3% diffuse, and 32% focal. Seventy-five percent of the patients had a history of epilepsy, and 92% were resistant to treatment. The seizures started before the age of 12 months in diffuse malformations, and epileptic encephalopathy was more common in microcephaly with a rate of 80% and lissencephaly with a rate of 54.5% in the first EEGs. Ninety-five percent of patients had at least one level of neurodevelopmental delay detected by DDST/Bayley-III; this was more common in patients with accompanying epilepsy (P < .05). As seen more commonly in patients with diffuse pathologies and intractable frequent seizures, mental retardation was detected by WISC-R in 64.5% of patients (P < .05). CONCLUSION: In cases with cortical developmental malformation, epilepsy/EEG features and neurodevelopmental prognosis can be predicted depending on the developmental process and type and extent of involvement. Patients should be followed up closely with EEG.