Epilepsy with Eyelid Myoclonia (EEM) is a rare childhood-onset epilepsy syndrome. There is limited data about cognitive function and psychiatric comorbidities in patients with EEM. A database of 134 patients with EEM was reviewed for patients who underwent neuropsychological testing. Psychiatric comorbidities and psychometric test scores were identified. Group comparison was performed between those who underwent neuropsychological testing and those who did not. In addition, we evaluated whether clinical factors were associated with IQ score. Fourteen patients underwent neuropsychological testing (12 females, 85.7%), with a median age at testing of 17 (range 7-22). Median IQ was 79 (range 56-110); 7 patients had below average IQ. Other median results of neuropsychometric measures were: Verbal Comprehension Index 85.5 (range 66-116), Perceptual Reasoning Index or Visual Spatial Index 81.5 (range 67-100), Working Memory Index 77 (range 54-100), Processing Speed Index 84 (range 53-94), and Reading Standardized Scores 84 (range 64-126). Common psychiatric comorbidities were anxiety (n = 10), depression (n = 7), ADHD (n = 6), and autism (n = 2). Those who underwent neuropsychological testing had a younger age of epilepsy onset, longer follow-up at our institution, and were more likely to have myoclonic seizures or psychosis than those who did not undergo neuropsychological testing. No clinical factors were statistically associated with IQ score. EEM is associated with a wide range of cognitive abilities, with half of our patients having a below average IQ. Psychiatric comorbidities were common. Identifying cognitive impairment and psychiatric comorbidities is crucial to implement appropriate management strategies.

Epilepsy with eyelid myoclonia (EEM), with or without absence, also known as Jeavons Syndrome (JS), is a unique epileptic syndrome. This syndrome may be accompanied by other generalized seizures, such as generalized, tonic-clonic, myoclonic, and rarely atomic seizures. This study was conducted to determine the diversity of clinical and neurophysiological manifestations of JS in the pediatric population of Iran. This retrospective, cross-sectional study was conducted at the Children's Medical Center of Tehran, Iran, from 2017 to 2023. Two clinical neurophysiologists reviewed long-term video electroencephalographic (EEG) monitoring to confirm the diagnosis. Patients' demographic information was extracted from medical records or direct interviews based on clinical characteristics and history taking. Among 1530 patients admitted during the study period, 12 out of 17 previously diagnosed patients confirmed their diagnosis. Among the group of confirmed patients, seven were boys and five were girls. The average age of seizure onset was 3.4±1.7 years. Except for absence seizures, five out of 12 had no other types of seizures. Two patients showed generalized tonic-clonic events as associated seizures. One patient had astatic seizures, in the form of head drop, one patient had myoclonic seizures, and three patients had focal seizures without persistency in the EEG. Eleven of the 12 patients had focal electrographic findings during recording, with eight having focal epileptiform discharges during the interictal period. JS is an under-recognized epileptic syndrome requiring accurate diagnosis through identifying seizure types and EEG features. Although it is classified as a generalized epilepsy, focal seizures have been reported in a few case reports and were observed in three patients during the ictal period in our study. Additionally, focal electrographic findings were prevalent during the interictal period. Further research is needed to better understand the clinical and neurophysiological aspects of this syndrome.

Heterozygous DHDDS variants have been associated with intellectual disability and seizures, with or without movement disorders. We aimed to expand the known phenotypic spectrum of DHDDS-related disorders by elucidating the clinical characteristics of Japanese patients with recurrent DHDDS variants. Patients with pathogenic DHDDS variants were recruited from individuals diagnosed with developmental and epileptic encephalopathy or progressive myoclonus epilepsies who were treated at the Department of Child Neurology, National Hospital Organization Nishiniigata Chuo Hospital, or the Department of Pediatrics, Osaka Metropolitan University Graduate School of Medicine. DHDDS pathogenic variants were identified using exome sequencing. Medical records and neurophysiological data were retrospectively reviewed. Three de novo recurrent pathogenic DHDDS variants were identified in four patients: c.632G>A, p.(Arg211Gln) in two; c.614G>A, p.(Arg205Gln) in one; and c.110G>A, p.(Arg37His) in one. Three patients with p.(Arg211Gln) or p.(Arg37His) presented with severe intellectual disability and intractable generalized epilepsy, characterized by myoclonic, myoclonic-atonic, and atonic seizures. Eyelid myoclonia was the initial manifestation in infancy. One patient with p.(Arg205Gln) had a relatively mild course, with focal epilepsy and less severe intellectual disability. Myoclonus and tremor were present from infancy in two patients with p.(Arg211Gln) or p.(Arg37His), and from childhood in the patient with p.(Arg205Gln). One patient with p.(Arg211Gln) exhibited polymicrogyria in the right frontal lobe. Among the three patients with generalized epilepsy, fenfluramine effectively reduced myoclonic seizures in one, while total corpus callosotomy markedly reduced myoclonic-atonic or atonic seizures with falls in another. DHDDS-related disorders should be considered in patients with intellectual disability, epilepsy with early-onset eyelid myoclonia and myoclonic or myoclonic-atonic seizures, and movement disorders, including myoclonus and tremor, with slow progression. We identified polymicrogyria as a novel finding in DHDDS patients. For drug-resistant epilepsy in these patients, corpus callosotomy and fenfluramine may represent promising treatment options, with this report providing specific insights into their efficacy.

Epilepsy with eyelid myoclonia (EEM), previously known as Jeavons syndrome, is an under-recognized idiopathic generalized epilepsy characterized by eyelid myoclonia, often triggered by photic stimulation or eye closure. Despite its classification under absence epilepsies, the clinical and neurophysiological spectrum of EEM remains heterogeneous. A systematic review and meta-analysis were conducted following PRISMA guidelines. Databases including PubMed, Scopus, and Cochrane were searched from inception until January 16, 2025. Eligible studies reported clinical, electrophysiological, and treatment outcomes in patients with confirmed EEM. Pooled proportions and means were estimated using random-effects models. Twenty-eight studies encompassing 1,484 patients were analyzed. EEM predominantly affected females (69.35 %, 95 % CI: 65.53 %-72.93 %). The mean age at onset was 9.09 years (95 % CI: 8.02-10.16). Absence seizures were present in 55.61 % (95 % CI: 39.76 %-70.4 %), while generalized tonic-clonic seizures occurred in 52.65 % (95 % CI: 43.08 %-62.02 %). Photosensitivity was the most frequent trigger (75.91 %, 95 % CI: 60.11 %-86.82 %). Generalized spike-wave discharges were observed in 81.13 % (95 % CI: 70.91 %-88.35 %). Drug resistance was reported in 31.73 % (95 % CI: 17.36 %-50.67 %), with patients trialing a mean of 3.28 (95 % CI: 2.14-4.42) anti-epileptic drugs. Follow-up duration averaged 7.25 years (95 % CI: 5.67-8.82). EEM remains a distinct but clinically variable epilepsy syndrome. The high prevalence of photosensitivity and frequent misclassification highlight the need for improved diagnostic criteria. Despite treatment, seizure persistence is common, necessitating individualized therapy. Future research should explore genetic underpinnings and non-pharmacological interventions.