Purpose: Epilepsy is one of the most common neurological disorders in both adults and children. After detailed history-taking, electroencephalography (EEG) is the most important investigation in the evaluation of epilepsy patients. Polyspikes, defined as a sequence of two or more spikes, are among the findings that can be seen on EEGs of epilepsy patients, but the literature on their significance in focal epilepsy patients is scarce. Therefore, in the current study, we investigated the significance of polyspikes on EEG in childhood focal epilepsy. Methods: A retrospective analysis was conducted of data from children who were diagnosed with focal epilepsy and received anti-seizure medications at Pusan National University Children’s Hospital. Results: Among the 1,125 children included in this study, 468 (41.6%) showed interictal polyspikes on their EEGs. In the multivariate analysis, only the presence of brain magnetic resonance imaging (MRI) abnormalities was significantly associated with the presence of interictal polyspikes on EEGs. Among patients with brain MRI abnormalities, localized polyspikes were significantly associated with focal cortical dysplasia, while multifocal polyspikes were significantly associated with perinatal insults (hypoxic-ischemic encephalopathy and destructive encephalomalacia). Conclusion: Focal epilepsy patients with interictal polyspikes were more likely to have a structural etiology. Furthermore, patients with localized polyspikes were more likely to have focal cortical dysplasia as the structural etiology, while patients with multifocal polyspikes were more likely to have perinatal insults as the structural etiology. This study demonstrates that focal polyspikes can be used as markers of the possible presence of a structural etiology in routine practice.

Purpose: The aim of this study was to evaluate the impact of the coronavirus disease 2019 (COVID-19) pandemic on children and adolescents with migraine. Methods: This longitudinal cohort study enrolled children and adolescents with migraine from the Department of Pediatric Neurology at our hospital from January 2017 to June 2021. Self-reported data from individual headache diaries were used. The patients were questioned about their headache frequency and intensity, stress, physical activity, changes in mood and sleep, and their school and home lives during the COVID-19 pandemic. The Pediatric Migraine Disability Assessment (Ped-MIDAS) scoring system was applied to assess headache-related disability. Results: In total, 325 pediatric migraine patients (mean age 12.8±5.6 years, 62.5% female) were included in this study. The average monthly frequency of migraine headaches was 2.17±1.32 and 4.62±3.29 before and during the COVID-19 pandemic (P<0.001), respectively. The Ped-MIDAS score was obtained for 207 patients both before and during the pandemic, and the total score slightly increased from 13.8 to 14.7 points (P=0.295). Sixty patients (18.5%) showed significantly worsening migraine headaches. Younger age (P=0.017), mood deterioration (P<0.001), sleep problems (P<0.001), increased acute medication use (P=0.010), and larger changes in the Ped-MIDAS score (P=0.002) were significantly associated with worsening headache in the logistic regression analysis. Conclusion: Headache attacks in children and adolescents with migraine were more frequent during the COVID-19 pandemic than before it. Worsening headaches could be independently attributed to younger age, mood deterioration, and poor sleep during the COVID-19 pandemic.

Purpose: A speech sound disorder (SSD) is defined as the presence of a problem with articulation and phonological processes in a child. This study analyzed the clinical characteristics of Korean patients with functional SSDs without any neuromuscular abnormalities. Methods: The medical records of patients aged 36 to 72 months old who were diagnosed with SSDs were retrospectively reviewed. SSD patients who scored less than 85 in the U-Tap test were divided into two groups according to their receptive language scores on the Preschool Receptive- Expressive Language Scale (PRES)/the Sequenced Language Scale for Infants (SELSI). Results: Sixty-seven percent of patients with language impairment (LI) who were diagnosed with an SSD initially visited the hospital for a delay in language development (n=18, 66.7%). Among children with only an SSD, 26.7% (n=8) of the patients recognized it as a language developmental problem. All SSD patients had substitution errors in the onset of initial syllables (SSD, SSD+LI: 100%; typical development [TD]: 37.5%). Of particular note, SSD children with LI had more omission errors (55.6%) than patients with SSD only (16.7%). SSD patients had higher error rates than TD children in all consonants except for the glottal element (P<0.01). The lower the U-Tap score of SSD patients, the lower their expressive language score (P<0.001). Conclusion: A high percentage of children with SSD initially visited the hospital for the treatment of language development delays. Articulation tests are essential for children who suffer from language delay. Furthermore, since incorrect articulation can lead to delays in expressive language development, early interventions should be considered.

Purpose: Paroxysmal motor events are common clinical symptoms in infants visiting pediatric neurology clinics. Due to the heterogeneous clinical symptoms and the difficulty of interpreting electroencephalography (EEG) in infants, differentiating paroxysmal motor events from epileptic events is challenging. This study aimed to investigate the risk factors for the diagnosis of epilepsy in infants and to develop a scoring system that predicts the risk of epilepsy. Methods: We retrospectively analyzed data from patients who presented with paroxysmal motor events in infancy between January 2008 and December 2009 at Asan Medical Center. Electronic medical records were reviewed for patients’ demographics, medical history, clinical characteristics associated with specific situations, and motor symptoms. Laboratory findings, EEG, and brain magnetic resonance imaging were also reviewed. Results: In total, 111 infants with paroxysmal motor events were enrolled. Non-epileptic paroxysmal motor events (NEPMs) were associated with specific situations (P<0.001). Patients with epilepsy were likely to have focal motor symptoms (P=0.08), a medical history of a neurologic disorder, and/or a family history of epilepsy (P<0.05). A risk scoring system was developed based on these risk factors; using this system, infants with 2 or more points could be diagnosed with epilepsy with 61.76% sensitivity and 88.31% specificity. Conclusion: Infants with paroxysmal motor events were more likely to be diagnosed with NEPMs than with epilepsy. An absence of specific situations for paroxysmal events, focal motor seizures, and a medical history of another illness were associated with the final diagnosis of epilepsy.

Purpose: Diagnosing Leigh syndrome (LS), a representative mitochondrial disease, remains challenging. Mitochondrial DNA (mtDNA)-associated LS, which is maternally inherited, has relatively well-known genetic variants. We evaluated the usefulness of brain magnetic resonance spectroscopy (MRS) for the initial diagnosis of mtDNA-associated LS using data from LS patients. Methods: The study involved LS patients who visited Gangnam Severance Hospital between 2006 and 2018. Based on patients’ clinical findings, genetic evaluations, brain magnetic resonance imaging, and brain MRS findings, 24 mtDNA-associated and 49 gene-negative LS patients were included in the current study. Lactate peaks and decreased N-acetyl aspartate (NAA) peaks in brain MRS were compared between both groups. Results: In total, 11 mtDNA mutation subtypes were detected. Our findings showed a higher proportion of brain MRS abnormalities in mtDNA-associated LS patients than in gene-negative LS patients, but no statistically significant differences were observed between the two groups (lactate peak, P=0.080; decreased NAA peak, P=0.115). Conclusion: Brain MRS is currently limited as an initial diagnostic test for mtDNA-associated LS. However, it may be a useful non-invasive test for the follow-up evaluation of mtDNA-associated LS treatment. Ultra-high-field MRS technology is expected in the future.

Purpose: The aim of this study was to investigate the effects of occipital nerve block (ONB) in pediatric patients with headache in the occipital region. Methods: Among 302 patients who visited our headache clinic during a 2-year period, we retrospectively reviewed the charts of 26 patients who complained of primary headache in the occipital region, and divided them into two groups according to the main treatment: ONB or oral drug treatment (ODT). Results: The mean age of the 26 patients was 11.7±3.2 years. No statistically significant differences were found between the ONB and ODT groups in age, sex, sites of pain, duration of having experienced symptoms, and the duration, frequency, and severity of episodes (P>0.05). There was no statistically significant difference in remission between the ONB and ODT groups. However, in the ONB group, the time taken to achieve remission was significantly shorter than in the ODT group (P<0.05). Additionally, in the ONB group, the duration of medication and the period of outpatient treatment were significantly shorter than in the ODT group (P<0.05). Conclusion: In this study, ONB reduced the time taken to achieve remission and shortened the period of treatment. Thus, ONB should be considered in pediatric patients with headache in the occipital region.