Intermittent Rhythmic Delta Activity(IRDA) in Children / 대한소아신경학회지

ABSTRACT

BACKGROUND: Intermittent rhythmic delta activity (IRDA) is classified as a nonspecific abnormal EEG pattern. IRDA is clinically associated with alteration of consciousness, hydrocephalus, cerebral edema, deep midline lesions, subcortical lesions, and tumors of the posterior fossa and the third ventricle. Frontal IRDA(FIRDA) is usually seen in patients over age 15 years, whereas occipital IRDA(OIRDA) occurs mainly in children. We have investigated the clinical feature and significance of IRDA in children. SUBJECTS AND METHODS: We retrospectively reviewed the medical records of 36 children with IRDA of EEG concerning diagnosis, neurologic examination, classification of epilepsy, and CT & MRI findings. RESULTS: 1) The location of the IRDA was frontal(FIRDA) in 11 of 36(30.5%), occipital(OIRDA) in 20 of 36(55.6%) and mixed in 5 of 36(13.9%) patients. 2) Thirty of 36(83.3%) have epilepsy (including 1 each with MELAS and tuberous sclerosis), 4 of 36(11.1%) have migraine and 2 of 36(11.1%) patients have meningitis. 3) Sixteen of 30(53.3%) have partial or partial with secondary generalized seizure, 10 of 30(33.3%) have generalized seizure and 4 of 30(13.3%) patients with epilepsy have absence seizure. 4) Neuroimaging studies (CT or MRI scan) were performed in 27 cases. Among 27 cases of studies, 6 cases(22.2%) were abnormal including; two cases of infections, and each case of infarction, venous angioma, arachnoid cyst, cortical atrophy, and tuberous sclerosis, respectively. CONCLUSIONS: IRDA may be considered an epileptiform pattern in childhood and FIRDA is frequently seen in children than previous reports.