Clinical characteristics and electroencephalographic findings of first seizure episode in children

Introduction: Eyewitness and review of recorded video help in identifying seizure semiology in children. Electroencephalography (EEG) further helps to establish the diagnosis, ascertain the site of seizure origin, and to classify the epilepsy. Objectives: To study the clinical seizure types and associated EEG findings. Method: Children aged one month to 18 years with first seizure were enrolled prospectively. The detailed history, seizure type, examination findings and EEG characteristics, including wave pattern, spike-wave complexes, background, rhythm and epileptiform discharges, were studied. Results: Among 475 children with seizures; generalized seizures constituted 237 (49.9%), focal seizures 131 (27.6%), generalized status 31 (6.5%), focal status 6 (1.3%), epileptic encephalopathy 28 (5.9%) and epileptic syndromes 7 (1.5%). Seizures of generalized tonic-clonic type were observed in 134 (28.2%), absence in 21 (4.4%), atonic in 9 (1.8%) and myoclonic in 42 (8.8%). Focal seizures (FS) with impaired awareness (IAW), FS with awareness (AW) and bilateral tonic-clonic were 37 (7.8%), 30 (6.3%) and 58 (12.2%) respectively. EEG was abnormal in 394 (82.9%) children; 121 (30.7%) had epileptiform sharp/spike waves, 89 (22.5%) had slow waves, 47 (11.9%) had tri-phasic waves, 70 (17.7%) had poly-spike complexes, 63 (15.9%) had an abnormal background with slow-wave activity and 3 (0.7%) had hypsarrhythmia. All atonic and myoclonic seizures, generalized status, epileptic syndromes and 71.4% of absence seizures had associated generalized epileptic abnormalities on EEG. Percentage of children having associated EEG abnormalities was higher among focal seizures (74.8%) than generalized seizures (60.3%). Conclusions: EEG evaluation provided additional information in a large number of children with seizures. Focal seizures had higher associated EEG changes than generalized seizures.