[MS2-2B-2] Clinical and EEG characteristics of children with atypical absence seizures
[Objective] To investigate clinical and EEG characteristics, therapeutic response and prognosis of children with atypical absence seizures. [Methods] The clinical features and EEG data of 43 children in our hospital from 2010 to 2016 with atypical absence seizures were analysed, therapeutic response and prognosis were followed up. [Results] Seizure onset occurred at the age from 1.8 years to 10.3 years. All children had atypical absence seizures during awakening or early drowsiness. Forty-two of 43 cases had other seizure types including tonic, myoclonus, atonic, generalized tonic-clonic and focal motor seizures. Lennox-Gastaut syndrome was diagnosed in 33 of 43 cases, Doose syndrome in 3 patients, continuous spike and waves during sleep and electrical status (CSWS) in 3 patients, Dravet syndrome in 2 patients, Landau Kleffner syndrome in 2 patients and Angelman syndrome in 1 patient. Forty patients developed psychological abnormalities or motor regression. Development was normal in 27 patients, slowed or regressed after seizure onset. Thirteen cases had developmental delay before disease onset. EEG features were background slowing and diffuse slow and spikes-waves of 1.5-2.8 Hz. Eighteen patients received pulsed methylprednisolone treatment, 5 of them got seizure control, 6 had decreased seizure frequency, 3 with no effect and 4 replased after treatment stopped. Seizures were controlled in six patients with valproate treatment, decreased in 11 patients. Eighteen cases were refractory to antiepileptic therapy and with obvious mental and motor regression. [Conclusions] Atypical absence seizures had a high incidence of motor regression and cognitive impairment. Methylprednisolone and AEDs might reduce seizure frequencies, but had little effect on psychological and motor regression.