A Retrospective Study Of 31 Cases With Photosensitive Epilepsy In Children

Objective:The electruphysiolugical and clinical feabures of children with photosensitive epilepsy(PSE)were retrospectively analyzed,and their antiepileptic drugs(AEDs)response were followed up.The results were compared with benign childhood epilepsy with centrotemporal spikes(BECTs)who were negative in intermittent photic stinulation(IPS)test,in order to deeply understand PSE in children.Methods:398 children with epilepsy diagnosed by video-EEG(VEEG)moaitoring and successfully cooperating to complete the IPS test were collected.The general features and EEG data of 31 children with IPS positive PSE were analyzed retrospectively.Among them,25 cases were followed up on the therapeutic outcome,and 6 cases were lost Meanwhile,there were 23 children with BECTs have completed IPS test,as a result,they all present negative response and taken as the control group.Among them,22 cases were followed up on the therapeutic outcome,and 1 case was lost.Results:(1)PSE accounted for 7.79%(31/398)of children with epilepsy during the same period.The male to female ratio was 1:3.43,the average onset age was 7.84±3.28 yrs,of which 20 cases(64.52%)were female children over 6 yrs,showing a female dominant tendency.In the same period,the male to female ratio of 23 cases with BECTs was 1.09:1,and the average onset age was 6.66±2.13 yrs.(2)EEG discharges were induced in the eye closure state in 83.87%(26/31)of the PSE children,which was signficantly hogher than that of eye-opened state(13/31,41.94%)and eye-closed state(11/31,35.48%)(All P<0.05).Electro-clinical seizures were led in the eye closure state in 35.48%(11/31)PSE cases,which was higher than that of eye-closed state(3/31,9.68%)(P<0.05).(3)The most sensitive frequency range of IPS test for the induction of EEG epileptic discharges or electro-clinical seizures was 10?20 Hz.(4)Elactro-chnical seizures were induced during IPS test in 13 cases(13/31,41.94%)of PSE children,the seizure types of whom included:myoclonic seizures(4/13,30.77%),absence seizures(3/13,23.08%),eyelid myoclonic seizures(2/13,15.38%),eyelid myoclonic seizures with or without absence(2/13,15.38%),absence with atonic seizures(1/13,7.69%)and focal seizure initdated from frontal region(1/13,7.69%).(5)Amnng the 13 children who were induced electro-clinical seizures during IPS test,EEG generalized discharges were induced in 12 cases(12/13,92.31%),only 1 case(1/13,7.69%)EEG presented localized discharge to generalized discharge.In the 18 cases whose IPS test induced only EEG epileptic discharge,there were 6 cases(6/18,33.33%)presented generalized discharges,6 cases(6/18,33.33%)started from localized discharges to generalized discharges,and the remaining 6 cases(6/18,33.33%)only induced localized discharges.(6)Among the 25 PSE cases who were successfully followed-up in AEDs treatment response,3 cases were not treated with AED s.In the 22 cases treated with AEDs,20 cases were given single drug,and 19 cases(19/20,95%)were effective,in addition,seizure free was obtained in 17 cases(17/20,85%),only 1 case was ineffective but did not receive combined therapy.2 cases of combined treatment with AEDs achieved complete control of seizures.The commonly used drugs for single or combined therapy are valproic acid(VPA)aad levetiracetam(LEV).In the 22 BECTs cases who were successfully followed-up,3 cases did not use AEDs.Among the 19 BECTs cases treated with AEDs,single drug was used in 14 cases,and seizure free was obtained in all of thern.In the 5 cases treated with combined AEDs,2 cases(2/5,40%)were effective,however,the seizures of them were not completely controlled.3 cases(3/5,60%)were ineffective aad seizures still frequently occurred.The commonly used drug for single or combined therapy are LEV,oxcarbazepine(OXC)and VPAin BECTs children.Conclusion:(1)The incidence of PSE was dominant in female older children,and the most sensitive frequency range of IPS test was 10?20Hz.The IPS test was all negative in BECTs children,and there wars no signfficant gender difference.(2)The EEG generalized discharges induced by IPS test was prone to electro-clinical seizures in PSE children.(3)In children with PSE,the highest inducing rate of EEG discharge induced by IPS was the eye closure state,the second was the eye-opened state,and the lowest was the eye-closed state.(4)The AEDs efficacy in PSE presents good response,and the commonly used drugs for single therapy are VPA and LEV.