The Study Of Visual-Auditory Synchrony Evoked Potential In Normal And Febrile Convulsion Infants

Objective To get dates of visual-auditory synchrony evoked potentials in normal and febrile convulsion infants. Compare these dates to their auditory brainstem responses(ABRs) and flash visual evoked potentials(FVEPs) alone. To find the characteristics visual-auditory synchrony evoked potential, and to discuss the influences of visual -auditory pathway mutually and the prognosis of FC. To prove the feasibility of visual-auditory synchrony evoked potential in FC, and to provide a powerful electro-physiology method for early detection and early diagnosis of visual & auditory impairment in infants.Methods Performed tests of visual-auditory synchrony evoked potential, ABR and FVEP alone to 44 normal infants, which were random selected, aged from 6-month to 3-year-old. Compare their visual-auditory synchrony evoked potentials to ABRs and FVEPs alone separately. According to The suggestion about the diagnosis and therapy of febrile convulsion, provided in children neurology academic meeting of china, 30 cases of FC at the same age received the same procedure within 24 hours of FC and one-week after the temperature came to normal. Latencies of wave I, III ,and V ,and inter-wave latencies of wave I - III, III - V and I - V of ABR latencies of wave Nl, PI, N2 of FVEP were recorded .Results l.ABR and FVEP norms were gotten in infants aged 6-month to 3-year-old. The latencies of their waves were tending to decrease as the age increased. The waves developed maturity gradually at 1.5-year-old for ABR and l~2-year-old for FVEP. 2. Visual-auditory synchrony evoked potential norms were gotten ininfants aged 6-month to 3-year-old. The latencies of their waves were tending to decrease as the age increased also. After comparing the visual-auditory synchrony evoked potential with ABR and FVEP alone, FVEP was fund to have significant influence on the wave latency of ABR (p<0.01), none significant influence on the inter-wave latency of ABR (p>0.05). ABR showed significance influence on wave Nl and N2 of FVEP (p<0.05) in infants aged 6-month to 1-year-old. 3. ABR and FVEP dates were gotten in FC infants aged 6-month to 3-year-old. Compared ABR and FVEP tests within 24- hour of FC to one-week after the temperature came to normal, there was no tendency of wave latency decreased as the age increased. The FC group of 3-year-old, showed longer latencies of ABR and FVEP than the other. One-week after the temperature came to normal, inter-wave latencies of I -III and III - V in 2-year-old group and inter-wave latencies of I -IIIand inter-wave latencies of I -III in 3-year-old group were make differences. FVEP latencies of Nl changed in 6-month to 1-year-old group at one-week later tests.4. Dates of visual-auditory synchrony evoked potentials were gotten in FC infants aged 6-month to 3-year-old. There was no tendency showed that wave latency decreased as the age increased. The latencies of ABR and FVEP in visual-auditory synchrony evoked potentials were longer than the other group in FC infants of 2~3-year-old. One-week after the temperature came to normal, the FVEP latency of wave N2 in visual-auditory synchrony evoked potentials showed some changes.Conclusion The latency of ABR and FVEP alone was tending to decrease as the age increased in infants from 6-month to 3-year-old. There was no difference between sex and different ear. Visual and auditory system showed some characters of adult in the stage of infant. ABR and FVEP norms provided clinical reference for early diagnosis of visual&auditory impairment in infants aged 6-month to 3-year-old. In the testing of visual-auditory synchrony wave I ,111 ,V of ABR and wave N1,P1,N2 of FVEP became more recognizable and well- differentiation. Visual-auditory synchrony evoked potential also increased the efficiency of the test. There might be some neurons in central nervous system transfer massages betweenvisual and auditory pathway. FVEP played an dominant role in visual-auditory synchrony evoked potential testing and influenced the latency of ABR significantly. To FC infants, the sd of ABR and FVEP in visual-auditory synchrony evoked potential was smaller than that of in ABR and FVEP alone, and the abnormal rate was obviously higher than that of in ABR and FVEP alone. This study showed us that visual-auditory synchrony evoked potential testing was a new electro-physiology method, which would provide powerful suggestion to test visual & auditory function in infants.