Background: Evoked potentials (EP) visual (VEP) and auditory (BAEP) are used in diagnostics of demyelinating diseases, especially multiple sclerosis (MS). Elongation of the EP latencies and interlatencies has been found so far and sometimes change in the shape of the responses or decrease of their amplitudes has been registered as well.
Aim of the study: Characteristics of VEP and BAEP parameters in Polish children with MS.
Material and methods: Analysis included examination results of 10 patients with MS, at the age range from 13 to 17 years, 5 girls and 5 boys, hospitalized in the Department of Pediatric Neurology Chair of Pediatric and Adolescent Neurology Jagiellonian University Collegium Medicum in Krakow, in the years 2004-2010. Control group consisted of 10 children with similar age and sex distribution. VEP were registered during monocular stimulation with black and white checkerboard pattern reversal (pattern reversal VEP). Responses were registered from three active electrodes O1, O2 and Oz (according to the 10-20 International System of Electrode Placement). Latency of the maximal positive deflection P100, preceding N75 component, following N135 and N75/P100 amplitude were analysed. BAEP were evoked during alternating stimulation of the left and right ear, with the use of acoustic stimulus ("click") at 70 dB HL. The responses were registered from two receiving electrodes localized on the mastoid processes and from reference electrode Cz (according to the 10-20 International System of Electrode Placement). Latencies of I, II and V deflection and interlatencies: I-III, III-V, I-V were analyzed.
Results: As far as VEP are concerned, significant elongation of P100 latencies was revealed in children from examined group when compared with control. N75/P100 amplitude differences were not statistically significant in both groups. BAEP analysis revealed significant elongation of III and V wave latencies and III-V, I-V interlatencies.
Conclusions: Evoked potentials, visual and auditory are important paraclinical tests used in MS diagnostics in children. They are used in identification of clinically silent demyelinating foci.