[Visual evoked potentials in children and school adolescents with migraine and tension-type headache. Clinical and neurophysiological correlations].

UNLABELLED: To differentiate clinically migraine, especially without aura, from tension-type headache (TTH), especially an episodic one, in patients in the developmental age may become a difficult task. The reason is the similarities of clinical symptoms in both types of headaches. The results of examinations published so far do not explain satisfactorily the pathomechanism and clinical symptoms of primary headaches. Therefore, it makes scientists apply more and more recent research methods to explain their pathophysiology. The aim of the study in children and adolescents with migraine and TTH was to evaluate the diagnostic values of visual evoked potentials (VEP). Clinical and neurophysiological correlations in primary headaches were also noted.

MATERIAL AND METHODS: 90 patients with migraine and 35 with TTH aged 8-18 participated in the study. The control group for neurophysiological examinations consisted of 66 healthy children and adolescents of the same age. VEPs were performed in the pain-free interval using 4-channel Multiliner (Toennies, Germany). The parameters for analysis were: latencies P100, N75, N145, amplitudes N75/P100, P100/N145 and interocular and interhemispheric differences.

RESULTS: Substantial prolongation of P100 and N145 latencies and reduction of N75/P100, P100/N145 amplitudes were recorded in one hemisphere only in patients with migraine. Correlations between VEP and age, duration of the disease and the frequency of migraine attacks were found. Presence and type of existing aura did not change values of recorded parameters in VEP CONCLUSIONS: The changes in VEP parameters were observed only in patients with migraine. The statistically significant interhemispheric differences without interocular changes point to their unilateral localization of the neuronal changes in visual pathway. The positive clinical and neuropsychological correlations obtained in migraine may be related to the vascular theory of migraine.