[Assessment of cerebral blood flow after visual stimulation in children with a migraine and chronic tension-type headache--preliminary reports].

BACKGROUND

Transcranial Doppler enables dynamic assessment of cerebral blood flow and is particular important in migraine, associated with impaired vasoreactivity. Majority of studies revealed disturbed mechanisms of autoregulation in patients with migraine with aura in predominance. Visual aura and increased photosensitivity in migraine patients suggest disorders of visual pathway and visually evoked potentials (VEP) enable to detect even subclinical pathologic changes in its course.

AIM OF THE STUDY

Aim of the study was evaluation of cerebral blood flow in middle cerebral arteries in response to visual stimulation and analysis of VEP values in children with primary headaches.

MATERIAL AND METHODS

15 children were included, aged 8-18 years, hospitalized at Pediatric Neurology Department of Jagiellonian University in the first 5 months of year 2008 with headaches. Children with secondary headaches were excluded. 8 patients were with migraine with aura, 1 with migraine without aura, 3 with hemicrania epileptica and 3 with chronic tension-type headaches. Cerebral blood flow was measured in middle cerebral arteries during headache-free period with Transcranial Doppler Nicolet/EME Companion III. Evaluated parameters were: systolic velocity, end-diastolic velocity, mean velocity and indexies: pulsatility (Gosling's index) and resistive (Pourcelot's index). VEP were recorded during visual stimulation with black and white checkerboard pattern reversal with Keypoint/Medtronic-Dantec. Latencies N75, P100, N135 and amplitudes N75/P100, P100/N135 were examined.

RESULTS

Values of cerebral blood flow velocities increased over 10 cm/s in response to visual stimulation in 6 patients (2 with migraine with aura, 2 with hemicrania epileptica, 1 with migraine without aura, 1 with chronic tension-type headaches). In 5 of these patients amplitudes N75/PIOO and in 2 patients also P100/N135 over 20 mV were recorded. In 4 patients with migraine with aura with amplitudes N75/P100 or also P100/N135 over 20 mV, significant changes in cerebral blood flow were never observed.

CONCLUSIONS

Simultaneous recording of cerebrovascular response to visual stimulation and VEP revealed increase of cerebral blood flow velocity over 10 cml s in 6/15 patients and in 5 of them also amplitudes N75/ P100 or also P100/N145 over 20 mV were recorded. However, analysis of the results did not allow to identify characteristic changes for each type of headache. In order to establish the role of doppler examination in childhood migraine diagnostics further study in this area is needed.