Visually evoked blood flow responses and vasoneuronal coupling in partial epilepsy.
OBJECTIVE
Increased metabolic demand is coupled with increased regional blood flow. The decreased vasoreactivity in epileptic patients however, prompts an impact of epileptic dysfunction on vasoneuronal coupling.


METHODS
Blood flow velocities during visual stimulation were monitored by TCD in both posterior cerebral arteries in 20 epileptic patients and 20 control persons, response-amplitudes (RA) and pulsatility indices (PI) were analyzed.


RESULTS
The RAs were significantly smaller in patients than in controls (28.4 +/- 5.7% vs 38.4 +/- 10.2%; P < 0.001). RAs were larger in the right side and these right-sided responses were significantly smaller in patients with right-sided vs left-sided epileptic foci (27.9 +/- 5.5% vs 36.1 +/- 4.5%; P < 0.005). The PI during stimulation was significantly larger in patients than in controls (0.92 +/- 0.11 vs 0.74 +/- 0.15; P < 0.001).


CONCLUSIONS
Our data suggest an impaired vasoneuronal coupling in focal epilepsy, and support the view that the right hemisphere might be more important for color processing.
National Stroke Centre, Hüvösvölgyi út 116. 1021 Budapest, Hungary. panczel@opni.hu
Gyula
G
Panczel
Bernd
B
Pohlmann-Eden
D000293:Adolescent; D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology*; D016022:Case-Control Studies; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004828:Epilepsies, Partial / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation; D020769:Posterior Cerebral Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*; D017585:Ultrasonography, Doppler, Transcranial