Effects of vigabatrin on brain GABA+/Cr signals in focus-distant and focus-near brain regions monitored by 1H-NMR spectroscopy.
The new antiepileptic drug vigabatrin (VGB) increases gamma-aminobutyric acid (GABA) in the brain. We compared GABA+/Cr signals measured focus-near and focus-distant and correlated it with the degree of response to VGB. Brain GABA+/Cr signals were measured in 17 epileptic patients in structurally normal appearing tissue by nuclear proton magnetic resonance (1H-NMR) spectroscopy using a special editing sequence for GABA. In 11 patients the measurements were done in brain areas distant to focus and in six near to focus. Full-responders (seizure reduction of >or=50% at the end of the treatment phase) and partial-responders (seizure reduction of >or=50% at the end of the first month of treatment but <or=50% at end of treatment) had lower GABA+/Cr signals in the hemisphere with the epileptogenic focus and increases of the GABA+/Cr signals with VGB. Non-responders (seizure reduction of <or=50%) had no side difference in the GABA+/Cr signals before treatment and no increase during treatment. These observations were made in structurally normal appearing tissue near to the focus and distant to the focus. A side difference in brain GABA+/Cr signal between the epileptogenic and non-epileptogenic hemisphere before VGB treatment correlates with an improved seizure control under VGB treatment regardless whether the measurement is done focus-near or focus-distant.
Mueller
S G
SG
Department of Neurology, University Hospital, Frauenklinikstr 26, CH-8091 Zurich.
Weber
O M
OM
Duc
C O
CO
Meier
D
D
Russ
W
W
Boesiger
P
P
Wieser
H G
HG
D000293:Adolescent; D000328:Adult; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002860:Chromium Radioisotopes; D017029:Epilepsy, Complex Partial / Q000188:drug therapy* / Q000378:metabolism; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods* / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D018709:Statistics, Nonparametric; D020888:Vigabatrin / Q000494:pharmacology* / Q000627:therapeutic use; D005680:gamma-Aminobutyric Acid / Q000032:analysis* / Q000378:metabolism
D002860:Chromium Radioisotopes; D005680:gamma-Aminobutyric Acid; D020888:Vigabatrin