A proton magnetic resonance spectroscopy study of focal epilepsy in humans.
Localized in vivo proton magnetic resonance spectra obtained from diseased areas in 2 patients with chronic localized encephalitis (Rasmussen's syndrome) showed reduced resonance intensities from N-acetyl compounds, suggesting focally decreased N-acetylaspartate concentrations. One of the patients had epilepsia partialis continua secondary to the encephalitis. In this patient, the spectra demonstrated a high lactate resonance intensity (not seen in the normal, contralateral hemisphere) corresponding to an estimated local concentration of about 7.5 mM. We speculate that the observed decrease in the N-acetyl compound resonance may be a biochemical correlate of the neuronal loss characteristic of this disease. The results establish that excessive accumulation of lactate can occur in the human brain as a result of seizure activity even in the absence of ischemia. Thus, bioenergetic compromise may be 1 predisposing factor to the death of excitable cells in the epileptogenic area.
Matthews
P M
PM
Montreal Neurological Institute and Hospital, PQ, Canada.
Andermann
F
F
Arnold
D L
DL
D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000032:analysis; D001921:Brain / Q000378:metabolism / Q000473:pathology; D002648:Child; D002908:Chronic Disease; D004660:Encephalitis / Q000378:metabolism / Q000473:pathology; D004828:Epilepsies, Partial / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D007773:Lactates / Q000032:analysis; D009682:Magnetic Resonance Spectroscopy; D008297:Male
D007773:Lactates; D001224:Aspartic Acid; C000179:N-acetylaspartate