Thalamic dysfunction in juvenile myoclonic epilepsy: a proton MRS study.
OBJECTIVE
To investigate neuronal dysfunction in the thalami of patients with juvenile myoclonic epilepsy (JME) by using proton magnetic resonance spectroscopy (MRS).


METHODS
We performed single-voxel proton MRS over the right and the left thalami of 10 consecutive patients (five women) with JME (mean age, 31.6 years) and 10 age-matched healthy volunteers (five men). All patients had seizure onset in late childhood-teenage, normal neurologic examination, typical EEG of JME, and normal high-resolution MR imaging (MRI). We determined ratios of N-acetylaspartate (NAA) over creatine-phosphocreatine (Cr). Values <2 standard deviations from controls were considered abnormal. We performed analysis of variance to evaluate group differences.


RESULTS
Group analysis showed that thalami NAA/Cr ratios were significantly decreased in JME patients (left side, 1.58 +/- 0.26; right side, 1.5 +/- 0.15) as compared with controls (left side, 1.98 +/- 0.18; right side, 1.88 +/- 0.15; p = 0.001 and p = 0.007, respectively). Individual analysis showed that nine of the 10 patients had abnormal NAA/Cr in at least one of the thalami.


CONCLUSIONS
This study shows evidence of neuronal dysfunction in the thalami of patients with JME, which may have relevance for the mechanisms of seizure generation in this form of generalized epilepsy.
Mory
Susana B
SB
Department of Neurology, University of Campinas-UNICAMP, Campinas, SP, Brazil.
Li
Li M
LM
Guerreiro
Carlos A M
CA
Cendes
Fernando
F
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D003401:Creatine / Q000378:metabolism; D004292:Dominance, Cerebral / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D020190:Myoclonic Epilepsy, Juvenile / Q000503:physiopathology*; D010725:Phosphocreatine / Q000378:metabolism; D012016:Reference Values; D013786:Thalamic Diseases / Q000175:diagnosis / Q000503:physiopathology*; D013788:Thalamus / Q000503:physiopathology
D010725:Phosphocreatine; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine