REDUCED N-ACETYLASPARTATE CONCENTRATION IN TEMPORAL-LOBE EPILEPSY BY QUANTITATIVE (1)HMRS IN-VIVO

WE used proton magnetic resonance spectroscopy (H-1 MRS) to determine concentrations of N-acetylaspartate (NAA), creatine and choline in viv o (63 MHz) and in vitro (400 MHz) in seven patients undergoing surgica l treatment of intractable temporal lobe epilepsy (TLE). Nine healthy volunteers were used as controls for in vivo MRS. NAA concentrations i n vivo on the ipsilateral and contralateral sides were 6.5 +/- 1.3 (s. d.) and 7.9 (+/- 2.1) mmol l(-1), respectively and 8.6(+/- 0.8) mmol l (-1) in the volunteers. NAA concentration in vitro was 3.2 (+/- 0.9) m u mol gl wet weight (ww) and the corresponding concentration from the macroscopically intact brain tissue was 4.7 (+/- 1.0) mu mol g(-1) ww. Thus, in vivo quantitative H-1 MRS identified the side of seizure foc us in patients with temporal lobe epilepsy.