Reduced /V-acetylaspartate concentration in temporal lobe epilepsy by quantitative ¹H MRS in vivo

Abstract

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