T. Hashimoto et al., REDUCED N-ACETYLASPARTATE IN THE BRAIN OBSERVED ON IN-VIVO PROTON MAGNETIC-RESONANCE SPECTROSCOPY IN PATIENTS WITH MENTAL-RETARDATION, Pediatric neurology, 13(3), 1995, pp. 205-208
Volume-selective proton magnetic resonance spectroscopy (H-1-MRS) of t
he brain was performed with a 1.5T magnet in 28 patients with unclassi
fied mental retardation (MR) and in 25 age-matched healthy children, P
eaks of N-acetylaspartate (NAA), choline (Cho), and creatine (Cr), but
not of lactate, were observed in both groups on H-1-MRS. In all our s
ubjects of this age range, H-1-MRS revealed an increase with advancing
age in the ratio of NAA/Cho (P =.0031), but no developmental change i
n the NAA/Cr and Cho/Cr ratios. The NAA/Cho ratio was lower in patient
s with MR than in controls (P =.0016). The NAA/Cr ratio tended to be l
ower in the MR group, and the Cho/Cr ratio did not differ between pati
ents with MR and controls, These results suggest that in patients with
MR, NAA decreases and a disorder and/or dysfunction of neurons in the
brain exists.