Reduced brainN-acetyl-aspartate in frontal lobes suggests neuronal loss in patients with amyotrophic lateral sclerosis

Reduced NAA in motor and non‐motor brain regions in amyotrophic lateral sclerosis: a cross‐sectional and longitudinal study

“…Because most previous MRS studies of ALS examined regions of interest that were sufficiently distant from the skull to avoid interference from lipids, sampling of motor cortex was often limited. 5,[9][10][11][14][15][16][17][18][19][20][21][22] Using a Multiplanar 1 H MRSI technique to sample a larger region that includes the brain surface, reductions of the ratio NAA/ CrezCho have been observed in the region of the motor cortex and corticospinal tract. 7 A quantitative analysis of these data showed that decreased NAA was responsible for the ratio changes in the motor cortex and increased Cho for ratio changes in the corticospinal tract.…”

Early detection and longitudinal changes in amyotrophic lateral sclerosis by 1 H MRSI

“…Cre represents a combination of creatine and phosphocreatine, a putative marker of gliosis, 3,6 and Cho is thought to be a marker associated with membrane phospholipids. 7In most previous MRS studies of ALS,4,[8][9][10][11][12][13][14][15][16][17][18][19][20] sampling of metabolite signals from the motor cortex was limited, because measurements were restricted to a rectangular region within the brain that was sufficiently distant from the skull to avoid interferences with an intense signal from extracranial lipids. Furthermore, because the selected regions of interest were generally large, including unavoidably some white matter and nonmotor tissue, results from these studies may have been skewed to the extent that white matter and nonmotor regions contributed to the metabolite signal from the motor cortex.…”

Amyotrophic lateral sclerosis: Objective upper motor neuron markers

“…They found a more pronounced decrease in the NAA/creatine ratio in patients with definite UMN signs compared with patients with probable UMN signs [17]. Several other studies have confirmed this finding of decreased NAA in the motor cortex of ALS patients compared with healthy control patients, and the mean decrease was reported between 8% and 56% [14,15,[18][19][20][21][22][23].…”