Neuronal metabolic changes in the cortical region after subcortical infarction: a proton MR spectroscopy study.
OBJECTIVE
To investigate whether proton magnetic resonance spectroscopy ((1)H MRS) can detect neuronal metabolic changes in the cortical region in patients with cortical dysfunction after subcortical infarction.


METHODS
Fifteen patients with subcortical large (diameter>/=20 mm) infarcts were studied; nine patients with cortical dysfunction (group A), and six without (group B). Seven patients with lacunar infarction served as controls. Infarct volume was measured on T2 weighted images with an image analyser. (1)H MRS data were obtained in three regions; high signal intensity area on T2 weighted image, overlying cortex with a normal T2 MRI appearance, and contralateral homologous cortical region.


RESULTS
Infarct volume was not different between groups A and B. N-acetylaspartate (NAA)/creatine+phosphocreatine (Cr) ratios in the cortical region overlying subcortical infarcts in group A were significantly lower than those in group B and the control group (p=0.002). The NAA/Cr ratios in the overlying cortex were significantly lower than those in the contralateral normal cortex in group A on the initial (p=0. 015) and follow up (p=0.028) (1)H MRS, but these differences were not found in group B and the control group.


CONCLUSIONS
The results support the idea that the cerebral cortex is a responsible location for cortical dysfunction after subcortical infarctions. (1)H MRS can be used as a sensitive method for the detection of a neuronal metabolic damage, which is not demonstrated by conventional MRI.
Kang
D W
DW
Department of Neurology, College of Medicine, Seoul National University, 28 Yongon-dong, Chongno-gu, Seoul 110-744, Korea.
Roh
J K
JK
Lee
Y S
YS
Song
I C
IC
Yoon
B W
BW
Chang
K H
KH
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D002533:Cerebral Angiography; D002540:Cerebral Cortex / Q000098:blood supply / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology; D002544:Cerebral Infarction / Q000175:diagnosis / Q000378:metabolism*; D003401:Creatine / Q000378:metabolism; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000378:metabolism*; D010725:Phosphocreatine / Q000378:metabolism; D011446:Prospective Studies; D015899:Tomography, Emission-Computed, Single-Photon
D010725:Phosphocreatine; D001224:Aspartic Acid; C000179:N-acetylaspartate; D003401:Creatine