Evaluation of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes with magnetic resonance imaging and proton magnetic resonance spectroscopy.
OBJECTIVE
To study the characteristics of spectra on proton magnetic resonance spectroscopy (1H-MRS) and its value in patients with mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS).


METHODS
Seven clinically diagnosed patients with MELAS underwent magnetic resonance imaging (MRI) and 1H-MRS examinations. The 1H-MRS techniques, characteristics of the spectra, and its correlation with the laboratory tests were analyzed.


RESULTS
Cerebral abnormalities were revealed in all 7 patients on conventional MR images, and most abnormal signals were observed in bilateral occipital, parietal, and temporal lobes. We found 4 cases with basal ganglia involvement, 2 cases with mild frontal lobe lesions, and 1 case with involvement of lateral cerebral peduncles and thalami. Additionally, 1 patient was involved with left insular lobe. Spectra from prominent lesions in brain parenchyma showed lactate doublet peak in 6 patients, 3 of whom were also noted lactate peak in ventricular cerebrospinal fluid (CSF).


CONCLUSIONS
1H-MRS may provide more direct information about the metabolism changes, which aids to affirm the diagnosis, and may replace the conventional invasive method of quantifying lactate in CSF.
Feng
Feng
F
Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730. ffeng@pumch.cn
You
Hui
H
Gao
Jing
J
Li
Xiao-Zhen
XZ
Meng
Chun-Ling
CL
Sun
Hong-Yi
HY
Jin
Zheng-Yu
ZY
Guo
Yu-Pu
YP
D000293:Adolescent; D000328:Adult; D001479:Basal Ganglia / Q000473:pathology / Q000503:physiopathology; D002540:Cerebral Cortex / Q000473:pathology* / Q000503:physiopathology; D002648:Child; D005260:Female; D006801:Humans; D019344:Lactic Acid / Q000378:metabolism; D017241:MELAS Syndrome / Q000175:diagnosis* / Q000503:physiopathology; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D010296:Parietal Lobe / Q000473:pathology / Q000503:physiopathology
D019344:Lactic Acid