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). CONCLUSION: 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.
