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Global Translational Medicine Deep learning by NMR-biochemical

blood flow, and impaired axonal functions are associated Mental State Examination (MMSE), APOE4, age, and sex.
with concussion and neuronal depolarization. H-MRS, or Low NAA/MI indicated low cognitive capacity in Aβ+
1
MRS, measures brain metabolites and physiologic changes patients with a high NAA/MI baseline. The longitudinal
after sport-related concussions. MRS-visible neurochemicals changes in mI/Cr and NAA/mI ratios classified the amyloid
monitor the altered neurophysiology and recovery of post- pathology types due to dementia [104] . In Aβ+ individuals,
concussive symptoms or injury returning to normative NAA/mI ratio predicts a declining rate of cognition in
levels in adult athletes . The author suggests that large the future. Now, a PET scan indicates the amyloid and tau
[97]
cross-sectional, prospective, and longitudinal studies will deposition to screen dementia and monitors the disease
establish the high sensitivity and prognostic value of MRS progression to evaluate molecular pathology in vivo using
in concussion. The American Medical Society for Sports MRS/PET in a clinical setting. The author suggests using
Medicine advocated the use of MRS in concussion in sports multimodal large-scale hybrid MRS-PET clinical trials to
as a research tool, not a management tool . measure metabolites and early β-amyloid and tau protein
[98]
The “Current Lyme disease” and “Nervous system Lyme changes in a single MRI+MRS session in Alzheimer’s disease
disease” guidelines mentioned the MRS as a diagnostic and shows the increased MI/Cr ratio with longitudinal
tool, not as a management tool . decline in NAA/mI ratio to track pre-dementia Alzheimer’s
[99]
disease progression in clinical trials.
The MRS studies showed high specificity and sensitivity
in children at short TE-chemical shift imaging of brain 6.4. Radiation encephalopathy
tumors [100] . The proton MRS measured the varied metabolite
The American College of Radiology’s Appropriateness concentrations of NAA/tCr ratio, Cho/Cho ratio, NAA,
Criteria of dementia and movement disorders favor the use Cho, and Cr in healthy control and post-radiotherapy
of fMRI and MRS in neurodegenerative disorders but not encephalopathy subjects. MRS evaluation is feasible to
for routine clinical practice [101] . Moreover, positron emission evaluate radiation therapy-induced encephalopathy in
tomography (PET), single-photon emission computerized nasopharyngeal carcinoma. The author suggests precise
tomography (SPECT), fMRI, DTI, and MRS may visualize subgroup analysis includes variables such as disease stage,
head trauma injury occult in children by standard imaging age, and sex [105] .
but are insufficient in routine clinical use. In young children
with attention-deficit/hyperactivity disorder (ADHD), 6.5. Theranosis of hepatic encephalopathy
autism spectrum disorders, emotional dysregulation, and MRSI visualized the altered imaging features showing
schizophrenia, H-MRS showed increased glutamine/ stratification, the severity of the hepatic encephalopathy
1
glutamate, related metabolites in the anterior cingulate in non-hepatic encephalopathy (HE) cirrhosis, minimal
cortex (ACC), and other regions. In major depression, HE, and overt HE patients by monitoring high glutamine/
bipolar disorders, and obsessive-compulsive disorder glutamate ratio, high choline, and high MI peaks in parietal
children, H-MRS showed low glutamine/glutamate. lobe by Metafor v3.4.1 software analysis in brain regions.
1
Limited evidence showed a normal GLx level after treatment These MRI+MRS features showed a correlation with high
of bipolar disorder and ADHD diseases to indicate the homogeneity and HE grade in all brain regions. However,
mechanism of glutamate dysregulation in these disorders [102] . evaluation can be biased by HE assessment cutoff, sample
6.3. Amyloid pathology in Alzheimer’s disease size, the method used, and geographic variation. In
parallel, overt HE severity and classification vary by West
1 H-MRS showed low NAA and low NAA/Cr ratio in Haven grades [106] .
posterior cingulate and bilateral left/right hippocampus
regions and high MI/Cr ratio in posterior cingulate and 6.6. Evaluation of liver steatosis in liver donors
gray matter in Alzheimer’s disease patients [103] . The author A meta‑analysis of hepatosteatosis using MRI+MRS in
suggests that NAA/Cr ratio, NAA, and MI are indicators of living liver donors showed high specificity and sensitivity
brain dysfunction, while MI/NAA and Cho/Cr ratios are of hepatosteatosis to avoid liver biopsy [107] . However, the
diagnostic indicators in Alzheimer’s disease subjects. use of MRS had several drawbacks: (i) moderate inter-
The amyloid pathology and proton MRS metabolites study clinical or statistical heterogeneity due to diagnostic
in non-dementia individuals show cognitive decline as threshold variability study methodology; (ii) MRI
changes +2.9%/year of MI/tCr ratio and −3.6%/year of and MRS suffer from selection and recall biases with
NAA/MI ratio in mild cognitive impairment β-amyloid higher sensitivity and specificity or may over-estimate
(Aβ+) patients; −0.05%/y mI/Cr and +1.2/y NAA/mI ratio in retrospective studies; and (iii) sample size, sex ratio,
in Aβ- patients, and the changes were associated with Mini- and mean age factors need meta-regression with these

Volume 2 Issue 3 (2023) 18 https://doi.org/10.36922/gtm.337