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Hyperpolarization techniques significantly enhance the sensitivity of magnetic resonance (MR) and thus present fascinating new directions for research and applications with in vivo MR imaging and spectroscopy (MRI/S). Hyperpolarized 13C MRI/S, in particular, enables real-time non-invasive assessment of metabolic processes and holds great promise for a diverse range of clinical applications spanning fields like oncology, neurology, and cardiology, with a potential for improving early diagnosis of disease, patient stratification, and therapy response assessment. Despite its potential, technical challenges remain for achieving clinical translation. This paper provides an overview of the discussions that took place at the international workshop "New Horizons in Hyperpolarized 13C MRI," in March 2023 at the Bavarian Academy of Sciences and Humanities, Munich, Germany. The workshop covered new developments, as well as future directions, in topics including polarization techniques (particularly focusing on parahydrogen-based methods), novel probes, considerations related to data acquisition and analysis, and emerging clinical applications in oncology and other fields.

Simple Summary: Advances in molecular techniques have significantly improved our understanding of glioblastoma in recent decades. Here, we describe the genetic mutations important in the pathogenesis, diagnosis, prognosis, and treatment of glioblastoma. We then describe novel diagnostic tools that allow for faster and less invasive diagnosis as well as monitoring of treatment response and disease recurrence. This summary will serve as a reference for the current state-of-the-art and future directions for glioblastoma treatment. Glioblastoma is the most common primary brain tumor in adult patients, and despite standard-of-care treatment, median survival has remained less than two years. Advances in our understanding of molecular mutations have led to changes in the diagnostic criteria of glioblastoma, with the WHO classification integrating important mutations into the grading system in 2021. We sought to review the basics of the important genetic mutations associated with glioblastoma, including known mechanisms and roles in disease pathogenesis/treatment. We also examined new advances in image processing as well as less invasive and noninvasive diagnostic tools that can aid in the diagnosis and surveillance of those undergoing treatment for glioblastoma. Our review is intended to serve as an overview of the current state-of-the-art in the diagnosis and management of glioblastoma. [ABSTRACT FROM AUTHOR]

Background: Emerging evidence suggests that fasting could play a key role in cancer treatment. Its metabolic effects on gliomas require further investigation. Purpose: To design a multi‐voxel 1H/31P MR‐spectroscopic imaging (MRSI) protocol for noninvasive metabolic monitoring of cerebral, fasting‐induced changes on an individual patient/tumor level, and to assess its technical reliability/reproducibility. Study Type: Prospective. Population: MRS phantom. Twenty‐two patients (mean age = 61, 6 female) with suspected WHO grade II‐IV glioma examined before and after 72‐hour‐fasting prior to biopsy/resection. Field Strength/Sequence: 3‐T, 1H decoupled 3D 31P MRSI, 2D 1H sLASER MRSI at an echo time of 144 msec, 2D 1H MRSI (as water reference), T1‐weighted, T1‐weighted contrast‐enhanced, T2‐weighted, and FLAIR. sLASER and PRESS sequences were used for phantom measurements. Assessment: Phantom measurements and spectral simulations were performed with various echo‐times for protocol optimization. In vivo spectral analyses were conducted using LCModel and AMARES, obtaining quality/fitting parameters (linewidth, signal‐to‐noise‐ratio, and uncertainty measures of fitting) and metabolite intensities. The volume of glioma sub‐regions was calculated and correlated with MRS findings. Ex‐vivo spectra of necrotic tumor tissues were obtained using high‐resolution magic‐angle spinning (HR‐MAS) technique. Statistical Tests: Wilcoxon signed‐rank test, Bland–Altman plots, and coefficient of variation were used for repeatability analysis of quality/fitting parameters and metabolite concentrations. Spearman ρ correlation for the concentration of ketone bodies with volumes of glioma sub‐regions was determined. A P‐value <0.05 was considered statistically significant. Results: 1H and 31P repeatability measures were highly consistent between the two sessions. β‐hydroxybutyrate and acetoacetate were detectable (fitting‐uncertainty <50%) in glioma sub‐regions of all patients who completed the 72‐hour‐fasting cycle. β‐hydroxybutyrate accumulation was significantly correlated with the necrotic/non‐enhancing tumor core volume (ρ = 0.81) and validated using ex‐vivo 1H HR‐MAS. Data Conclusion: We propose a comprehensive MRS protocol that may be used for monitoring cerebral, fasting‐induced changes in patients with glioma. Evidence Level: 1 Technical Efficacy: Stage 4 [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study was to propose a novel preprocessing approach to simultaneously correct for the frequency and phase drifts in MRS data using cross‐correlation technique. Methods: The performance of the proposed method was first investigated at different SNR levels using simulation. Random frequency and phase offsets were added to a previously acquired STEAM human data at 7 T, simulating two different noise levels with and without baseline artifacts. Alongside the proposed spectral cross‐correlation (SC) method, three other simultaneous alignment approaches were evaluated. Validation was performed on human brain data at 3 T and mouse brain data at 16.4 T. Results: The results showed that the SC technique effectively corrects for both small and large frequency and phase drifts, even at low SNR levels. Furthermore, the mean square measurement error of the SC algorithm was comparable to the other three methods used, with much faster processing time. The efficacy of the proposed technique was successfully demonstrated in both human brain MRS data and in a noisy MRS dataset acquired from a small volume‐of‐interest in the mouse brain. Conclusion: The study demonstrated the availability of a fast and robust technique that accurately corrects for both small and large frequency and phase shifts in MRS. [ABSTRACT FROM AUTHOR]

Pyruvate dehydrogenase complex deficiency (PDCD) is a mitochondrial disorder of carbohydrate oxidation characterized by lactic acidosis and central nervous system involvement. Knowledge of the affected metabolic pathways and clinical observations suggest that early initiation of the ketogenic diet may ameliorate the metabolic and neurologic course of the disease. We present a case in which first trimester ultrasound identified structural brain abnormalities prompting a prenatal molecular diagnosis of PDCD. Ketogenic diet, thiamine, and N‐acetylcysteine were initiated in the perinatal period with good response, including sustained developmental progress. This case highlights the importance of a robust neurometabolic differential diagnosis for prenatally diagnosed structural anomalies and the use of prenatal molecular testing to facilitate rapid, genetically tailored intervention. [ABSTRACT FROM AUTHOR]

Early diagnosis of ophthalmic manifestations of multiple sclerosis (MS) is quite complicated.The aim. To assess the degree of impairment of the pathways of the visual analyzer in patients with MS, taking into account the data of structural optical coherence tomography and magnetic resonance imaging.Material and methods. Four groups of patients were analyzed: three groups of MS patients with various changes in visual functions and a group of somatically healthy patients. Structural changes of the optic nerve were assessed according to OCT and magnetic resonance studies.Results. A decrease in the thickness of the nerve fiber layer was found in groups 2 and 3 in the lower temporal sector – to 29–44 μm, in the upper temporal sector – to 30–33 μm, in the lower nasal sectors – to 11–18 μm. The data of groups 1 and 4 were comparable (p = 0.22). MR tractography in groups 2 and 3 determined the MRI picture of rarefaction and signs of interruption of the pathways, respectively. MR spectroscopy at the level of the visual cortex revealed: a decrease in NAA/Cho in groups 2 and 3 by 13–23 % (the data of groups 1 and 4 were comparable); a decrease in NAA/Cr by 17 % in group 1, and by 23 % in groups 2 and 3, a decrease in Cho/Cr by 21 % in group 1, by 13.4 % – in group 2 and by 8 % – in group 3. At the level of visual radiance, a decrease was observed: NAA/Cho by 31.5 % – in group 1, by 39.5 % – in group 2 and by 50 % – in group 3; NAA/Cr by 21 % – in group 1, by 32–35 % – in groups 2 and 3, and an excess of Cho/Cr by an average of 22 % in all groups.Conclusion. The data obtained indicate degenerative changes in the pathways of the visual analyzer not only in MS patients with partial optic nerve atrophy, but also in patients with no complaints and clinically pronounced visual impairment.

Pituitary gland metastasis is an unusual event, and pituitary metastasis from lung adenocarcinoma is extremely rare and associated with poor prognosis. To date, approximately 16 cases have been reported. Symptoms of these lesions can mimic hypophysitis, that is a possible immune-related adverse event of ICIs (Immune Checkpoint Inhibitors). Pituitary metastases and hypophisitis are life-threatening diseases and making differential diagnosis is important, because therapy of these conditions is quite different. Differentiating a condition from the other one is difficult, because many imaging features are not specific. In this presented case, cross-sectional imaging, in particular Magnetic Resonance Imaging (MRI), has revealed itself helpful to suggest the diagnosis of pituitary metastasis rather than hypophysitis.

This case report describes the potential utility of MR spectroscopy and MR perfusion imaging in a patient with central nervous system involvement of Erdheim-Chester disease (ECD). A 57-year-old male presented with a variety of neurological symptoms, and conventional MRI of the brain showed multiple supratentorial and infratentorial findings that generated a wide differential diagnosis. Advanced MRI sequences along with subsequent CT imaging of the abdomen and ultimately a renal biopsy helped narrow the differential and confirm the diagnosis of ECD. Case reports of ECD are sporadic, and the role of advanced neuroimaging in diagnosing this disease has not been fully elucidated.

Aim. Patients with multiple brain metastases (BM) benefit from hippocampal-avoiding whole brain radiotherapy (HA-WBRT), the challenging and less available form of WBRT. This study explores potential of pre-radiotherapy (pre-RT) hippocampal magnetic resonance spectroscopy (MRS) measuring hippocampal neuronal density as an imaging surrogate and predictive tool for assessing neurocognitive functions (NCF). Methods. 43 BM patients underwent pre-RT hippocampal MRS. N-acetyl aspartate (NAA) concentration, a marker for neuronal density (weighted by creatine (Cr) and choline (Cho) concentrations), and neurocognitive function (NCF) tests (HVLT and BVMT) performed by certified psychologists were evaluated. Clinical variables and NAA concentrations were correlated with pre-RT NCFs. Results. HVLT and BVMT subtests showed pre-RT deterioration except for BVMT recognition. Significantly better NCFs were observed in women in HVLT subsets. Significantly higher NAA/Cr + Cho was measured in women (median 0.63 vs. 0.55; P=0.048) in the left hippocampus (no difference in the right hippocampus). In men, a positive correlation (0.51, P=0.018) between total brain volume and HVLT-TR, between left hippocampal NAA/Cr + Cho and HVLT-R (0.45, P=0.063), and between right hippocampal NAA/Cr + Cho and BVMT-recognition (0.49, P=0.054) was observed. In women, a borderline significant negative correlation was observed between left hippocampal NAA/Cr + Cho and BVMT-TR (-0.43, P=0.076) and between right NAA/Cr + Cho and HVLT-DR (-0.42, P=0.051). Conclusion. Borderline statistically significant correlations were observed with speculative interpretation underlying the challenges of hippocampal MRS as a surrogate for neurocognitive impairment. Further studies need to be done to ascertain the opportunities for imaging predictors of benefit from memory sparing radiotherapy.

Abstract Background Metabolic dysfunction-associated steatotic liver (MASLD) disease is the commonest hepatic cause of liver fibrosis and cirrhosis after the introduction of the direct acting antivirals and eradication of hepatitis C. MASLD is usually associated with metabolic syndrome and elevated inflammatory markers. Magnetic resonance spectroscopy (MRS) offers a non-invasive diagnostic, alternative to liver biopsy. This is a case–control diagnostic-accuracy study conducted on 40 patients in the Hepato-gastroenterology Unit in the Internal Medicine Department, Ain Shams University Hospitals, to study the role of MRI spectroscopy as a new diagnostic model for assessment of liver steatosis in non-diabetic MASLD patients compared to the standard ultrasound and clinical criteria. MASLD was diagnosed by a combination of a validated ultrasound hepatic steatosis score grading system and hepatic steatosis index using clinical and laboratory parameters. MRS was performed in all patients and fat peak, water peak, and fat fraction % were measured, and diagnostic accuracy of different MRS is compared to the US scoring and different laboratory and clinical parameters. To our knowledge this is the first study conducted on MRS in our region and Egypt. Results This study revealed no statistically significant difference between the two groups regarding HbA1C, creatinine, while there was highly statistically significant difference regarding fasting blood sugar, 2 h post-prandial glucose level, urine albumin, and low-density lipoprotein levels. Hepatic steatosis score grading by abdominal ultrasound on the 20 controls showed no fatty changes with grade 0 (50%), and on the 20 MASLD patients showed that 2 cases were grade 1 steatosis (5%), 9 cases were grade 2 steatosis (22.5%), and 9 cases were grade 3 steatosis (22.5%). The diagnostic accuracy of predicting hepatic steatosis using different MRS parameters: fat peak, water peak, and fat fraction had area under the curve of 99.9%, 88.6%, and 100%, respectively. The sensitivity and specificity of fat fraction in detecting hepatic steatosis were 100%. The sensitivity and specificity of the fat peak in detecting hepatic steatosis were 100% and 95%, respectively. Moreover, the sensitivity and specificity of the water peak in detecting the hepatic steatosis were 88.6% and 85%, respectively. There is a statistically significant correlation between the three MRS parameters and the abdominal ultrasound hepatic steatosis score grades. Conclusion MRS parameters: fat fraction, fat peak, and water peak, have high diagnostic accuracy for predicting the liver steatosis. Moreover, MRS has the added advantage of being a non-invasive and a tool with low radiation risk. MRS also shows the metabolic changes in the liver and could be an eligible outcome in therapeutic clinical trials.

Background: Advances in in vivo MRI techniques enable cerebral barrier transfer rates (Ktrans) measurement in patients with vascular cognitive impairment and dementia (VCID). However, a consensus has not been reached on the dynamic contribution and importance of cerebral barrier abnormalities to the differential diagnosis of dementia subtypes. Our goal was to investigate the dynamics of blood-brain barrier (BBB) and blood-CSF barrier (BCSFB) Ktrans in patients with VCID longitudinally and determine the effect of aging. Methods: We studied subjects at two time points over two years; they were 65.5 years of age (SD = 15.94, M/F = 24/14) at the first visit. We studied 38 patients, 18 of whom had two visits. We calculated the BBB and BCSFB Ktrans with dynamic contrast-enhanced T1 MR, and we used 1H-MR spectroscopy to measure N-acetylaspartate (NAA) levels in the white matter as a marker of injury. In addition, we measured CSF levels of active-matrix metalloproteinase-3 (MMP3) as an inflammatory biomarker to aid in patient clustering. Results: Longitudinal BBB measurements revealed variable dynamic behavior: after two years, the BBB Ktrans increased in 55% of patients and decreased in the remaining 45% unpredictably. We did not find a significant linear model of BBB Ktrans versus age for VCID. For healthy controls, the model was Ktrans = 0.0014 + 0.0002 × age, which was significant (p = 0.046). VCID patients showed a reduction in BCSFB Ktrans compared to healthy controls (p = 0.01). Combining NAA, CSF MMP3, and Ktrans in a clustering analysis separated patients into groups. Conclusion: These results suggest that BBB Ktrans in VCID is dynamic and BCSFB Ktrans reduced by age. By combining inflammatory biomarkers with BBB Ktrans data, it is possible to separate VCID patients into distinct groups with different underlying pathologies. [ABSTRACT FROM AUTHOR]

Background: Due to the ongoing organ shortage, marginal grafts with steatosis are more frequently used in liver transplantation, leading to higher occurrences of graft dysfunction. A histological analysis is the gold standard for the quantification of liver steatosis (LS), but has its drawbacks: it is an invasive method that varies from one pathologist to another and is not available in every hospital at the time of organ procurement. This study aimed to compare non-invasive diagnostic tools to a histological analysis for the quantification of liver steatosis. Methods: Male C57BL6J mice were fed with a methioninecholine-deficient (MCD) diet for 14 days or 28 days to induce LS, and were compared to a control group of animals fed with a normal diet. The following non-invasive techniques were performed and compared to the histological quantification of liver steatosis: magnetic resonance spectroscopy (MRS), CARS microscopy, 99mTc MIBI SPECT imaging, and a new near-infrared spectrometer (NIR-SG1). Results: After 28 days on the MCD diet, an evaluation of LS showed ≥30% macrovesicular steatosis. High correlations were found between the NIR-SG1 and the blinded pathologist analysis (R2 = 0.945) (p = 0.001), and between the CARS microscopy (R2 = 0.801 (p < 0.001); MRS, R2 = 0.898 (p < 0.001)) and the blinded pathologist analysis. The ROC curve analysis showed that the area under the curve (AUC) was 1 for both the NIR-SG1 and MRS (p = 0.021 and p < 0.001, respectively), while the AUC = 0.910 for the Oil Red O stain (p < 0.001) and the AUC = 0.865 for the CARS microscopy (p < 0.001). The AUC for the 99mTc MIBI SPECT was 0.640 (p = 0.013), and this was a less discriminating technique for LS quantification. Conclusions: The best-performing non-invasive methods for LS quantification are MRS, CARS microscopy, and the NIR-SG1. The NIR-SG1 is particularly appropriate for clinical practice and needs to be validated by clinical studies on liver grafts. [ABSTRACT FROM AUTHOR]

Background: Metabolic dysfunction-associated steatotic liver (MASLD) disease is the commonest hepatic cause of liver fibrosis and cirrhosis after the introduction of the direct acting antivirals and eradication of hepatitis C. MASLD is usually associated with metabolic syndrome and elevated inflammatory markers. Magnetic resonance spectroscopy (MRS) offers a non-invasive diagnostic, alternative to liver biopsy. This is a case–control diagnostic-accuracy study conducted on 40 patients in the Hepato-gastroenterology Unit in the Internal Medicine Department, Ain Shams University Hospitals, to study the role of MRI spectroscopy as a new diagnostic model for assessment of liver steatosis in non-diabetic MASLD patients compared to the standard ultrasound and clinical criteria. MASLD was diagnosed by a combination of a validated ultrasound hepatic steatosis score grading system and hepatic steatosis index using clinical and laboratory parameters. MRS was performed in all patients and fat peak, water peak, and fat fraction % were measured, and diagnostic accuracy of different MRS is compared to the US scoring and different laboratory and clinical parameters. To our knowledge this is the first study conducted on MRS in our region and Egypt. Results: This study revealed no statistically significant difference between the two groups regarding HbA1C, creatinine, while there was highly statistically significant difference regarding fasting blood sugar, 2 h post-prandial glucose level, urine albumin, and low-density lipoprotein levels. Hepatic steatosis score grading by abdominal ultrasound on the 20 controls showed no fatty changes with grade 0 (50%), and on the 20 MASLD patients showed that 2 cases were grade 1 steatosis (5%), 9 cases were grade 2 steatosis (22.5%), and 9 cases were grade 3 steatosis (22.5%). The diagnostic accuracy of predicting hepatic steatosis using different MRS parameters: fat peak, water peak, and fat fraction had area under the curve of 99.9%, 88.6%, and 100%, respectively. The sensitivity and specificity of fat fraction in detecting hepatic steatosis were 100%. The sensitivity and specificity of the fat peak in detecting hepatic steatosis were 100% and 95%, respectively. Moreover, the sensitivity and specificity of the water peak in detecting the hepatic steatosis were 88.6% and 85%, respectively. There is a statistically significant correlation between the three MRS parameters and the abdominal ultrasound hepatic steatosis score grades. Conclusion: MRS parameters: fat fraction, fat peak, and water peak, have high diagnostic accuracy for predicting the liver steatosis. Moreover, MRS has the added advantage of being a non-invasive and a tool with low radiation risk. MRS also shows the metabolic changes in the liver and could be an eligible outcome in therapeutic clinical trials. [ABSTRACT FROM AUTHOR]

Aim. Patients with multiple brain metastases (BM) benefit from hippocampal-avoiding whole brain radiotherapy (HA-WBRT), the challenging and less available form of WBRT. This study explores potential of pre-radiotherapy (pre-RT) hippocampal magnetic resonance spectroscopy (MRS) measuring hippocampal neuronal density as an imaging surrogate and predictive tool for assessing neurocognitive functions (NCF). Methods. 43 BM patients underwent pre-RT hippocampal MRS. N-acetyl aspartate (NAA) concentration, a marker for neuronal density (weighted by creatine (Cr) and choline (Cho) concentrations), and neurocognitive function (NCF) tests (HVLT and BVMT) performed by certified psychologists were evaluated. Clinical variables and NAA concentrations were correlated with pre-RT NCFs. Results. HVLT and BVMT subtests showed pre-RT deterioration except for BVMT recognition. Significantly better NCFs were observed in women in HVLT subsets. Significantly higher NAA/Cr + Cho was measured in women (median 0.63 vs. 0.55; P=0.048) in the left hippocampus (no difference in the right hippocampus). In men, a positive correlation (0.51, P=0.018) between total brain volume and HVLT-TR, between left hippocampal NAA/Cr + Cho and HVLT-R (0.45, P=0.063), and between right hippocampal NAA/Cr + Cho and BVMT-recognition (0.49, P=0.054) was observed. In women, a borderline significant negative correlation was observed between left hippocampal NAA/Cr + Cho and BVMT-TR (−0.43, P=0.076) and between right NAA/Cr + Cho and HVLT-DR (−0.42, P=0.051). Conclusion. Borderline statistically significant correlations were observed with speculative interpretation underlying the challenges of hippocampal MRS as a surrogate for neurocognitive impairment. Further studies need to be done to ascertain the opportunities for imaging predictors of benefit from memory sparing radiotherapy. [ABSTRACT FROM AUTHOR]

Cellular senescence is characterized by stable cell cycle arrest. Senescent cells exhibit a senescence‐associated secretory phenotype that can promote tumor progression. The aim of our study was to identify specific nuclear magnetic resonance (NMR) spectroscopy‐based markers of cancer cell senescence. For metabolic studies, we employed murine liver carcinoma Harvey Rat Sarcoma Virus (H‐Ras) cells, in which reactivation of p53 expression induces senescence. Senescent and nonsenescent cell extracts were subjected to high‐resolution proton (1H)‐NMR spectroscopy‐based metabolomics, and dynamic metabolic changes during senescence were analyzed using a magnetic resonance spectroscopy (MRS)‐compatible cell perfusion system. Additionally, the ability of intact senescent cells to degrade the extracellular matrix (ECM) was quantified in the cell perfusion system. Analysis of senescent H‐Ras cell extracts revealed elevated sn‐glycero‐3‐phosphocholine, myoinositol, taurine, and creatine levels, with decreases in glycine, o‐phosphocholine, threonine, and valine. These metabolic findings were accompanied by a greater degradation index of the ECM in senescent H‐Ras cells than in control H‐Ras cells. MRS studies with the cell perfusion system revealed elevated creatine levels in senescent cells on Day 4, confirming the 1H‐NMR results. These senescence‐associated changes in metabolism and ECM degradation strongly impact growth and redox metabolism and reveal potential MRS signals for detecting senescent cancer cells in vivo. [ABSTRACT FROM AUTHOR]

Background: MR spectroscopy is an additional sequence to evaluate lesion characteristics in the brain. Time Echo (TE) is crucial for analyzing MR spectroscopy metabolite. Purpose: This study aims to evaluate the best TE variations during MR spectroscopy examinations in brain lesions. Method: This research is an experimental quantitative study. Researchers used five samples focusing on the results of head multi-voxel spectroscopy charts with clinical lesions or masses that had been taken twice using TE 35 and TE 144. At each TE in each sample, three voxel areas were measured, namely normal, perilesional, and lesion. Each spectroscopy data result is processed individually through READY View software, automatically producing a spectroscopy graph pattern. The required data in this study is the value of each head spectroscopy metabolism: N-Acetyl Aspartate (NAA), Choline (Cho), Creatine (Cr), Myo-Inositol (MI), Lipids Lactate (LL). All statistical tests used the SPSS v.26 application. Result: Based on Paired T test results, NAA, Cho, Cr, and MI metabolites have p-values that account for 0.779 > 0.05; 0.179 > 0.05; 0.581 > 0.05; and 0.057 > 0.05. Based on the Wilcoxon Sign Rank test, the LL metabolite showed a p-value of 0.460 > 0.05. Conclusion: There is no significant difference between TE 35 ms and TE 144 ms during MR spectroscopy examinations.

Background: The ring enhancing lesions of the brain are one of the most commonly encountered abnormalities on neuroimaging and pose a challenging group of lesions with the variable possibilities of diagnosis under conventional Magnetic Resonance Imaging (MRI). Employing advanced techniques such as Magnetic Resonance Spectroscopy (MRS) could increase the success rates of the diagnosis. Materials and Methods: 40 patients were evaluated in this study who are referred to department of radiodiagnosis, Kurnool Medical college from December 2023 to May 2024 over a period of 6 months. MRI along with MRS was performed on PHILIPS INGENIA 1.5 T. Inclusion Criteria: All suspected cerebral ring enhancing lesions detected on MR studies were taken up for MR Spectroscopy. Exclusion Criteria: Patient having contraindications to MRI. Results: Out of the 40 patients who were evaluated, tuberculoma 18 (45%) is the most common pathology followed by NCC 10(25%), Abscesses 5 (12.5%), metastases 5(12.5%) and primary brain tumors 2(5%). Conclusion: MRI along with MRS is the most sensitive modality in the characterization of intracranial ring enhancing lesions. [ABSTRACT FROM AUTHOR]

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BackgroundAdvances in in vivo MRI techniques enable cerebral barrier transfer rates (Ktrans) measurement in patients with vascular cognitive impairment and dementia (VCID). However, a consensus has not been reached on the dynamic contribution and importance of cerebral barrier abnormalities to the differential diagnosis of dementia subtypes. Our goal was to investigate the dynamics of blood-brain barrier (BBB) and blood-CSF barrier (BCSFB) Ktrans in patients with VCID longitudinally and determine the effect of aging.MethodsWe studied subjects at two time points over two years; they were 65.5 years of age (SD = 15.94, M/F = 24/14) at the first visit. We studied 38 patients, 18 of whom had two visits. We calculated the BBB and BCSFB Ktrans with dynamic contrast-enhanced T1 MR, and we used 1H-MR spectroscopy to measure N-acetylaspartate (NAA) levels in the white matter as a marker of injury. In addition, we measured CSF levels of active-matrix metalloproteinase-3 (MMP3) as an inflammatory biomarker to aid in patient clustering.ResultsLongitudinal BBB measurements revealed variable dynamic behavior: after two years, the BBB Ktrans increased in 55% of patients and decreased in the remaining 45% unpredictably. We did not find a significant linear model of BBB Ktrans versus age for VCID. For healthy controls, the model was Ktrans = 0.0014 + 0.0002 × age, which was significant (p = 0.046). VCID patients showed a reduction in BCSFB Ktrans compared to healthy controls (p = 0.01). Combining NAA, CSF MMP3, and Ktrans in a clustering analysis separated patients into groups.ConclusionThese results suggest that BBB Ktrans in VCID is dynamic and BCSFB Ktrans reduced by age. By combining inflammatory biomarkers with BBB Ktrans data, it is possible to separate VCID patients into distinct groups with different underlying pathologies.

Introduction: Low back pain (LBP) is a prevalent health issue associated with morphological changes in paravertebral muscles. Magnetic resonance imaging (MRI) is effective in identifying muscle steatosis, with MR spectroscopy (MRS) considered the gold standard. However, MRS is limited by technical challenges, prompting interest in Dixon sequences for fat quantification. Materials and Methods: We conducted a study comparing Multi Echo VIBE Dixon with single-voxel MR spectroscopy in quantifying fat fractions in lumbar multifidus muscles of chronic LBP patients. Ninety-eight measurements from 49 patients were analysed. Qualitative and quantitative image analyses were performed, and statistical analysis was conducted using SPSS 27. Results: Significant positive correlation (correlation coefficient: 0.992, p < 0.001) was found between Dixon and MRS fat fraction measurements. Intra-class correlation coefficient was 0.991 (p < 0.001), indicating strong agreement. No proportion bias was observed. Factors such as age, sex, and spinal degeneration correlated positively with multifidus fat atrophy. Conclusion: T2*-corrected Dixon imaging aligns well with spectroscopic measurements, offering an accurate alternative for estimating paraspinal muscle fat content in chronic LBP patients. Further studies are needed to establish threshold values for Dixon imaging. Chronic LBP is associated with multifidus muscle atrophy and fat infiltration, highlighting the need for effective management strategies.

Hyperpolarization techniques significantly enhance the sensitivity of magnetic resonance (MR) and thus present fascinating new directions for research and applications with in vivo MR imaging and spectroscopy (MRI/S). Hyperpolarized 13C MRI/S, in particular, enables real-time non-invasive assessment of metabolic processes and holds great promise for a diverse range of clinical applications spanning fields like oncology, neurology, and cardiology, with a potential for improving early diagnosis of disease, patient stratification, and therapy response assessment. Despite its potential, technical challenges remain for achieving clinical translation. This paper provides an overview of the discussions that took place at the international workshop "New Horizons in Hyperpolarized 13C MRI," in March 2023 at the Bavarian Academy of Sciences and Humanities, Munich, Germany. The workshop covered new developments, as well as future directions, in topics including polarization techniques (particularly focusing on parahydrogen-based methods), novel probes, considerations related to data acquisition and analysis, and emerging clinical applications in oncology and other fields. [ABSTRACT FROM AUTHOR]

Background: Diabetic Striatopathy (DS) is a rare complication of a poor‐controlled Diabetes Mellitus consisting of sudden onset of movement disorders. To date, there is still poor knowledge about the pathogenesis. Case: We describe a 79 year old men affected by sudden onset hemichoreic movements whose cause was a non‐ketotic hyperglycaemia diagnosed despite the normal blood glucose levels thanks to brain CT and magnetic resonance imaging. Then, we introduce a new magnetic resonance spectroscopy (MRS) finding never described until today which allowed us to produce a new pathogenetic theory of a phenomenon still without definitive explanations. Literature Review: We performed a review of DS cases using the Medline database and we extracted main data regarding imaging findings. Conclusions: Thanks to our MRS we show new imaging findings never described until today, with a new pathogenetic explanation, since all the causative hypotheses produced during the past years have never found evidence. [ABSTRACT FROM AUTHOR]

Background Gall bladder carcinoma (GBC) is a challenging malignancy characterized by late-stage diagnosis and poor prognosis. Early detection and accurate staging are crucial for improving patient outcomes. Magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) offer non-invasive imaging modalities that may aid in the evaluation of GBC. Choline, a metabolite detected by MRS, has been implicated in tumor growth and may serve as a potential biomarker for GBC. This study aims to investigate the role of MRI and MRS in evaluating choline levels as biomarkers for GBC. Method A prospective observational study will be conducted involving patients with suspected or confirmed GBC referred to the Department of Radiology, AVBRH, Sawangi. Patients meeting inclusion criteria will undergo MRI scans and MRS examinations to assess tumor characteristics and choline levels. Data collected will include MRI images, MRS spectra, histopathological results, and clinical outcomes. Statistical analysis will be performed to examine correlations between MRI findings, choline levels, and histopathological characteristics. Expected Outcome It is anticipated that MRI and MRS will demonstrate utility in evaluating choline levels as imaging biomarkers for GBC. Correlations between choline levels, tumor characteristics, and clinical outcomes are expected to provide valuable insights into the role of choline in GBC pathogenesis and prognosis. If successful, MRI and MRS could serve as non-invasive tools for early detection, staging, and treatment response monitoring in GBC, ultimately leading to improved patient outcomes and management strategies.

PurposeDiffuse intrinsic pontine gliomas (DIPG) are highly aggressive tumors with no currently available curative therapy. This study evaluated whether measurements of in vivo cell metabolites using magnetic resonance spectroscopy (MRS) may serve as biomarkers of response to therapy, including progression.MethodsSingle-voxel MR spectra were serially acquired in two cohorts of patients with DIPG treated with radiation therapy (RT) with or without concurrent chemotherapy and prior to progression: 14 participants were enrolled in a clinical trial of adjuvant glioma-associated antigen peptide vaccines and 32 patients were enrolled who did not receive adjuvant vaccine therapy. Spearman correlations measured overall survival associations with absolute metabolite concentrations of myo-inositol (mI), creatine (Cr), and n-acetyl-aspartate (NAA) and their ratios relative to choline (Cho) during three specified time periods following completion of RT. Linear mixed-effects regression models evaluated the longitudinal associations between metabolite ratios and time from death (terminal decline).ResultsOverall survival was not associated with metabolite ratios obtained shortly after RT (1.9-3.8 months post-diagnosis) in either cohort. In the vaccine cohort, an elevated mI/Cho ratio after 2-3 doses (3.9-5.2 months post-diagnosis) was associated with longer survival (rho = 0.92, 95% CI 0.67-0.98). Scans performed up to 6 months before death showed a terminal decline in the mI/Cho ratio, with an average of 0.37 ratio/month in vaccine patients (95% CI 0.11-0.63) and 0.26 (0.04-0.48) in the non-vaccine cohort.ConclusionHigher mI/Cho ratios following RT, consistent with less proliferate tumors and decreased cell turnover, were associated with longer survival, suggesting that this ratio can serve as a biomarker of prognosis following RT. This finding was seen in both cohorts, although the association with OS was detected earlier in the vaccine cohort. Increased mI/Cho (possibly reflecting immune-effector cell influx into the tumor as a mechanism of tumor response) requires further study.

Primary central nervous system (CNS) lymphoma is a very rare aggressive non-Hodgkin disease that originates in CNS (brain, leptomeninges, spinal cord, or eyes). It seems to have increased over the last two decades in both immunocompromised and immunocompetent patients. Primary large B-cell lymphoma involving the cerebellopontine angle (CPA) is extremely rare: only 15 cases of large B-cell lymphoma of the CPA have been reported worldwide; based on our knowledge, no cases studied with MR Spectroscopy. Primary large B-cell lymphoma of the CPA must be differentiated from other cerebellopontine angle diseases, such as acoustic neuroma and meningioma. An early and accurate diagnosis of this neoplasm is necessary for the best management because it is a radiosensitive and chemosensitive tumor.Herein, we report a rare case of B-cell lymphoma involving the left CPA in a 65-year-old man who presented with 3 months of hearing loss on the left, illustrated by MR and TC imaging, highlighting how the MR Spectroscopy, thanks to their greater specificity, is decisive in achieving the correct diagnosis of primary lymphoma and differentiating it from acoustic schwannoma or meningioma. Therefore, in the suspicion of a malignant heteroplastic lesion of the CPA, we suggest including Spectroscopy in the MR study protocol.

Clinical translation of 7 tesla (T) MRI of the brain promises high image quality and potentially improved clinical diagnosis for patients compared to current standard lower field-strength MRI at 1.5 and 3T.Here we describe how physics principles underlying ultra-high field (UHF) strength MRI affect 7T image quality, and how these can be exploited to translate 7T brain imaging into clinical practice. UHF MRI profits from higher inherent signal-to-noise ratio (SNR) and a resultant increase in achievable spatial resolution or acceleration factors; increase in sensitivity to magnetic susceptibility differences and a higher amplitude of the Blood Oxygen Level Dependent (BOLD) signal; increase in longitudinal relaxation time; and increased frequency dispersion and spectral resolution in MR spectroscopy.Examples are presented of different brain pathologies, which are better illustrated on 7T compared to lower field strength by applying sequences and imaging techniques that exploit these intrinsic strengths of 7T MRI. This includes imaging of various vascular pathologies, epilepsy and brain tumours.

Background: Sellar and suprasellar regions are complex areas of the brain, where different varieties of lesions can occur in this confined space. When evaluating sellar and suprasellar lesions prior to surgery, diffusion weighted MRI and MR spectroscopy are regarded as crucial diagnostic tools that supplement conventional MRI. Aim of the Study: The aim of the recent study was to evaluate the role of the DWI and Single-Voxel 1H MRS Metabolites in characterization of Sellar and Suprasellar masses. Methods: A prospective study has been conducted on 30 patients with various sellar and suprasellar masses consulted from Neurosurgery and Neurology Departments to the MRI unit over a period of 6 months between June 2023 and Nov 2023.They were examined with long-echo single voxel 1H -MRS and DWI by 1.5 Tesla clinical imaging machine. Examinations were guided by cMRI. We confirmed our diagnosis pathologically after surgical management. Results: Sellar and suprasellar tumors exhibited variable values for diffusion and the mean ADC value was for macroadenoma is (0.72±0.25)x10-3 mm2/sec, craniopharyngeoma is (1.8±0.1)x10-3 mm2/sec, glioma is (1.38±0.5)x10-3 mm2/sec, germinoma (0.80±0.2)x10-3 mm2/sec and for meningioma is (0.94±0.16)x10-3 mm2/sec. Pituitary macroadenoma were typically characterized by Cr peak, moderate elevation of Cho peak and significant reduction of NAA,. Craniopharyngiomas were classically distinguished by notable reduction of all metabolites .Rise of Cho peak and decrease of NAA and Cr peaks typically characterize Gliomas. The most distinguishing metabolite of meningioma is Alanine. Conclusions: Diffusion-weighted MRI and MR Spectroscopy can contribute to presurgical assessment and discrimination between various sellar, suprasellar masses. [ABSTRACT FROM AUTHOR]

Macrophage activation, first generalized to the M1/M2 dichotomy, is a complex and central process of the innate immune response. Simply, M1 describes the classical proinflammatory activation, leading to tissue damage, and M2 the alternative activation promoting tissue repair. Given the central role of macrophages in multiple diseases, the ability to noninvasively differentiate between M1 and M2 activation states would be highly valuable for monitoring disease progression and therapeutic responses. Since M1/M2 activation patterns are associated with differential metabolic reprogramming, we hypothesized that hyperpolarized 13C magnetic resonance spectroscopy (HP 13C MRS), an innovative metabolic imaging approach, could distinguish between macrophage activation states noninvasively. The metabolic conversions of HP [1-13C]pyruvate to HP [1-13C]lactate, and HP [1-13C]dehydroascorbic acid to HP [1-13C]ascorbic acid were monitored in live M1 and M2 activated J774a.1 macrophages noninvasively by HP 13C MRS on a 1.47 Tesla NMR system. Our results show that both metabolic conversions were significantly increased in M1 macrophages compared to M2 and nonactivated cells. Biochemical assays and high resolution 1H MRS were also performed to investigate the underlying changes in enzymatic activities and metabolite levels linked to M1/M2 activation. Altogether, our results demonstrate the potential of HP 13C MRS for monitoring macrophage activation states noninvasively.

Background: This study aimed to develop a time-efficient method of acquiring simultaneous, dual-slice MR spectroscopic imaging (MRSI) for the evaluation of brain metabolism. Methods: Adaptive Hadamard-encoded pulses were developed and integrated with atlas-based automatic prescription. The excitation profiles were evaluated via simulation, phantom and volunteer experiments. The feasibility of γ-aminobutyric acid (GABA)-edited dual-slice MRSI was also assessed. Results: The signal between slices in the dual-band MRSI was less than 1% of the slice profiles. Data from a homemade phantom containing separate, interfacing compartments of creatine and acetate solutions demonstrated ~0.4% acetate signal contamination relative to the amplitude in the excited creatine compartment. The normalized signal-to-noise ratios from atlas-based acquisitions in volunteers were found to be comparable between dual-slice, Hadamard-encoded MRSI and 3D acquisitions. The mean and standard deviation of the coefficients of variation for NAA/Cho from the repeated volunteer scans were 8.2% ± 0.8% and 10.1% ± 3.7% in the top and bottom slices, respectively. GABA-edited, dual-slice MRSI demonstrated simultaneous detection of signals from GABA and coedited macromolecules (GABA+) from both superior grey and deep grey regions of volunteers. Conclusion: This study demonstrated a fully automated dual-slice MRSI acquisition using atlas-based automatic prescription and adaptive Hadamard-encoded pulses.

Traumatic brain injury (TBI) is a widespread and expensive problem globally. The standard diagnostic workup for new TBI includes obtaining a noncontrast computed tomography image of the head, which provides quick information on operative pathologies. However, given the limited sensitivity of computed tomography for identifying subtle but meaningful changes in the brain, magnetic resonance imaging (MRI) has shown better utility for ongoing management and prognostication after TBI. In recent years, advanced applications of MRI have been further studied and are being implemented as clinical tools to help guide care. These include functional MRI, diffusion tensor imaging, MR perfusion, and MR spectroscopy. In this review, we discuss the scientific basis of each of the above techniques, the literature supporting their use in TBI, and how they may be clinically implemented to improve the care of TBI patients.

Mutations in the FBXO28 gene, which encodes FBXO28, one of the F-box protein family, may cause developmental and epileptic encephalopathy (DEE). FBXO28 -related DEE is radiologically characterized by cerebral atrophy, delayed/abnormal myelination, and brain malformation; however, no neurochemical analyses have been reported. Case report: A female Japanese infant presented with severe psychomotor delay, epileptic spasms, and visual impairment. Whole-exome sequencing revealed a de novo variant of the FBXO28 gene, leading to the diagnosis of FBXO28 -related DEE. Magnetic resonance (MR) spectroscopy at 6, 12, and 32 months revealed decreased N -acetylaspartate and choline-containing compounds and increased levels of myoinositol. MR spectroscopy revealed neurochemical derangement in FBXO28 -related DEE, that is, disturbed myelination secondary to neuronal damage with astrogliosis. [ABSTRACT FROM AUTHOR]

Purpose: The inherently poor SNR of MRS measurements presents a significant hurdle to its clinical application. Denoising by machine or deep learning (DL) was proposed as a remedy. It is investigated whether such denoising leads to lower estimate uncertainties or whether it essentially reduces noise in signal‐free areas only. Methods: Noise removal based on supervised DL with U‐nets was implemented using simulated 1H MR spectra of human brain in two approaches: (1) via time‐frequency domain spectrograms and (2) using 1D spectra as input. Quality of denoising was evaluated in three ways: (1) by an adapted fit quality score, (2) by traditional model fitting, and (3) by quantification via neural networks. Results: Visually appealing spectra were obtained; hinting that denoising is well‐suited for MRS. However, an adapted denoising score showed that noise removal is inhomogeneous and more efficient for signal‐free areas. This was confirmed by quantitative analysis of traditional fit results as well as DL quantitation following DL denoising. DL denoising, although apparently successful as judged by mean squared errors, led to substantially biased estimates in both implementations. Conclusion: The implemented DL‐based denoising techniques may be useful for display purposes, but do not help quantitative evaluations, confirming expectations based on estimation theory: Cramér Rao lower bounds defined by the original data and the appropriate fitting model cannot be circumvented in an unbiased way for single data sets, unless additional prior knowledge can be incurred in the form of parameter restrictions/relations or applicable substates. [ABSTRACT FROM AUTHOR]

Multimodal neuroimaging data of various brain disorders provides valuable information to understand brain function in health and disease. Various neuroimaging-based databases have been developed that mainly consist of volumetric magnetic resonance imaging (MRI) data. We present the comprehensive web-based neuroimaging platform "SWADESH" for hosting multidisease, multimodal neuroimaging, and neuropsychological data along with analytical pipelines. This novel initiative includes neurochemical and magnetic susceptibility data for healthy and diseased conditions, acquired using MR spectroscopy (MRS) and quantitative susceptibility mapping (QSM) respectively. The SWADESH architecture also provides a neuroimaging database which includes MRI, MRS, functional MRI (fMRI), diffusion weighted imaging (DWI), QSM, neuropsychological data and associated data analysis pipelines. Our final objective is to provide a master database of major brain disease states (neurodegenerative, neuropsychiatric, neurodevelopmental, and others) and to identify characteristic features and biomarkers associated with such disorders. [ABSTRACT FROM AUTHOR]

(1) Background: X-linked creatine transporter deficiency (CTD) (OMIM 300036) is a rare group of inherited metabolic disorders characterized by global developmental delay/intellectual disability (GDD/ID), seizures, autistic behavior, and movement disorders. Pathogenic variants in the SLC6A8 gene, located at Xq28, are causative of the disease, leading to impaired creatine transport into the brain. Supplementation with creatine and its precursors, glycine and arginine, has been attempted, yet the treatment efficacy remains controversial. (2) Methods: Here we report a de novo SLC6A8 variant in a boy aged 3 years 9 months presenting with GDD, autistic behavior, and epilepsy. Elevated urinary creatine/creatinine ratio and diminished creatine peak on brain MR spectroscopy suggested the diagnosis of CTD. Genetic sequencing revealed a de novo hemizygous frameshift variant (NM_005629: c.1136_1137del, p. Glu379ValfsTer85). Creatine supplementation therapy was initiated after definitive diagnosis. Electroencephalography and MR spectroscopy were monitored during follow-up in concurrence with neuropsychological evaluations. The clinical phenotype and treatment response of CTD were summarized by systematic view of the literature. (3) Results: In silico analysis showed this variant to be deleterious, probably interfering with substrate binding and conformational changes during creatine transport. Creatine supplementation therapy led to seizure cessation and modest cognitive improvement after half-year's treatment. (4) Conclusions: This case highlights the importance of MR spectroscopy and metabolic screening in males with GDD/ID, allowing for early diagnosis and therapeutic intervention. Mechanistic understanding and case-per-se analysis are required to enable precision treatment for the patients. [ABSTRACT FROM AUTHOR]

Background: This study aimed to develop a time-efficient method of acquiring simultaneous, dual-slice MR spectroscopic imaging (MRSI) for the evaluation of brain metabolism. Methods: Adaptive Hadamard-encoded pulses were developed and integrated with atlas-based automatic prescription. The excitation profiles were evaluated via simulation, phantom and volunteer experiments. The feasibility of γ-aminobutyric acid (GABA)-edited dual-slice MRSI was also assessed. Results: The signal between slices in the dual-band MRSI was less than 1% of the slice profiles. Data from a homemade phantom containing separate, interfacing compartments of creatine and acetate solutions demonstrated ~0.4% acetate signal contamination relative to the amplitude in the excited creatine compartment. The normalized signal-to-noise ratios from atlas-based acquisitions in volunteers were found to be comparable between dual-slice, Hadamard-encoded MRSI and 3D acquisitions. The mean and standard deviation of the coefficients of variation for NAA/Cho from the repeated volunteer scans were 8.2% ± 0.8% and 10.1% ± 3.7% in the top and bottom slices, respectively. GABA-edited, dual-slice MRSI demonstrated simultaneous detection of signals from GABA and coedited macromolecules (GABA+) from both superior grey and deep grey regions of volunteers. Conclusion: This study demonstrated a fully automated dual-slice MRSI acquisition using atlas-based automatic prescription and adaptive Hadamard-encoded pulses. [ABSTRACT FROM AUTHOR]

This literature review presents a comprehensive overview of machine learning (ML) applications in proton MR spectroscopy (MRS). As the use of ML techniques in MRS continues to grow, this review aims to provide the MRS community with a structured overview of the state‐of‐the‐art methods. Specifically, we examine and summarize studies published between 2017 and 2023 from major journals in the MR field. We categorize these studies based on a typical MRS workflow, including data acquisition, processing, analysis, and artificial data generation. Our review reveals that ML in MRS is still in its early stages, with a primary focus on processing and analysis techniques, and less attention given to data acquisition. We also found that many studies use similar model architectures, with little comparison to alternative architectures. Additionally, the generation of artificial data is a crucial topic, with no consistent method for its generation. Furthermore, many studies demonstrate that artificial data suffers from generalization issues when tested on in vivo data. We also conclude that risks related to ML models should be addressed, particularly for clinical applications. Therefore, output uncertainty measures and model biases are critical to investigate. Nonetheless, the rapid development of ML in MRS and the promising results from the reviewed studies justify further research in this field. [ABSTRACT FROM AUTHOR]

Purpose: While 3D MR spectroscopic imaging (MRSI) provides valuable spatial metabolic information, one of the hurdles for clinical translation is its interpretation, with voxel-wise quality control (QC) as an essential and the most time-consuming step. This work evaluates the accuracy of machine learning (ML) models for automated QC filtering of individual spectra from 3D healthy control and patient datasets. Methods: A total of 53 3D MRSI datasets from prior studies (30 neurological diseases, 13 brain tumors, and 10 healthy controls) were included in the study. Three ML models were evaluated: a random forest classifier (RF), a convolutional neural network (CNN), and an inception CNN (ICNN) along with two hybrid models: CNN + RF, ICNN + RF. QC labels used for training were determined manually through consensus of two MRSI experts. Normalized and cropped real-valued spectra was used as input. A cross-validation approach was used to separate datasets into training/validation/testing sets of aggregated voxels. Results: All models achieved a minimum AUC of 0.964 and accuracy of 0.910. In datasets from neurological disease and controls, the CNN model produced the highest AUC (0.982), while the RF model achieved the highest AUC in patients with brain tumors (0.976). Within tumor lesions, which typically exhibit abnormal metabolism, the CNN AUC was 0.973 while that of the RF was 0.969. Data quality inference times were on the order of seconds for an entire 3D dataset, offering drastic time reduction compared to manual labeling. Conclusion: ML methods accurately and rapidly performed automated QC. Results in tumors highlights the applicability to a variety of metabolic conditions. [ABSTRACT FROM AUTHOR]

Background: Neuropathic pain following spinal cord injury (SCI) affects approximately 60% of individuals with SCI. Effective pharmacological and non-pharmacological treatments remain elusive. We recently demonstrated that our immersive virtual reality walking intervention (VRWalk) may be effective for SCI NP. Additionally, we found that SCI NP may result from a decrease in thalamic γ-aminobutyric-acid (GABA), which disturbs central sensorimotor processing. Objective: While we identified GABAergic changes associated with SCI NP, a critical outstanding question is whether a decrease in SCI NP generated by our VRWalk intervention causes GABA content to rise. Method: A subset of participants (n = 7) of our VRWalk trial underwent magnetic resonance spectroscopy pre- and post-VRWalk intervention to determine if the decrease in SCI NP is associated with an increase in thalamic GABA. Results: The findings revealed a significant increase in thalamic GABA content from pre- to post-VRWalk treatment. Conclusion: While the current findings are preliminary and should be interpreted with caution, pre- to post-VRWalk reductions in SCI NP may be mediated by pre- to post-treatment increases in thalamic GABA by targeting and normalizing maladaptive sensorimotor cortex reorganization. Understanding the underlying mechanisms of pain recovery can serve to validate the efficacy of home-based VR walking treatment as a means of managing pain following SCI. Neuromodulatory interventions aimed at increasing thalamic inhibitory function may provide more effective pain relief than currently available treatments. [ABSTRACT FROM AUTHOR]

Isocitrate dehydrogenase (IDH) mutation status is an important biomarker in the glioma-defining subtype and corresponding prognosis. This study proposes a straightforward method for 2-hydroxyglutarate (2-HG) quantification by MR spectroscopy for IDH mutation status detection and directly compares in vivo 2-HG MR spectroscopy with ex vivo 2-HG concentration measured in resected tumor tissue. Eleven patients with suspected lower-grade glioma (ten IDH1; one IDHwt) were prospectively included. Preoperatively, 3T point-resolved spectroscopy (PRESS) was acquired; 2-HG was measured as the percentage elevation of Glx3 (the sum of 2-HG and Glx) compared to Glx4. IDH mutation status was assessed by immunochemistry or direct sequencing. The ex vivo 2-HG concentration was determined in surgically obtained tissue specimens using gas chromatography–mass spectrometry. Pearson correlation was used for assessing the correlation between in vivo MR spectroscopy and ex vivo 2-HG concentration. MR spectroscopy was positive for 2-HG in eight patients, all of whom had IDH1 tumors. A strong correlation (r = 0.80, p = 0.003) between 2-HG MR spectroscopy and the ex vivo 2-HG concentration was found. This study shows in vivo 2-HG MR spectroscopy can non-invasively determine IDH status in glioma and demonstrates a strong correlation with ex vivo 2-HG concentration in patients with lower-grade glioma. [ABSTRACT FROM AUTHOR]

Methylmalonic acidemia (MMA) is a disorder of methylmalonic acid metabolism caused by impaired methylmalonyl CoA mutase. Neuroimaging shows symmetric hypodensity on CT, and T2 prolongation on MRI in the globus pallidus; however, there have been only a few reports on MR spectroscopy findings and no previous reports on arterial spin labeling (ASL), both of which could reflect neurochemical derangement in MMA. We herein report an 18-month-old Sri Lankan boy presented with severe acute exacerbation of MMA due to bacteremia of Salmonella sp. O7. MRI on the seventh day showed T1 and T2 prolongation with decreased diffusion in the bilateral globus pallidus. ASL revealed hyperperfusion in the bilateral globus pallidus. MR spectroscopy showed increased choline (Cho), myo-inositol (mIns), glutamine (Gln), and lactate (Lac) in the globus pallidus; and increased Gln and Lac in the white matter. The globus pallidus is the site of high energy demand around the age of 1 year. In severe acute exacerbation of MMA, increased anaerobic metabolism due to impaired mitochondrial function may lead to hyperperfusion in the globus pallidus to compensate for a disturbed energy supply. Increased Cho, mIns, and Lac in the globus pallidus may result from active demyelination, astrogliosis, and increased anaerobic metabolism. Increased Gln in the basal ganglia and white matter may reflect excitotoxicity.

Abstract Background The thalamus is crucial in the development of idiopathic generalized epilepsy (IGE), which could lead to cognitive dysfunctions, according to data from neuropsychology and advanced neuroimaging investigations. This research aimed to measure the metabolic changes in the thalamus and to assess if could be contributed to cognitive impairment in IGE patients. Thirty IGE patients and thirty healthy volunteers with matched ages, genders, and educational levels participated in this cross-sectional case–control research. The IGE patients and controls were evaluated neuropsychologically using Intelligence Quotient (IQ) to assess general cognitive ability, Digit span for attention, Wechsler memory scale (WMS) for verbal memory, cube drawing test for visuospatial memory, Trail making test for executive functions, and Controlled Oral Word Association test (COWAT) for verbal fluency and quantitative multi-voxel MR spectroscopy (MRS) measurements of N-acetyl aspartate (NAA), choline (Cho), creatine (Cr), NAA/Cr, NAA/Cho and Cho/Cr ratios at 1.5 T scanner. The voxels were located over the right and left thalamus. Results The IGE patients showed worse cognitive performance in IQ, attention, executive function, and verbal and visuospatial memory domains compared to the controls. The IGE patients exhibited a significantly decrease NAA in the right thalamus (p = 0.004) and a lower NAA/Cr ratio in the left thalamus (p = 0.01). the mean thalamus NAA level exhibited a positive correlation with CDT (r = 0.45, p = P = 0.01), and WMS-R (r = 0.39, p = 0.03) and a negative correlation with trail-making A test (r = 0.42, P = 0.01). Conclusions it was concluded that IGE patients exhibited poor cognition which could be attributed to thalamic neurometabolic changes due to impaired thalamic cortical circuits.