Magnetic Resonance Spectroscopy Examination Research Articles

Metabolic changes assessed by 1H MR spectroscopy in the corpus callosum of post-COVID patients.

Many patients with long COVID experience neurological and psychological symptoms. Signal abnormalities on MR images in the corpus callosum have been reported. Knowledge about the metabolic profile in the splenium of the corpus callosum (CCS) may contribute to a better understanding of the pathophysiology of long COVID. Eighty-one subjects underwent proton MR spectroscopy examination. The metabolic concentrations of total N-acetylaspartate (NAA), choline-containing compounds (Cho), total creatine (Cr), myo-inositol (mI), and NAA/Cho in the CCS were statistically compared in the group of patients containing 58 subjects with positive IgG COVID-19 antibodies or positive SARS-CoV-2 qPCR test at least two months before the MR and the group of healthy controls containing 23 subjects with negative IgG antibodies. An age-dependent effect of SARS-CoV-2 on Cho concentrations in the CCS has been observed. Considering the subjective threshold of age = 40years, older patients showed significantly increased Cho concentrations in the CCS than older healthy controls (p = 0.02). NAA, Cr, and mI were unchanged. All metabolite concentrations in the CCS of younger post-COVID-19 patients remained unaffected by SARS-CoV-2. Cho did not show any difference between symptomatic and asymptomatic patients (p = 0.91). Our results suggest that SARS-CoV-2 disproportionately increases Cho concentration in the CCS among older post-COVID-19 patients compared to younger ones. The observed changes in Cho may be related to the microstructural reorganization in the CCS also reported in diffusion measurements rather than increased membrane turnover. These changes do not seem to be related to neuropsychological problems of the post-COVID-19 patients. Further metabolic studies are recommended to confirm these observations.

A prospective observational role of magnetic resonance imaging and magnetic resonance spectroscopy in evaluation of choline levels in gall bladder carcinoma in tertiary care hospital in central India

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.

Altered metabolites in the periaqueductal gray of COVID-19 patients experiencing headaches: a longitudinal MRS study.

Headache is one of the most common symptoms of acute COVID-19 infection. However, its mechanisms remain poorly understood, and there is a lack of studies investigating changes in the periaqueductal gray (PAG) in COVID-19 patients exhibiting headaches. The study aimed to explore the alterations in metabolites of the PAG pre- and post-COVID-19 infection in individuals who suffered from headaches during the acute phase of the disease using proton magnetic resonance spectroscopy (1H-MRS). Fifteen participants who experienced headaches during the acute phase of COVID-19 were recruited. All subjects underwent two proton magnetic resonance spectroscopy (1H-MRS) examinations focusing on the PAG before and after they were infected. Metabolite changes were assessed between the pre- and post-infection groups. The combined glutamine and glutamate/total creatine ratio (Glx/tCr) was increased in the PAG following COVID-19 infection. The total choline/total creatine ratio (tCho/tCr) in the pre-infection group was negatively correlated with the duration of headache during the COVID-19 acute phase. The present study indicates that PAG plays a pivotal role in COVID-19 headaches, thereby supporting the involvement of trigeminovascular system activation in the pathophysiology of COVID-19 headaches.

Association between brain N-acetylaspartate levels and sensory and motor dysfunction in patients who have spinal cord injury with spasticity: an observational case-control study.

Spinal cord injury is a severe and devastating disease, and spasticity is a common and severe complication that is notoriously refractory to treatment. However, the pathophysiological mechanisms underlying spasticity and its development remain largely unknown. The goal of the present study was to find differences, if any, in metabolites of the left precentral gyrus and basal ganglia of patients who have spinal cord injury with or without spasticity, and to explore the relationship between the brain metabolite concentrations and clinical status. Thirty-six participants were recruited for magnetic resonance spectroscopic examination: 23 with spinal cord injury (12 with spasticity and 11 without spasticity) and 13 healthy controls. We acquired localized proton spectra from the precentral gyrus and basal ganglia via 10 mm3 voxels. Notably, univariate linear regression analysis demonstrated that the lower that the N-acetylaspartate concentration (a marker for neuronal loss) was in the precentral gyrus of the patients, the lower their ASIA (American Spinal Injury Association) light-touch scores, pinprick scores, and motor scores. Additionally, longer durations of injury were associated with higher N-acetylaspartate levels in the precentral gyrus. Compared with the healthy participants and patients without spasticity, N-acetylaspartate levels in the patients with spasticity were significantly lower in both the precentral gyrus and basal ganglia. Lower N-acetylaspartate levels also correlated with greater sensory and motor dysfunction in the patients who had spinal cord injury with spasticity.

Behavior during aging of bone-marrow fatty-acids profile in women's calcaneus to search for early potential osteoporotic biomarkers: a 1H-MR Spectroscopy study.

Identify new potential biomarkers of osteoporosis at an early stage, by magnetic resonance spectroscopy (MRS), studying early changes in the metabolic profile of bone-marrow fatty acids in women's calcanei during healthy aging and osteoporosis status. Single voxel MRS was performed by using a point resolved spectroscopy (PRESS) sequence at 3T. Thirty-four Caucasian women (age range: 22-59years) were recruited to investigate calcaneus bone marrow. The cohort was constituted of four groups according to age, menopausal status, and T-score evaluated after a DXA examination on the femoral neck. Women were classified in young control (n=11, mean age=26.5±3.8 y, age range: 22-34years), perimenopausal groups (n=11, mean age=42.0±3.6 y, age range: 37-47years), postmenopausal group (n=9, mean age=55.4±2.9 y, age range: 50-59years, mean T-score=-1.70±0.50) and osteoporotic group (n=6, mean age=53.0±2.8 y, age range: 50-58years, mean T-score=-2.54±0.10). The total lipid content (TL), the Unsaturation Index (UI), and the fraction of unsaturated/polyunsaturated fatty acid (fUFA and fPUFA) were calculated. TL was significantly correlated with age (r=0.73, p<0.001). TL increases linearly with age in the young + perimenopausal population (r=0.92, p<0.001) but this trend is not significant in the postmenopausal subject (r=0.48, p=0.07). No significant correlation was found between T-Score and TL in postmenopausal and osteoporotic women, whereas a significant correlation was found between TL and time interval (tp) between the age at menopause and the age of the subject at the MRS examination. Conversely, no correlation was found between T-score and tp. The unsaturation index (UI) does not significantly discriminate between osteoporotic, peri- and postmenopausal women. On the other hand, fUFA is significantly different in peri-menopausal and osteoporotic subjects (p=0.02), while fPUFA is significantly different both between peri- and postmenopausal women (p=0.05) and postmenopausal and osteoporotic subjects (p=0.03). Both fUFA and fPUFA did not correlate with subjects' age. In the female calcaneus, fUFA and fPUFA are promising measurable quantities for the characterization of bone marrow's composition potentially correlated with the development of osteoporosis, whereas UI does not differentiate between subjects of varying osteoporotic status. The fact that the TL in the calcaneus is correlated with tp, indicates that active metabolic changes are still occurring in these subjects, giving complementary information to the DXA about the changes in bone marrow's composition which may affect the whole bone health.

Glutathione in the Pons Is Associated With Clinical Status Improvements in Subacute Spinal Cord Injury.

In spinal cord injury (SCI), the primary mechanical injury is followed by secondary sequelae that develop over the subsequent months and manifests in biochemical, functional, and microstructural alterations, at the site of direct injury but also in the spinal cord tissue above and below the actual lesion site. Noninvasive magnetic resonance spectroscopy (MRS) can be used to assess biochemical modulation occurring in the secondary injury phase, in addition to and supporting conventional MRI, and might help predict and improve patient outcome. In this article, we aimed to examine the metabolic levels in the pons of subacute SCI by means of in vivo proton MRS at 3 T and explore the association to clinical scores. In this prospective study, between November 2015 and February 2018, single-voxel short-echo MRS data were acquired in healthy controls and in SCI subjects in the pons once during rehabilitation. Besides the single-point MRS examination, in addition, in participants with SCI, the clinical status (ie, motor, light touch, and pinprick scores) was assessed twice: (1) around the MRS session (approximately 10 weeks postinjury) and (2) before discharge (at approximately 9 months postinjury). The group differences were assessed with Kruskal-Wallis test, the post hoc comparison was assessed with Wilcoxon rank sum test, and the clinical correlations were conducted with Spearman rank correlation test. Bayes factor calculations completed the statistical part providing relevant evidence values. Twenty healthy controls (median age, 50 years; interquartile range, 41-55 years; 18 men) and 18 subjects with traumatic SCI (median age, 50 years; interquartile range, 32-58 years; 16 men) are included. Group comparison showed an increase of total N -acetylaspartate and combined glutamate and glutamine levels in complete SCI and a reduction of total creatine in incomplete paraplegic SCI. The proton MRS-based glutathione levels at baseline correlate to the motor score improvement during rehabilitation in incomplete subacute SCI. This exploratory study showed an association of the metabolite concentration of glutathione in the pons assessed at approximately 10 weeks after injury with the improvements of the motor score during the rehabilitation. Pontine glutathione levels in subjects with traumatic subacute incomplete SCI acquired remote from the injury site correlate to clinical score and might therefore be beneficial in the rehabilitation assessments.

Association between coffee consumption with serum lipid profile in ELSA-Brasil study: a metabolomic approach.

This study evaluated the association between coffee consumption and serum lipid profile in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). This is a cross-sectional study on baseline data from participants of the cohort ELSA-Brasil. Only participants of São Paulo Research Center who underwent a nuclear magnetic resonance (NMR) spectroscopy examination of lipid profile were included (N = 4736). Coffee intake was categorized into four categories (cups/day, in reference cup size of 50mL, which is the household measure adopted in Brazil): never/almost never, ≤ 1, 1-3, and > 3. Serum lipid profile [i.e., Total Cholesterol (TC), Total Triglycerides (TG), Very Low-Density Lipoprotein-cholesterol (VLDL-c), Low-Density Lipoprotein-cholesterol (LDL-c), High-Density Lipoprotein-cholesterol (HDL-c), Triglyceride-rich Lipoprotein Particles (TRLP) and subfractions particles] was analyzed. To estimate the effect of coffee consumption on serum lipid profile, multivariate Generalized Linear Models were performed. Compared to participants who never or almost never drink coffee, individuals who consumed more than 3 cups/day showed an increase in concentrations of TC (β: 4.13; 95% CI 0.81, 7.45), TG (β: 9.53; 95% CI 1.65, 17.42), VLDL-c (β: 1.90; 95% CI 0.38, 3.42), TRLP (β: 8.42; 95% CI 1.24, 15.60), and Very Small-TRLP and Medium-TRLP subfractions (β: 7.36; 95% CI 0.21, 14.51; β: 2.53; 95% CI 0.89, 4.16, respectively), but not with HDL-c and LDL-c. Among individuals with low (≤ 1 cup/day) and moderate (1-3 cups/day) coffee consumption, no significant associations with lipids was observed. High coffee consumption (more than 3 cups per day) was associated with an increase in serum lipids, namely TC, TG, VLDL-c, and TRL particles, highlighting the importance of a moderate consumption of this beverage.

Radiological Prediction of Isocitrate Dehydrogenase (IDH) Mutational Status and Pathological Verification for Lower-Grade Astrocytomas

Background and objectiveThe isocitrate dehydrogenase (IDH) status of patients with World Health Organization (WHO) grade II or III astrocytoma is essential for understanding its biological features and determining therapeutic strategies. This study aimed to use radiological analysis to predict the IDH status of patients with lower-grade astrocytomas and to verify the pathological implications.MethodsIn this study, 47 patients with grade II (17 cases) or III astrocytomas (30 cases), based on 2016 WHO Classification, underwent methionine (MET) positron emission tomography (PET) and magnetic resonance spectroscopy (MRS) on the same day between January 2013 and June 2020. The patients were retrospectively assessed. Immunohistochemistry showed 23 cases of IDH-mutant and 24 of IDH-wildtype. Based on fluid-attenuated recovery inversion (FLAIR)/T2 imaging, three doctors blinded to clinical data independently allocated 18 patients to the clear boundary group between the tumor and the normal brain and 29 to the unclear boundary group. The peak ratios of N-acetylaspartate (NAA)/creatine (Cr), choline (Cho)/Cr, and Cho/NAA and the tumor-to-normal region (T/N) ratio for maximum accumulation in MET-PET were calculated. For statistical analysis, Fisher’s exact test was used to assess associations between two variables, and the Mann-Whitney U test to compare the values between the IDH-wildtype and IDH-mutant groups. The optimal cut-off values of MET T/N ratio and MRS parameters for discriminating IDH-wildtype from IDH-mutant were obtained using receiver operating characteristics curves.ResultsThe unclear boundary group had significantly more IDH-wildtype cases than the clear boundary group (P<0.001). The IDH-wildtype group had significantly lower Cho/Cr (<1.84) and Cho/NAA (<1.62) ratios (P=0.02 and P=0.047, respectively) and a higher MET T/N ratio (>1.44, P=0.02) than the IDH-mutant group. The odds for the IDH-wildtype were 0.22 for patients who fulfilled none of the four criteria, including boundary status and three ratios, and 0.9 for all four criteria.ConclusionsThese results suggest that the combination of MRI, MRS, and MET-PET examination could be helpful for the prediction of IDH status in WHO grade II/III gliomas.

Childhood trauma history is linked to abnormal brain metabolism of non-medicated adult patients with major depressive disorder

ObjectivesChildhood trauma is a risk factor that may lead to persistent brain metabolic abnormalities, predisposing individuals to major depressive disorder (MDD). To better elucidate the pathogenesis of MDD, we investigated the neurometabolic changes in unmedicated MDD patients who had experienced childhood trauma (CT). MethodsIn this study, 37 unmedicated MDD patients with CT, 35 unmedicated MDD patients without CT, and 30 healthy control participants underwent high-resolution proton magnetic resonance spectroscopy (1H-MRS) examination. Bilateral metabolic ratios of N-acetylaspartate (NAA)/creatine (Cr) and choline (Cho)/Cr in the prefrontal white matter (PWM), anterior cingulate cortex (ACC), putamen, and cerebellum were obtained. ResultsMDD patients showed neurometabolic changes in the cortico-striato-cerebellar (CSC) circuit. Furthermore, MDD patients showed significantly lower NAA/Cr and higher Cho/Cr ratio in the bilateral ACC and putamen, and higher NAA/Cr and lower Cho/Cr ratio in the cerebellum. Childhood trauma reduced the Cho/Cr ratio in the left ACC, which played an important role in longer and more episodes of depression. ConclusionEarly childhood trauma has a long-lasting impact on the metabolism of adult MDD patients, leading to abnormal choline metabolism of the left ACC. Abnormal biochemical metabolism in the CSC circuit may be an underlying pathophysiology of MDD. LimitationAs this is a small cross-sectional study, the impact of childhood trauma on the different stages of depression has not been observed.

Diagnostic Accuracy of Magnetic Resonance Spectroscopy in Diagnosing Carcinoma Prostate

Background: Magnetic resonance spectroscopy (1H-MRS) produces a non-invasive analysis of the metabolism of the tissue, determining the relative concentrations of their metabolites and the interactions produced between them, which may be used in tumor diagnosis and showed good diagnostic accuracy for prostate cancer detection. Objective: To determine the diagnostic accuracy of Magnetic Resonance Spectroscopy (MRS) in diagnosing prostate cancer. Methodology: This was a cross sectional study, conducted at department of Radiology, Bahawal Vitoria Hospital, Bahawalpur, from July 2019 to June 2020. A total of 206 male patients with clinical suspicion of carcinoma prostate, 50-80 years of age will be included. Patients with already diagnosed carcinoma prostate, prostatic abscess, acute or chronic prostatitis were excluded. Each patient has undergone MRS examination. Each MRS was interpreted by one consultant radiologist and was looked for choline + creatine/citrate ratio for carcinoma prostate. Findings of MRS and histopathology were correlated. Data were analyzed by using SPSS 20. Results: In 120 MRS-positive patients, 108 were True Positive and 12 were False Positive. Among, 86 MRS negative patients, 16 were False Negative whereas 70 were True Negative. Overall sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of magnetic resonance spectroscopy (MRS) in diagnosing carcinoma prostate was 87.10%, 85.37%, 90.0% 81.40%, and 86.41% respectively. Conclusion: This study concluded that Magnetic Resonance Spectroscopy is the non-invasive modality of choice with high diagnostic accuracy in detecting prostate cancer.

Brain metabolic differences between temporal lobe epileptic seizures and organic non-epileptic seizures in postictal phase: a retrospective study with magnetic resonance spectroscopy.

Magnetic resonance spectroscopy (MRS) is employed to investigate the brain metabolites differences between patients with temporal lobe epileptic seizures (TLES) and organic non-epileptic seizures (ONES) that appear to be epileptic seizures. Twenty-three patients with TLES and nine patients with ONES in postictal phase underwent MRS examinations on a clinical 1.5T system, with 15 healthy controls in comparison. Statistical analyses on the ratios of brain metabolites were performed using the Mann-Whitney U test with age as a covariate. The results showed that N-acetyl-aspartate/Creatine (NAA/Cr) ratio of patients with TLES was statistically different from that of patients with ONES in postictal phase, i.e., TLES 1.422±0.037, ONES 1.640±0.061, P=0.012 in left temporal pole, while TLES 1.470±0.052, ONES 1.687±0.084, P=0.023 in the right temporal pole. Besides, compared with healthy controls, patients with TLES in postictal phase present significant differences in ratios of NAA/Cr, N-acetyl-aspartate/Choline (NAA/Cho) and NAA/(Cho + Cr). Experimental results demonstrate that NAA/Cr can be used to discriminate TLES from ONES, which has not been found in the references to the best of our knowledge. Although a prospective controlled validation is needed in the future, this retrospective study reveals that MRS may provide useful metabolites information to facilitate the epilepsy diagnosis.

Research progress on mechanism and imaging of temporal lobe injury induced by radiotherapy for head and neck cancer.

Radiotherapy (RT) is an effective treatment for head and neck cancer (HNC). Radiation-induced temporal lobe injury (TLI) is a serious complication of RT. Late symptoms of radiation-induced TLI are irreversible and manifest as memory loss, cognitive impairment, and even temporal lobe necrosis (TLN). It is currently believed that the mechanism of radiation-induced TLI involves microvascular injury, neuron and neural stem cell injury, glial cell damage, inflammation, and the production of free radicals. Significant RT-related structural changes and dose-dependent changes in gray matter (GM) and white matter (WM) volume and morphology were observed through computed tomography (CT) and magnetic resonance imaging (MRI) which were common imaging assessment tools. Diffusion tensor imaging (DTI), dispersion kurtosis imaging (DKI), susceptibility-weighted imaging (SWI), resting-state functional magnetic resonance (rs-fMRI), magnetic resonance spectroscopy (MRS), and positron emission tomography (PET) can be used for early diagnosis and prognosis evaluation according to functional, molecular, and cellular processes of TLI. Early diagnosis of TLI is helpful to reduce the incidence of TLN and its related complications. This review summarizes the clinical features, mechanisms, and imaging of radiation-induced TLI in HNC patients. KEY POINTS: • Radiation-induced temporal lobe injury (TLI) is a clinical complication and its symptoms mainly include memory impairment, headache, and cognitive impairment. • The mechanisms of TLI include microvascular injury, cell injury, and inflammatory and free radical injury. Significant RT-related structural changes and dose-dependent changes in TL volume and morphology were observed through CT and MRI. • SWI, MRS, DTI, and DKI and other imaging examinations can detect anatomical and functional, molecular, and cellular changes of TLI.

Spectral Wavelet-feature Analysis and Classification Assisted Denoising for enhancing magnetic resonance spectroscopy.

Magnetic resonance spectroscopy (MRS) is capable of revealing important biochemical and metabolic information of tissues noninvasively. However, the low concentrations of metabolites often lead to poor signal-to-noise ratio (SNR) and a long acquisition time. Therefore, the applications of MRS in detection and quantitative measurements of metabolites in vivo remain limited. Reducing or even eliminating noise can improve SNR sufficiently to obtain high quality spectra in addition to increasing the number of signal averaging (NSA) or the field strength, both of which are limited in clinical applications. We present a Spectral Wavelet-feature ANalysis and Classification Assisted Denoising (SWANCAD) approach to differentiate signal and noise peaks in magnetic resonance spectra based on their respective wavelet features, followed by removing the identified noise components to improve SNR. The performance of this new denoising approach was evaluated by measuring and comparing SNRs and quantified metabolite levels of low NSA spectra (e.g. NSA = 8) before and after denoising using the SWANCAD approach or by conventional spectral fitting and denoising methods, such as LCModel and wavelet threshold methods, as well as the high NSA spectra (e.g. NSA = 192) recorded in the same sampling volumes. The results demonstrated that SWANCAD offers a more effective way to detect the signals and improve SNR by removing noise from the noisy spectra collected with low NSA or in the subminute scan time (e.g. NSA = 8 or 16 s). The potential applications of SWANCAD include using low NSA to accelerate MRS acquisition while maintaining adequate spectroscopic information for detection and quantification of the metabolites of interest when a limited time is available for an MRS examination in the clinical setting.

Study on different pathogenic factors in different disease stages of patients with Wilson disease

To investigate in different stages of patients with Wilson disease (WD), there are different pathogenic factors such as metal deposition, oxidative stress, and inflammatory response in the brain. A total of 32 untreated WD patients and 10 normal controls were enrolled in the study. The neurological symptoms were evaluated using the modified Young scale. Liver function, metal metabolism, susceptibility-weighted imaging (SWI), diffusion tensor imaging (DTI), and magnetic resonance spectroscopy (MRS) examination were done. The clinical disease stages were divided into metal deposition period, fiber damage period, and neuronal necrosis period according to the imaging results. The content of 24-h urine copper, serum copper, and serum iron; and the levels of catalase (CAT), glutathione peroxidase (GSH-PX), malondialdehyde (MDA), nitric oxide (NO), nitric oxide synthase (NOS), superoxide dismutase (SOD), interleukin (IL-1), and tumor necrosis factor alpha (TNF-α) were detected. The contents of urinary copper in WD patients at neuronal necrosis stage were lower than those in patients at the metal deposition stage (P = 0.011) and fiber injury stage (P = 0.023). The contents of NOS (P = 0.039) and NO (P = 0.047) in WD patients at the stage of fiber injury were higher than those of the normal control, while GSH-PX (P = 0.025) and CAT (P = 0.041) were lower in the neuronal necrosis stage. In the stage of neuronal necrosis, the levels of IL-1 (P = 0.030) and TNF-α were higher than those of the normal control (P = 0.042). The neurological symptom scores in patients with fiber injury (P = 0.013) and neuron injury were higher than those with metal deposition (P = 0.026). There are different pathogenic factors in different stages of WD. At the neuronal necrosis stage, copper deposition was decreased in WD patients. In the stage of fiber injury and neuronal necrosis, there is oxidative stress injury in WD patients. In the neuronal necrosis phase, WD patients have an inflammatory response.

Brain radionecrosis after radiation therapy for atypical meningioma

Introduction. Atypical Meningioma (AM) is at high risk of local failure. The role of radiation therapy (XRT) as an adjuvant to surgical resection is incompletely defined. The most deleterious consequence of brain-directed XRT is radiation necrosis. Brain radionecrosis (BRN) after AM has been rarely reported. The relevant literature is reviewed, highlighting its diagnostic challenges. Case Presentation. We report a 25-year-old male with a BRN after adjuvant XRT for AM, which has been misdiagnosed as a recurrent neoplastic lesion upon magnetic resonance spectroscopy (MRS) examination. Surgery and histopathological description were made and yielded a definitive diagnosis of BRN. The patient was treated by dexamethasone with concomitant hyperbaric oxygen therapy (HBO2). The patient showed a further progression of the disease. Therefore, he was elected to receive bevacizumab. However, the patient finally died for refractory brain edema. Conclusion. BRN is a relatively rare instance after XRT for AM. There is no single modality that can reliably distinguish BRN from tumour recurrence. Therefore, reaching an early prompt treatment decision is challenging.

Predictive value of magnetic resonance spectroscopy combined with diffusion weighted imaging in patients with secondary brain insult after spontaneous intra-cerebral hemorrhage

To investigate the correlations between the changes of N-acetylaspartate/creatine (NAA/Cr) detected by magnetic resonance spectroscopy (MRS), and of the relative apparent diffusion coefficient (rADC) detected by diffusion weighted imaging (DWI) and the occurrence and outcome of secondary brain injury (SBI) in patients with spontaneous intra-cerebral hemorrhage (SICH). One hundred and eight SICH patients diagnosed by CT from January 2014 to December 2019 in the First People's Hospital of Huzhou were selected as the research objects. MRS and DWI examinations were performed on day 2 after admission. The body temperature, blood pressure, blood glucose, blood sodium, arterial oxygen partial pressure (PaO2) and other indexes were continuously monitored. The patients were divided into two groups: SBI group (46 cases) and control group (62 cases) according to whether there were secondary brain injury factors (SBIF). The differences in NAA/Cr and rADC of the edema area and Glasgow outcome score (GOS) after 6 months were compared between the two groups; multivariate Logistic regression analysis was used to analyze the risk factors of SBI. The NAA/Cr and rADC of perihematoma edema area and GOS after 6 months in SBI group were significantly lower than those in control group [NAA/Cr: 1.64±0.35 vs. 1.87±0.41, rADC: 2.57±0.39 vs. 2.75±0.45, GOS after 6 months (points): 3.47±0.59 vs. 3.76±0.65], with significant differences (all P < 0.05). Logistic regression analysis showed that NAA/Cr and rADC were the risk factors for the occurrence of SBI [odds ratio (OR) values were 0.172, 0.343, 95% confidence intervals (95%CI) were 0.048-0.609 and 0.118-0.996, respectively, both P < 0.05]. MRS combined with DWI has a certain value in predicting SBI after SICH. SBI can aggravate brain injury and affect the prognosis of patients. SBI should be actively prevented and intervention, carried out.

Intracellular Phosphate and ATP Depletion Measured by Magnetic Resonance Spectroscopy in Patients Receiving Maintenance Hemodialysis.

The precise origin of phosphate that is removed during hemodialysis remains unclear; only a minority comes from the extracellular space. One possibility is that the remaining phosphate originates from the intracellular compartment, but there have been no available data from direct assessment of intracellular phosphate in patients undergoing hemodialysis. We used phosphorus magnetic resonance spectroscopy to quantify intracellular inorganic phosphate (Pi), phosphocreatine (PCr), and βATP. In our pilot, single-center, prospective study, 11 patients with ESKD underwent phosphorus (31P) magnetic resonance spectroscopy examination during a 4-hour hemodialysis treatment. Spectra were acquired every 152 seconds during the hemodialysis session. The primary outcome was a change in the PCr-Pi ratio during the session. During the first hour of hemodialysis, mean phosphatemia decreased significantly (-41%; P<0.001); thereafter, it decreased more slowly until the end of the session. We found a significant increase in the PCr-Pi ratio (+23%; P=0.001) during dialysis, indicating a reduction in intracellular Pi concentration. The PCr-βATP ratio increased significantly (+31%; P=0.001) over a similar time period, indicating a reduction in βATP. The change of the PCr-βATP ratio was significantly correlated to the change of depurated Pi. Phosphorus magnetic resonance spectroscopy examination of patients with ESKD during hemodialysis treatment confirmed that depurated Pi originates from the intracellular compartment. This finding raises the possibility that excessive dialytic depuration of phosphate might adversely affect the intracellular availability of high-energy phosphates and ultimately, cellular metabolism. Further studies are needed to investigate the relationship between objective and subjective effects of hemodialysis and decreases of intracellular Pi and βATP content. Intracellular Phosphate Concentration Evolution During Hemodialysis by MR Spectroscopy (CIPHEMO), NCT03119818.

THE DETECTION OF ELEVATED CHOLINE METABOLITE IN MAGNETIC RESONANCE SPECTROSCOPY TO DIFFERENTIATE BETWEEN BENIGN AND MALIGNANT BONE TUMOR

Objective: This study was aimed to determine the accuracy of elevated choline metabolite in Magnetic Resonance Spectroscopy (MRS) at bone tumor to differentiate between benign and malignant according to their pathology result. Materials and Methods: A retrospective study of 40 samples consisted of benign and malignant bone tumor patients who met the inclusion criteria, who had MRS examination from January 2019 to January 2020. Elevated choline metabolite was used to differentiate between benign and malignant lesions based on their pathological result. From this study, we got sensitivity value, specificity value, PPV(positive predictive value), NPV(negative predictive value) and accuracy value. Results: The total number of patients were 40 who had bone tumor. The 11 benign tumors, consisted of 8 giant cell tumors (GCT), 1 aneurysmal bone cyst (ABC) and 2 abscesses on MRS the 7 of 8 GCTs and 1 ABC did not show elevated choline metabolite in MRS. One GCT and 2 abscesses showed elevated choline metabolite in their respective MRS. The 29 malignant cases consisted of 19 osteosarcomas, 2 chondrosarcomas, 2 plasmacytomas, 1 malignant GCT and 5 metastatic bone diseases. All but one case did not show elevated choline metabolite in their MRS and that was osteosarcoma. Conclusion: Elevated choline metabolite of proton MRS have higher sensitivity, specificity, PPV, NPV and accuracy to differentiate between benign and malignant bone tumor according to pathological result.

Terminology and concepts for the characterization of in vivo MR spectroscopy methods and MR spectra: Background and experts' consensus recommendations.

With a 40‐year history of use for in vivo studies, the terminology used to describe the methodology and results of magnetic resonance spectroscopy (MRS) has grown substantially and is not consistent in many aspects. Given the platform offered by this special issue on advanced MRS methodology, the authors decided to describe many of the implicated terms, to pinpoint differences in their meanings and to suggest specific uses or definitions. This work covers terms used to describe all aspects of MRS, starting from the description of the MR signal and its theoretical basis to acquisition methods, processing and to quantification procedures, as well as terms involved in describing results, for example, those used with regard to aspects of quality, reproducibility or indications of error. The descriptions of the meanings of such terms emerge from the descriptions of the basic concepts involved in MRS methods and examinations. This paper also includes specific suggestions for future use of terms where multiple conventions have emerged or coexisted in the past.

Analisis Prosedur Pemeriksaan Magnetic Resonance Spectroscopy (MRS) Pada Kasus Tumor Otak

Background: Magnetic Resonance Spectroscopy (MRS) is a method for measuring or assessing changes in the chemical elements of brain tissue in abnormalities such as tumours, stroke, epilepsy, metabolic disorder, infections, and neurodegenerative disease. MRS sequences require techniques to suppress fat and water signals, so the value of metabolic elements such as NAA Choline, Creatine, Lipids, and Lactate not been covered by fat and water. The peak amplitude of metabolic elements in MRS depends on the parameter used in the MRS sequences especially TE. Some studies suggest that variation and combinations of TE can provide more complete information on metabolite element, and can even be used to grading tumour stages.Methods: Type of this research is a qualitative study with an observational approach. Data collection was conducted in June 2019 at Radiology Department with observation method, unstructured interview, and documentation related to Magnetic Resonance Spectroscopy procedures. Data processing and analysis are carried out descriptively related to the result of observation, interview, and documentation.Results: The Head MR Spectroscopy examination procedure is a follow-up procedure of contrast MRI of the head. The main metabolite elements assessed on MRS are NAA, Choline, and Creatine, while those calculated and analyzed are the Area Under Cover (AUC) Integrals which are a collection of NAA and Choline signals. MRS sequences use Multi Voxel Spectroscopy (MVS). Chemical Shift Imaging (CSI) is used to suppress fat and water signals. TE parameter used in MRS sequences is only intermediate 135 ms.