Multivoxel Proton Magnetic Resonance Spectroscopy Research Articles

The prognostic value of proton magnetic resonance spectroscopy in term newborns treated with therapeutic hypothermia following asphyxia

ObjectiveThe purpose of this study was to correlate brain metabolism assessed shortly after therapeutic hyperthermia by 1H magnetic resonance spectroscopy (MRS), with neurodevelopmental outcome. MethodsAt the age of 6.0±1.8days, brain metabolites of 35 term asphyxiated newborns, treated with therapeutic hypothermia, were quantified by multivoxel proton MRS of a volume cranial to the corpus callosum, containing both gray and white matter. At the age of 30months the Bayley Scale of Infant Development-III was performed. ResultsInfants that died had lower gray matter NAA levels than infants that survived (P=0.005). In surviving infants (28 of 35) there was a trend of negative correlation between gray matter choline levels and gross motor outcome (r=−0.45). In the white matter, choline correlated negatively with fine motor skills (r=−0.40), and creatine positively with gross motor skills (r=0.58, P=0.02). There was no relationship between lactate levels and outcome. ConclusionMRS of asphyxiated neonates treated by therapeutic hypothermia can serve as predictor of outcome. Unlike previously reported associations in untreated asphyxiates, lactate levels had no relationship with outcome, which indicates that one of the working mechanisms of therapeutic hypothermia is reduction of the metabolic rate.

Diffusion-Weighted Imaging and Proton Magnetic Resonance Spectroscopy Findings in Osteosarcoma Versus Normal Muscle

Objectives: The goal of our study was to assess diffusion-weighted (DW) imaging and proton magnetic resonance (MR) spectroscopy findings in osteosarcoma versus normal muscle at 3 Tesla (3 T) MR system. Patients and Methods: Nineteen patients highly suspicious for osteosarcoma and 12 normal young healthy adults were enrolled in this study. Two patients were excluded from the study due to incompatible histopathologic results. DW imaging and multivoxel proton MR spectroscopy at 3 T were performed for all participants. Surgical biopsy and histopathological examination were done for every patient after imaging. SPSS 20 was used for statistical analysis. Results: The minimum apparent diffusion coefficient (ADC) value of osteosarcoma (0.88 ± 0.28) in this study confirms the significant restriction of this tumor against the dark background of normal muscle in high b-value images. Fourteen (82%) of the available 17 patients had ADC values ≤ 1 × 10-3 mm2/s. The maximum choline/creatine (Cho/Cr) ratio of osteosarcoma (1.94 ± 1.12) was statistically higher than the normal muscle (1.34 ± 0.11). Receiver operating curve (ROC) analysis (the area under the curve = 0.7) indicated a maximum Cho/Cr ratio of 1.37 as the cut point between the normal muscle and osteosarcoma, with a sensitivity, specificity and accuracy of 58.8%, 83.3%, and 69%, respectively. All patients with Cho/Cr ratios more than the cut point had ADC values ≤ 1 × 10-3 mm2/s and all patients with ADC values higher than 1 × 10-3 mm2/s had Cho/Cr ratios ≤ 1.37. Conclusion: It was concluded that DW imaging and proton MR spectroscopy are two effective noninvasive techniques in the evaluation of osteosarcoma.

Multivoxel proton magnetic resonance spectroscopy detects thalamic neurochemical metabolic changes in patients with major depressive disorder

BackgroundMajor depressive disorder (MDD) is one of the most commonly encountered psychiatric disorders in daily medical practice. Severity of depression may relate to thalamic neurochemical metabolic changes. Proton magnetic resonance spectroscopy (1H-MRS) can give an idea about the mechanisms that possibly underlie MDD and the response to therapy. Aim of the workTo detect the possible neurochemical metabolic changes that may occur in both thalami of patients with MDD by multivoxel 1H-MRS of the brain. Materials and methodsForty-three drug-naïve patients with MDD and 15 age- and sex-matched normal controls were subjected to brain imaging with multivoxel 1.5T 1H-MRS for measuring the NAA/Cho, NAA/Cr, Cho/Cr, mI/NAA and mI/Cr ratios in the thalamus bilaterally. The severity of depression was assessed by the Hamilton Depression Rating Scale (HDRS). ResultsPatients with MDD showed a significant decrease in the NAA/Cr and NAA/Cho ratios in both thalami compared to normal controls (P<0.05). Also, the severity of depression was significantly associated with decreased thalamic NAA/Cr and NAA/Cho ratios. ConclusionThe multi-voxel 1H-MRS can provide an insight to the neurochemical metabolic changes occurring in both thalami in patients with MDD. Increased severity of depression is significantly related to these thalamic neurochemical changes.

Multivoxel magnetic resonance spectroscopy identifies enriched foci of cancer stem-like cells in high-grade gliomas.

ObjectiveThis study investigated the correlation between choline/creatine (Cho/Cr) ratios determined by multivoxel proton magnetic resonance spectroscopy (1H-MRS) and the distribution of cancer stem-like cells (CSLCs) in high-grade gliomas.Patients and methodsSixteen patients with high-grade gliomas were recruited and underwent 1H-MRS examination before surgery to identify distinct tumor regions with variable Cho/Cr ratios. Using intraoperative neuronavigation, tumor tissues were accurately sampled from regions with high and low Cho/Cr ratios within each tumor. The distribution of CSLCs in samples from glioma tissue regions with different Cho/Cr ratios was quantified by neurosphere culture, immunohistochemistry, and Western blot.ResultsThe mean neurosphere formation rate in tissues with high Cho/Cr ratios was significantly increased compared with that in low Cho/Cr ratio tissues (13.94±5.94 per 100 cells vs 8.04±3.99 per 100 cells, P<0.001). Immunohistochemistry indicated that tissues with high Cho/Cr ratios had elevated expression of CD133, nestin, and CD15, relative to low Cho/Cr ratio tissue samples (23.6%±3.8% vs 18.3%±3.3%, 25.2%±4.5% vs 19.8%±2.8%, 24.5%±3.8% vs 17.8%±2.2%, respectively; all P<0.001). Western blot demonstrated that relative CD133 and nestin protein expression in high Cho/Cr ratio regions was significantly higher than that in low Cho/Cr ratio tissue samples (0.50±0.17 vs 0.30±0.08, 0.45±0.13 vs 0.27±0.07, respectively; both P<0.001). The protein expression levels of CD133 and nestin were highly correlated with Cho/Cr ratios (r=0.897 and r=0.861, respectively).ConclusionCho/Cr ratios correlate with the distribution of CSLCs in high-grade gliomas, and this may assist in identifying foci enriched with CSLCs and thus improve the management of high-grade gliomas.

Metabolic Changes in the Bilateral Visual Cortex of the Monocular Blind Macaque: A Multi-Voxel Proton Magnetic Resonance Spectroscopy Study.

The metabolic changes accompanied with adaptive plasticity in the visual cortex after early monocular visual loss were unclear. In this study, we detected the metabolic changes in bilateral visual cortex of normal (group A) and monocular blind macaque (group B) for studying the adaptive plasticity using multi-voxel proton magnetic resonance spectroscopy (1H-MRS) at 32months after right optic nerve transection. Then, we compared the N-Acetyl aspartate (NAA)/Creatine (Cr), myoinositol (Ins)/Cr, choline (Cho)/Cr and Glx (Glutamate + glutamine)/Cr ratios in the visual cortex between two groups, as well as between the left and right visual cortex of group A and B. Compared with group A, in the bilateral visual cortex, a decreased NAA/Cr and Glx/Cr ratios in group B were found, which was more clearly in the right visual cortex; whereas the Ins/Cr and Cho/Cr ratios of group B were increased. All of these findings were further confirmed by immunohistochemical staining. In conclusion, the difference of metabolic ratios can be detected by multi-voxel 1H-MRS in the visual cortex between groups A and B, which was valuable for investigating the adaptive plasticity of monocular blind macaque.

Roles of multi-voxel proton magnetic resonance spectroscopy for identifying low- and high-grade gliomas

Objective To investigate the roles of multi-voxel proton magnetic resonance spectroscopy for identifying low- and high-grade gliomas. Methods From January 2015 to December 2015, 53 consecutive patients with brain glioma diagnosed pathologically at the Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University were enrolled. There were 29 patients in the low-grade group and 24 in the high-grade group. SIEMENS Prisma 3 T magnetic resonance scanner performed conventional magnetic resonance scanning and 1H-MRS scanning before procedure. The choline (Cho)/N- acetyl aspartate (NAA) of the region of interest at same parts of the side of tumor and contralateral side (unaffected side) was obtained according to the 1H-MRS results. The ratios of mean values of Cho/NAA and the maximum values in both groups were compared. Receiver operating characteristic (ROC) curve was used to analyze the Cho/NAA value and assess the efficiency of glioma grade. Results Compared with contralateral same area of the same group, the mean value of Cho/NAA in the tumor parenchyma areas of the low- and high-grade groups increased significantly. There was significant difference (all P<0.001). Compared with the low-grade group, the maximum ratio, mean value, side of tumor and the ratio of contralateral Cho/NAA mean values of the tumor parenchyma Cho/NAA in the high-grade group were all increased. There were significant differences (all P<0.01). The ROC curve analysis showed that the Cho/NAA maximum ratio of tumor parenchyma, the mean value of Cho/NAA, the ratios of the mean values of the side of tumor and contralateral Cho/NAA for diagnosis of the area under the curve of the different grade gliomas were 0.7938 (the sensitivity and specificity were 54.6% and 92.9% respectively) and 0.7581 (the sensitivity and specificity were 59.1% and 78.6% respectively), and 0.7386 (the sensitivity and specificity were 45.5% and 92.9% respectively). Conclusion 1H-MRS detection of Cho/NAA has clinical application value for identifying the low-grade and high-grade gliomas. Key words: Glioma; Magnetic resonance imaging; Proton magnetic resonance spectroscopy; Multi-voxel

Correlation between neurochemical metabolism and memory function in adolescent patients with depression: A multi‐voxel 1H magnetic resonance spectroscopy study

We utilized multi-voxel proton magnetic resonance spectroscopy ((1)H-MRS) to detect biochemical abnormalities in dorsolateral prefrontal white matter and anterior cingulate gray matter and to determine the correlation of biochemical changes with memory function in depressed adolescents. A total of 24 depressed patients and 23 healthy controls were enrolled in this study. MRS was performed to assess the N-acetylaspartate (NAA)/creatine Cr and choline (Cho)/Cr ratios in dorsolateral prefrontal white matter and anterior cingulate gray matter of participants. Memory function was measured on the basis of Wechsler Memory Scale scores, and depression was diagnosed on the basis of clinical observation, interview, and Hamilton Depression Rating Scale scores. Compared with controls, depressed patients had significantly lower NAA/Cr and Cho/Cr ratios in left dorsolateral prefrontal white matter and lower NAA/Cr ratios in right dorsolateral prefrontal white matter (P < 0.05). No biochemical differences were identified in the bilateral anterior cingulate gray matter between the two groups. Nevertheless, the depressed patients showed significantly lower memory quotient than controls (P < 0.05). The NAA/Cr ratio in dorsolateral prefrontal white matter positively correlated with memory quotient (left: P < 0.01; right: P < 0.05). These findings suggest that biochemical abnormalities in prefrontal white matter are involved in the pathophysiology of adolescent depression. In particular, such abnormalities are already present at the early stage of the disorder, and low NAA/Cr in bilateral anterior frontal white matter may be associated with memory impairment and related neuropathology.

Assessing Temporal Brain Metabolite Changes in Preterm Infants Using Multivoxel Magnetic Resonance Spectroscopy.

Purpose:To investigate temporal changes in brain metabolites during the first year of life in preterm infants using multivoxel proton magnetic resonance spectroscopy (1H-MRS).Methods:Seventeen infants born at 29 (25–33) gestational week (median, range) weighing 1104 (628–1836) g underwent 1.5-T multivoxel 1H-MRS at 42 postconceptional week (PCW) and at 3, 6, 9, and 12 months after. We measured N-acetyl aspartate (NAA)/creatine (Cr), choline (Cho)/Cr, myo-inositol (Ins)/Cr, NAA/Cho, and Ins/Cho ratios in the frontal lobe (FL) and basal ganglia and thalamus (BG + Th). Linear regression analyses were performed to identify longitudinal changes in infants showing normal imaging findings and normal development. We also evaluated ratios of subjects with abnormal imaging findings and/or development using the 95% confidence intervals (CIs) of regression equations in normal subjects.Results:In the 13 infants with normal development, NAA/Cr and NAA/Cho ratios showed significant positive correlations with PCWs in the FL (r = 0.64 and 0.83, respectively, both P < 0.01) and BG + Th (r = 0.79 and 0.87, respectively, both P < 0.01), while Cho/Cr and Ins/Cr ratios revealed significant negative correlations with PCWs in the FL (r =−0.69 and −0.58, respectively, both P < 0.01) and BG + Th (r = −0.74 and −0.72, respectively, both P < 0.01). Ins/Cho ratios in the FL did not significantly correlate with PCWs (r = −0.19, P = 0.18), while those in the BG + Th showed significant negative correlation with PCWs (r = −0.44, P < 0.01). The metrics in the abnormal group were within the normal group 95% CIs in all periods except a few exceptions.Conclusions:Longitudinal multivoxel MRS is able to detect temporal changes in major brain metabolites during the first year of life in preterm infants.

The correlation between biochemical abnormalities in frontal white matter, hippocampus and serum thyroid hormone levels in first-episode patients with major depressive disorder

BackgroundPrevious neuroimaging studies found evidence of potential brain biochemical abnormalities in patients with major depressive disorder (MDD). Abnormal serum thyroid hormone levels were also found in MDD patients, which may correlated with the abnormal biochemical metabolism of brain. However, they rarely excluded the compounding effects of medication, and brain degeneration. This study sought to investigate the relationship between the biochemical metabolism and the serum thyroid hormone levels in first-episode, treatment-naive, non-late-life patients with MDD. Methods26 first-episode, treatment-naive, non-late-life patients with MDD and 13 healthy controls were enrolled in this study. Participants underwent two-dimensinal multivoxel proton magnetic resonance spectroscopy (1H MRS) [repetition time (TR)=1000ms; echo-time (TE)=144ms] at 1.5T to obtain bilateral metabolite levels from the white matter in prefrontal (WMP) lobe, anterior cingulate cortex (ACC), and hippocampus. The ratios of N-acetylaspartate (NAA)/creatine (Cr) and choline containg compounds (Cho)/creatine (Cr) were calculated. Morning serum free triiodothyronine (FT3), free thyroxin (FT4), total triiodothyronine (T3), total thyroxin (T4), and thyroid-stimulating hormone (TSH) were measured before antidepressant treatment. ResultsOn the comparison of brain biochemical changes, MDD patients had a significantly lower NAA/Cr ratio in the left WMP, and lower NAA/Cr and Cho/Cr ratios in the right WMP when compared to the controls. There were no significant differences in the metabolite ratios in the bilateral ACC, and hippocampus. On the comparison of serum thyroid hormone levels, MDD patients had a significantly decreased T3 and TSH levels. On the comparison of correlation of brain biochemical changes and serum thyroid hormone levels in patients with MDD, the NAA/Cr ratio in the right WMP was positively correlated with the level of TSH. ConclusionThese findings suggest that biochemical abnormalities and thyroid dysfunction may emerge early in the course of MDD. Dysfunction of neuronal function in the WMP may correlate with the abnormal TSH in patients with MDD, which may be related to the neuropathology of depression.

Multivoxel proton magnetic resonance spectroscopy of inflammatory and neoplastic lesions of the canine brain at 3.0 T

To describe findings of 3.0-T multivoxel proton magnetic resonance spectroscopy ((1)H-MRS) in dogs with inflammatory and neoplastic intracranial disease and to determine the applicability of (1)H-MRS for differentiating between inflammatory and neoplastic lesions and between meningiomas and gliomas. 33 dogs with intracranial disease (19 neoplastic [10 meningioma, 7 glioma, and 2 other] and 14 inflammatory). 3.0-T multivoxel (1)H-MRS was performed on neoplastic or inflammatory intracranial lesions identified with conventional MRI. N-acetylaspartate (NAA), choline, and creatine concentrations were obtained retrospectively, and metabolite ratios were calculated. Values were compared for metabolites separately, between lesion categories (neoplastic or inflammatory), and between neoplastic lesion types (meningioma or glioma) by means of discriminant analysis and 1-way ANOVA. The NAA-to-choline ratio was 82.7% (62/75) accurate for differentiating neoplastic from inflammatory intracranial lesions. Adding the NAA-to-creatine ratio or choline-to-creatine ratio did not affect the accuracy of differentiation. Neoplastic lesions had lower NAA concentrations and higher choline concentrations than inflammatory lesions, resulting in a lower NAA-to-choline ratio, lower NAA-to-creatine ratio, and higher choline-to-creatine ratio for neoplasia relative to inflammation. No significant metabolite differences between meningiomas and gliomas were detected. (1)H-MRS was effective for differentiating inflammatory lesions from neoplastic lesions. Metabolite alterations for (1)H-MRS in neoplasia and inflammation in dogs were similar to changes described for humans. Use of (1)H-MRS provided no additional information for differentiating between meningiomas and gliomas. Proton MRS may be a beneficial adjunct to conventional MRI in patients with high clinical suspicion of inflammatory or neoplastic intracranial lesions.

Magnetic resonance spectroscopy in prefrontal white matter of bipolar II disorder and its relation with executive function

Objective To explore the magnetic resonance spectroscopy characteristics of prefrontal white matter in bipolar Ⅱ disorder and its relation with executive function. Methods Thirty bipolar Ⅱ disorder patients and twenty healthy controls were evaluated with Multi-Voxel proton magnetic resonance spectroscopy(1H-MRS)scans on prefrontal white matter to assess the N-acetyl-aspartate (NAA), Choline (Cho), Creatine (Cr) and myo-inositol (MI), and then the ratios of NAA/Cr, Cho/Cr, MI/Cr, NAA/Cho and NAA/Cho+ Cr were calculated.All subjects were assessed for executive function using the Wisconsin Card Sorting Test (WCST). Results NAA/Cr in right prefrontal white matter(1.43±0.26) and NAA/Cr, NAA/Cho, NAA/Cho+ Cr in left prefrontal white matter(separately1.40±0.29, 1.13(1.53, 0.24), 0.62±0.12) were lower than healthy controls(separately 1.58±0.18, 1.59, 0.23, 1.30(0.53±0.29), 0.71±0.08)(P<0.05). The correct trials and the number of categories of WCST in Bipolar Ⅱ disorder (separately 26.97±8.97, 3(6, 3)) were less than in healthy controls(separately 36.35±4.85, 5(3, 2)), and perseverative errors and random errors were more in patients(separately 12.77±5.73, 7(21, 5)) than healthy controls(separately 7.35±3.01, 4(13, 2)). NAA/Cho and NAA/Cho+ Cr in left prefrontal white matter were positively correlated with correct trials, number of categories, and negatively related with perseverative errors(P<0.05). Conclusions Bilateral prefrontal white matter fiber damage occurs to bipolar Ⅱ disorder. And left prefrontal white matter fiber damage in bipolar Ⅱ disorder may lead to executive impairment. Key words: Bipolar Ⅱ disorder; Magnetic resonance spectroscopy; Executive function; Frontal lobe

Automated differentiation of glioblastomas from intracranial metastases using 3T MR spectroscopic and perfusion data

Differentiation of glioblastomas from metastases is clinical important, but may be difficult even for expert observers. To investigate the contribution of machine learning algorithms in the differentiation of glioblastomas multiforme (GB) from metastases, we developed and tested a pattern recognition system based on 3T magnetic resonance (MR) data. Single and multi-voxel proton magnetic resonance spectroscopy (1H-MRS) and dynamic susceptibility contrast (DSC) MRI scans were performed on 49 patients with solitary brain tumors (35 glioblastoma multiforme and 14 metastases). Metabolic (NAA/Cr, Cho/Cr, (Lip [Formula: see text] Lac)/Cr) and perfusion (rCBV) parameters were measured in both intratumoral and peritumoral regions. The statistical significance of these parameters was evaluated. For the classification procedure, three datasets were created to find the optimum combination of parameters that provides maximum differentiation. Three machine learning methods were utilized: Naïve-Bayes, Support Vector Machine (SVM) and [Formula: see text]-nearest neighbor (KNN). The discrimination ability of each classifier was evaluated with quantitative performance metrics. Glioblastoma and metastases were differentiable only in the peritumoral region of these lesions ([Formula: see text]). SVM achieved the highest overall performance (accuracy 98%) for both the intratumoral and peritumoral areas. Naïve-Bayes and KNN presented greater variations in performance. The proper selection of datasets plays a very significant role as they are closely correlated to the underlying pathophysiology. The application of pattern recognition techniques using 3T MR-based perfusion and metabolic features may provide incremental diagnostic value in the differentiation of common intraaxial brain tumors, such as glioblastoma versus metastasis.

Comparative study of high-grade gliomas and brain metasmses with multivoxel proton magnetic resonance spectroscopy

Objective To investigate the value in MR spectrum in differential diagnosis between high grade gliomas and metastases.Methods 30 cases of patients who confirmed by histopathologic findings or clinical follow-up were collected.Using a GE Signa EXCITE HD 3.0T super conduct MR unit,all the cases of patients were performed conventional MR scan and mutlti-voxel with 2-D mutlti-voxel PRESS 144 ms.Functool software was used for post-processing of spectrum.The ratios of NAA/Cr,NAA/Cho,Cho/Cr were measured in the solid part of masses,circum of tumors and contralateral parenchyma respectively.The result was used as the statistical method by SPSS13.0 software.Results In the solid part of masses,there were significant differences between high grade gliomas and metastases in the ratios of Cho/NAA( P ＜0.05),but no differences in the ratios of Cho/Cr,NAA/Cr;In peritumoral edema,there were significant differences in the ratios of Cho/Cr,Cho/NAA ( P ＜ 0.05),but no significant differences in the ratios of NAA/Cr(P ＜ 0.05).Conclusion 1H-MRS is very important and useful in the evaluation of differential diagnosis between high grade gliomas and metastases.The inspections of the ratios of Cho/Cr,Cho/NAA of gliomas and metastases peritumoral edema are important methods,especially for solitary metastases. Key words: 1H-magnetic resonance spectroscopy; Gliomas; Multivoxel; Differential diagnosis

Magnetic resonance imaging and proton magnetic resonance spectroscopy in the diagnosis of prostate carcinoma

To estimate the diagnostic possibilities of magnetic resonance imaging (MRI) techniques and three-dimensional multivoxel proton magnetic resonance spectroscopy (MRS) in patients with clinical suspicion of prostate carcinoma. 36 patients suspected to have prostate carcinoma underwent MRI with dynamic contrast enhanced study and MRS at 1.5T MRI unit using a pelvic phased array coil. MRI and MRS results were correlated with pathohystological findings after radical prostatectomy and standard biopsy with 12 or 24 cores or guided biopsy. Out of 44 detected prostate carcinomas, 38 (86.36%) demonstrated low T2W signal intensity while pathognomonic contrast enhancement has been detected in 40 (91%) carcinomas. MRS showed (Cho+Cr)/Ci ratio mean value of 3.52 in carcinoma, and 0.14 in normal prostatic tissue (p < 0.01). MR techniques, both nonenhanced and contrast enhanced when combined with MRS can provide reliable diagnostic results in the evaluation of prostate carcinoma even by use of pelvic phased array coil at 1.5T unit.

Metabolite concentration ratios in thalami of patients with migraine and trigeminal neuralgia measured with 1H-MRS

Objective: To investigate the metabolite concentration ratios including N-acetylaspartate (NAA), choline-containing compounds (Cho) and creatine plus phosphocreatine (Cr) in thalami of patients with migraine without aura, patients with trigeminal neuralgia and healthy comparison subjects using multi-voxel proton magnetic resonance spectroscopy (1H-MRS).Methods: 1H-MRS was performed with a 3.0 T MR system on the thalamus bilaterally in 20 patients with migraine without aura, 16 patients with trigeminal neuralgia and 14 healthy control subjects.Results: In the patients with trigeminal neuralgia, metabolite concentration ratios except for Cho/Cr in thalami were different from those of healthy subjects (p>0.05). In migraine group, only NAA/Cho is low in the left thalamus (p>0.05). Comparing the metabolite concentration ratios of affected and contralateral sides in migraine and trigeminal neuralgia groups, only NAA/Cr showed a significant difference (p>0.05).Conclusion: It was proved that migraine and trigeminal neuralgia seemed to be associated with an abnormal balance of the neural activity in the thalamus using 1H-MRS. There was some significant difference between metabolite concentration ratios in two diseases. 1H-MRS may serve as a useful non-invasive tool for evaluating thalamic neural activity and therapy effect in clinical performance of patients with migraine without aura.

Costello Syndrome: Cognitive and Proton Magnetic Resonance Spectroscopy Findings—A Case Report

The authors describe a girl with Costello syndrome who showed cerebral palsy and neurosensorial deafness. Brain computer tomography and magnetic resonance findings were normal. Multivoxel proton magnetic resonance spectroscopy showed a lowering of the peak of choline with a reduced choline/creatine ratio at the level of the centrum semiovale. These findings might be due to a congenital dysmyelinating or hypomyelinating condition. A complete neuroimaging study can play a relevant role to better clarify the pathogenesis of brain involvement in Costello syndrome.

Multivoxel proton MRS for differentiation of radiation-induced necrosis and tumor recurrence after gamma knife radiosurgery for brain metastases

Multivoxel proton magnetic resonance spectroscopy (MRS) was used for differentiation of radiation-induced necrosis and tumor recurrence after gamma knife radiosurgery for intracranial metastases in 33 consecutive cases. All patients presented with enlargement of the treated lesion, increase of perilesional brain edema, and aggravation or appearance of neurological signs and symptoms on average 9.3 +/- 4.9 months after primary treatment. Metabolic imaging defined four types of lesions: pure tumor recurrence (11 cases), partial tumor recurrence (11 cases), radiation-induced tumor necrosis (10 cases), and radiation-induced necrosis of the peritumoral brain (1 case). In 1 patient, radiation-induced tumor necrosis was diagnosed 9 months after radiosurgery; however, partial tumor recurrence was identified 6 months later. With the exception of midline shift, which was found to be more typical for radiation-induced necrosis (P < 0.01), no one clinical, radiologic, or radiosurgical parameter either at the time of primary treatment or at the time of deterioration showed a statistically significant association with the type of the lesion. Proton MRS-based diagnosis was confirmed histologically in all surgically treated patients (7 cases) and corresponded well to the clinical course in others. In conclusion, multivoxel proton MRS is an effective diagnostic modality for identification of radiation-induced necrosis and tumor recurrence that can be used for monitoring of metabolic changes in intracranial neoplasms after radiosurgical treatment. It can be also helpful for differentiation of radiation-induced necrosis of the tumor and that of the peritumoral brain, which may have important clinical and medicolegal implications.

Evaluation of cerebral metabolism by multi-voxel proton magnetic resonance spectroscopy imaging before and after STA-MCA bypass

Evaluation of cerebral metabolism by multi-voxel proton magnetic resonance spectroscopy imaging before and after STA-MCA bypass

Posterior cingulate metabolic changes in frontotemporal lobar degeneration detected by magnetic resonance spectroscopy.

Differences in prognosis and symptomatic treatment have highlighted the importance of the differential diagnosis of frontotemporal lobar degeneration (FTLD) and other dementias, but the variable clinical features make diagnosis difficult. We studied metabolic changes using multivoxel proton magnetic resonance spectroscopy (MRS) in regions of FTLD, including the posterior cingulate gyrus, which is also the area most affected by Alzheimer's disease (AD) in the early stages. We examined six patients with FTLD, six with presumed AD, and five healthy volunteers using repetition and echo times of 2000 and 135 ms. We analysed peak ratios of choline (Cho), creatine (Cr), and N-acetylaspartate (NAA) from frontal and temporoparietal regions, basal ganglia, and posterior cingulate gyrus in both hemispheres. A decreased NAA/Cr ratio was observed in the posterior cingulate gyri in presumed AD (right: 1.56+/-0.44, P =0.011; left: 1.46+/-0.25, P =0.008) and FTD (right: 1.47+/-0.40, P =0.005; left: 1.36+/-0.32, P =0.002). No statistically significant changes in Cho/Cr were identified in the posterior cingulate gyri in presumed AD or FTLD, and no differences were observed in peak ratios in other regions. Decreased NAA may reflect neuronal activity in the posterior cingulate gyrus, and this study may contribute to insights into the pathophysiology of FTLD.

Focal and lateralized subcortical abnormalities in unipolar major depressive disorder: an automated multivoxel proton magnetic resonance spectroscopy study

Background The results of prior proton magnetic resonance spectroscopy ( 1H-MRS) studies in unipolar major depressive disorder (MDD) evaluating choline (Cho)/creatine (Cr) and N-acetyl-L-aspartate (NAA)/Cr ratios are mixed. These single-voxel or one-dimensional chemical-shift imaging (CSI) nonautomated 1H-MRS studies has been unable to evaluate global or lateralized abnormalities in neuronal or membrane function. Using automated multivoxel two-dimensional CSI 1H-MRS techniques, we tested the hypothesis that patients with MDD have focal neuronal and membrane abnormalities localized in the subcortical region. Methods Whole brain and subcortical measures of Cho, NAA, Cr, and myo-inositol ( mI) were obtained in 18 patients with MDD and 20 control subjects using automated two-dimensional CSI 1H-MRS. Results Compared with control subjects, MDD patients had a significantly lower mean NAA/Cr amplitude in the caudate and a significantly higher mean Cho/Cr amplitude in the putamen, particularly on the right side. No differences were observed for global whole brain measurements. Conclusions The findings support reduced neuronal viability or function in the caudate and altered membrane phospholipid metabolism in the putamen for patients with MDD. Our results are consistent with prior magnetic resonance imaging, positron emission tomography, and postmortem reports of focal and lateralized abnormalities of the basal ganglia in MDD.