Quantitative Evaluation of the First Order Creatine-Kinase Reaction Rate Constant in in vivo Shunted Ovine Heart Treated with Oxandrolone Using Magnetization Transfer 31P Magnetic Resonance Spectroscopy (MT-31P-MRS) and 1H/31P Double-Tuned Surface Coil: a Preliminary Study

PURPOSE: Children born with single ventricle physiology demonstrate poor growth rate and suffer from malnutrition, which lead to increased morbidity and mortality in this population. We assume that an anabolic steroid, oxandrolone, will promote growth in these infants by improving myocardial energy utilization. The purpose of this paper is to study the efficacy of oxandrolone on myocardial energy consumption in these infants. MATERIALS AND METHODS: We modeled single ventricle physiology in a lamb by prenatally shunting the aorta to the pulmonary artery and then postnatally, we monitored cardiac energy utilization by quantitatively measuring the first order reaction rate constant, kf of the creatine-kinase reaction in the heart using magnetization transfer 31P magnetic resonance spectroscopy, home built 1H/31P transmit/receive double tuned coil, and transmit/receive switch. We also performed cine MRI to study the structure and dynamic function of the myocardium and the left ventricular chamber. The spectroscopy data were processed using home-developed python software, while cine data were analyzed using Argus software. RESULTS: We quantitatively measured both the first order reaction rate constant and ejection fraction in the control, shunted, and the oxandrolone-treated lambs. Both kf and ejection fraction were found to be more significantly reduced in the shunted lambs compared to the control lambs, and they are increased in oxandrolone-treated lambs. CONCLUSION: Some improvement was observed in both the first order reaction rate constant and ejection fraction for the lamb treated with oxandrolone in our preliminary study.

Electroacupuncture ameliorate learning and memory by improving N -acetylaspartate and glutamate metabolism in APP/PS1 mice

OBJECTIVE: To explore the precise mechanism of electroacupuncture (EA) to delay cognitive impairment in Alzheimer disease. Methods N -Acetylaspartate (NAA), glutamate (Glu) and myoinositol (mI) metabolism were measured by magnetic resonance spectroscopy, learning and memory of APP/PS1 mouse was evaluated by the Morris water maze test and the step-down avoidance test, neuron survival number and neuronal structure in the hippocampus were observed by Nissl staining, and BDNF and phosphorylated TrkB detected by Western blot. RESULTS: EA at DU20 acupuncture significantly improve learning and memory in behavioral tests, up-regulate NAA, Glu and mI metabolism, increase the surviving neurons in hippocampus, and promote the expression of BDNF and TrkB in the APP/PS1 transgenic mice. CONCLUSION: These findings suggested that EA is a potential therapeutic for ameliorate cognitive dysfunction, and it might be due to EA could improve NAA and Glu metabolism by upregulation of BDNF in APP/PS1 mice.

Molecular Neuroimaging in Posttraumatic Stress Disorder

Over the past decade, an increasing number of neuroimaging studies have provided insight into the neurobiological mechanisms of posttraumatic stress disorder (PSTD). In particular, molecular neuroimaging techniques have been employed in examining metabolic and neurochemical processes in PTSD. This article reviews molecular neuroimaging studies in PTSD and focuses on findings using three imaging modalities including positron emission tomography (PET), single photon emission computed tomography (SPECT), and magnetic resonance spectroscopy (MRS). Although there were some inconsistences in the findings, patients with PTSD showed altered cerebral metabolism and perfusion, receptor bindings, and metabolite profiles in the limbic regions, medial prefrontal cortex, and temporal cortex. Studies that have investigated brain correlates of treatment response are also reviewed. Lastly, the limitations of the molecular neuroimaging studies and potential future research directions are discussed.

Brain 1H-MRS study on the effects of copper chelation therapy on WD patients / 中国神经精神疾病杂志

Objective To examine the brain metabolic changes in WD patients receiving copper chelation by us?ing 1H-MRS. Method Thirty-nine patients with WD was randomly divided into four groups: non-brain type group (18 cases), brain type prior-treatment group and short-term treatment group (21 cases), long-term treatment group (20 cases) from short-term treatment group, and 20 healthy volunteers served as a control group. 1H-MRS and MRI were performed on patients on 1.5/MR/MRS system to detect these above-mentioned items before and after treatment. Result The mean of NAA/Cr was significantly lower in the left putamen and head of the caudate nucleus than in the left basal ganglion in the 39 patients with WD. The mean of NAA/Cr and Cho/Cr in the left putamen and basal ganglion was significantly lower in non-brain type group than in control group(P0.05). The mean of NAA/Cr and NAA/Cho in the left putamen and basal ganglion was much higher in long-term treatment group than in brain type group(P<0.01 or P<0.05). The mean of Cho/Cr in the left head of caudate nucleus were much higher after treatment compared with prior-treatment group(P<0.05). The mean of NAA/Cr in the left putamen, head of the left caudate nucleus and basal ganglion in all groups was negatively correlated with course of the disease. Conclusion There are significant differences in brain metabolism among different type of WD. The long-term but not short-term copper chelation significantly improves brain metabolism. NAA/Cr may be used as a non-invasive indicator to examine the efficacy of treatment.

H1 Magnetic Resonance Spectroscopy of Cystic Ovarian Lesions

On H1 MRS (magnetic resonance spectroscopy), malignant tumors show higher concentration of metabolite than benign lesions. Lactate double peak was detected in malignant tumor and endometriosis, and more prominent high concentration was demonstrated in endometriosis. Tuboovarian abscesses and salpingitis do not show prominent peak. Dermoid cysts show high levels of lipid peak. Paratubal cyst and follicular cyst can be showed the lipid peak, however, the concentration of lipid is lower than that of dermoid cyst. H1 MRS of ovarian cystic lesions can give valuable information about the presence of metabolites of ovarian cystic lesions.

Diferenças metabólicas no hipocampo contralateral entre pacientes concordantes e discordantes na esclerose mesial temporal (EMT): avaliação com espectroscopia de protóns por ressonância magnética (1H-ERM) / Metabolic differences in the contralateral hippocampus of concordant and discordant mesial temporal sclerosis (MTS) patients: evaluation with proton magnetic resonance spectroscopy (1H-MRS)

OBJETIVO: Pacientes com esclerose mesial temporal (EMT) são clinicamente classificados como concordantes ou discordantes de acordo com a extensão da atividade epileptogênica. O objetivo desse estudo é verificar se as alterações metabólicas no hipocampo são diferentes nos dois grupos. MATERIAIS E MÉTODOS: Foram avaliados 33 pacientes diagnosticados com EMT, 23 concordantes (33±9 anos) e 10 discordantes (33±10 anos), e 28 controles (33±10 anos). Foi obtida espectroscopia por ressonância magnética de ambos os hipocampos (ipsi e contralateral) com aparelho de 3T e com a sequência PRESS de vóxel único com TE/TR=135/1500ms. Os principais metabólitos foram quantificados com o LCModel. Para a comparação entre os grupos foram realizados testes estatísticos com nível de significância de 0,05. RESULTADOS: Para todos os pacientes foi observada redução de NAAipsi e Cr ipsi quando comparado com o lado contralateral, porém esta diferença foi significativa apenas para o grupo de pacientes concordantes. Quando comparado com o grupo controles houve uma redução significativa de Cr ipsi e NAAipsi para os dois grupos e da relação NAA/Cr ipsi para o grupo de pacientes concordantes enquanto que a relação NAA/Cr contra estava diminuída apenas no grupo de pacientes discordantes. CONCLUSÃO: Nossos achados sugerem uma maior diminuição do NAA/Cr ipsi no grupo de pacientes concordantes e da relação NAA/Cr contra no grupo de pacientes discordantes apontando para um padrão diferente de alteração metabólica para os dois grupos. Porém é preciso aumentar o tamanho da amostra para confirmar estes resultados.

PURPOSE: Patients with mesial temporal sclerosis (MTS) are clinically classified as concordant or discordant according to the extent of epileptogenic activity. The aim of this study is to determine whether the metabolic changes in the hippocampus are different in the two groups. MATERIALS AND METHODS: 33 patients diagnosed with MTS, 23 concordant (33±9 years old) and 10 discordant (33±10 years old) and 28 controls (33±10 years old) were evaluated. We obtained magnetic resonance spectroscopy of both hippocampi (ipsilateral and contralateral) on a 3T scanner with single voxel PRESS sequence with TE/TR=135/1500ms. The main metabolites were quantified with LC Model. For comparison between groups statistical tests were performed with a significance level of 0.05. RESULTS: In all patients a reduction of NAAipsi and Cr ipsi was observed, when compared to the contralateral side, but this difference was only significant for the group of concordant patients. In comparison with controls a significant reduction of Cr ipsi and NAAipsi was observed for both groups and for Naa/Cr ipsi in the group of concordant patients while NAA/Cr contra was reduced only in the group of discordant patients. CONCLUSION: Our findings suggest a stronger decline of NAA/Cr ipsi in the group of concordant patients and of NAA/Cr contra in discordant patients, suggesting a slightly different metabolic pattern for both groups. However, we need to increase the sample size to confirm these findings.

Proton magnetic resonance spectroscopy of brain in obstructive sleep apnoea in north Indian Asian subjects.

Background & objectives: Repeated apnoeic/hypoapnoeic episodes during sleep may produce cerebral damage in patients with obstructive sleep apnoea (OSA). The aim of this study was to determine the absolute concentration of cerebral metabolites in apnoeic and non-apnoeic subjects from different regions of the brain to monitor the regional variation of cerebral metabolites. Methods: Absolute concentration of cerebral metabolites was determined by using early morning proton magnetic resonance spectroscopy (1H MRS) in 18 apnoeic patients with OSA (apnoeics) having apnoea/hypopnoea index (AHI) >5/h, while 32 were non-apnoeic subjects with AHI< 5/h. Results: The absolute concentration of tNAA [(N-acetylaspartate (NAA)+N-acetylaspartylglutamate (NAAG)] was observed to be statistically significantly lower (P<0.05) in apnoeics in the left temporal and left frontal gray regions compared to non-apnoeics. The Glx (glutamine, Gln + glutamate, Glu) resonance showed higher concentration (but not statistically significant) in the left temporal and left frontal regions of the brain in apnoeics compared to non-apnoeics. The absolute concentration of myo-inositol (mI) was significantly high (P<0.03) in apnoeics in the occipital region compared to non-apnoeics. Interpretation & conclusions: Reduction in the absolute concentration of tNAA in apnoeics is suggestive of neuronal damage, probably caused by repeated apnoeic episodes in these patients. NAA showed negative correlation with AHI in the left frontal region, while Cho and mI were positively correlated in the occipital region and Glx showed positive correlation in the left temporal region of the brain. Overall, our results demonstrate that the variation in metabolites concentrations is not uniform across various regions of the brain studied in patients with OSA. Further studies with a large cohort of patients to substantiate these observations are required.

MR Images and 1H MR Spectroscopy of Enteric Duplication Cyst of the Pancreas in an Adult

Enteric duplications associated with the pancreas are especially uncommon, and the differential diagnosis of pancreatic duplication cysts is often difficult, and may be confused with various cystic lesions of the pancreas. We report a case of pancreatic duplication cyst; present the images and laboratory findings including cyst fluid tumor markers. MR and MRS findings enabled the detection of the location, contour, characteristics of cystic fluid and definition of tissue planes between the lesion and adjacent structures, providing useful information for an accurate surgical approach.

Numerical Design of Double Quantum Coherence Filter for the Detection of Myo-Inositol In vivo

PURPOSE: A numerical method of designing a multiple quantum filter (MQF) is presented for the optimum detection of myo-inositol (mI), an important brain metabolite, by using in vivo proton nuclear magnetic resonance spectroscopy ((1)HMRS). MATERIALS AND METHODS: Starting from the characterization of the metabolite, the filter design includes the optimization of the sequence parameters such as the two echo times (TEs), the mixing time (TM), and the flip angle and offset frequency of the 3rd 90 degrees pulse which converts multiple quantum coherences (MQCs) back into single quantum coherences (SQCs). The optimized filter was then tested both in phantom and in human brains. RESULTS: The results demonstrate that the proposed MQF can improve the signal-tobackground ratio of the target metabolite by a factor of more than three by effectively suppressing the signal from the background metabolites. CONCLUSION: By incorporating a numerical method into the design of MQFs in 1HMRS the spectral integrity of a target metabolite, in particular, with a complicated spin system can be substantially enhanced.

Evaluations of Spectral Analysis of in vitro 2D-COSY and 2D-NOESY on Human Brain Metabolites

PURPOSE: To investigate the 3-bond and spatial connectivity of human brain metabolites by scalar coupling and dipolar nuclear Overhauser effect/enhancement (NOE) interaction through 2D- correlation spectroscopy (COSY) and 2D- NOE spectroscopy (NOESY) techniques. MATERIALS AND METHODS: All 2D experiments were performed on Bruker Avance 500 (11.8 T) with the zshield gradient triple resonance cryoprobe at 298 K. Human brain metabolites were prepared with 10% D2O. Two-dimensional spectra with 2048 data points contains 320 free induction decay (FID) averaging. Repetition delay was 2 sec. The Top Spin 2.0 software was used for post-processing. Total 7 metabolites such as N-acetyl aspartate (NAA), creatine (Cr), choline (Cho), glutamine (Gln), glutamate (Glu), myo-inositol (Ins), and lactate (Lac) were included for major target metabolites. RESULTS: Symmetrical 2D-COSY and 2D-NOESY spectra were successfully acquired: COSY cross peaks were observed in the only 1.0-4.5 ppm, however, NOESY cross peaks were observed in the 1.0-4.5 ppm and 7.9 ppm. From the result of the 2-D COSY data, cross peaks between the methyl protons (CH3(3)) at 1.33 ppm and methine proton (CH(2)) at 4.11 ppm were observed in Lac. Cross peaks between the methylene protons (CH2(3,H alpha)) at 2.50ppm and methylene protons (CH2,(3,HB)) at 2.70 ppm were observed in NAA. Cross peaks between the methine proton (CH(5)) at 3.27 ppm and the methine proton (CH(4,6)) at 3.59 ppm, between the methine proton (CH(1,3)) at 3.53 ppm and methine proton (CH(4,6)) at 3.59 ppm, and between the methine proton (CH(1,3)) at 3.53 ppm and methine proton (CH(2)) at 4.05 ppm were observed in Ins. From the result of 2-D NOESY data, cross peaks between the NH proton at 8.00 ppm and methyl protons (CH3) were observed in NAA. Cross peaks between the methyl protons (CH3(3)) at 1.33 ppm and methine proton (CH(2)) at 4.11 ppm were observed in Lac. Cross peaks between the methyl protons (CH3) at 3.03 ppm and methylene protons (CH2) at 3.93 ppm were observed in Cr. Cross peaks between the methylene protons (CH2(3)) at 2.11 ppm and methylene protons (CH2(4)) at 2.35 ppm, and between the methylene protons(CH2 (3)) at 2.11 ppm and methine proton (CH(2)) at 3.76 ppm were observed in Glu. Cross peaks between the methylene protons (CH2 (3)) at 2.14 ppm and methine proton (CH(2)) at 3.79 ppm were observed in Gln. Cross peaks between the methine proton (CH(5)) at 3.27 ppm and the methine proton (CH(4,6)) at 3.59 ppm, and between the methine proton (CH(1,3)) at 3.53 ppm and methine proton (CH(2)) at 4.05 ppm were observed in Ins. CONCLUSION: The present study demonstrated that in vitro 2D-COSY and NOESY represented the 3-bond and spatial connectivity of human brain metabolites by scalar coupling and dipolar NOE interaction. This study could aid in better understanding the interactions between human brain metabolites in vivo 2DCOSY study.

Evaluation of Antidepressant Drug Effect in a Depressive Animal Model by Proton MR Spectroscopy / 의학물리

In this study, we observed the alteration of choline signal intensity in hippocampus region of the depressive rat model induced by forced swimming test (FST). The purpose of this study was to evaluate the antidepressant efficacy in the depressive animal model using MR spectroscopy. Fourteen experimentally naive male Sprague-Dawley rats weighting 160~180 g were used as subjects. Drug injection group was exposed to the FST except for control group. The drugs were administered subcutaneously (SC) in a volume equivalent to 2 ml/kg. And three injections were administered 23, 5, and 1 h before beginning the given test. 1H MR spectra were obtained with use of a point resolved spectroscopy (PRESS) localization sequence performed according to the following parameters: repetition time, 2500 ms; echo time, 144 ms; 512 average; 2048 complex data points; voxel dimensions, 1.5x2.5x2.5 mm3; acquisition time, 25 min. There were no differences in NAA/Cr and Cho/Cr ratio between the right and the left hippocampus both normal control rats and antidepressant-injected rats. Also, no differences were observed in NAA/Cr and Cho/Cr ratio between the normal control rats and the antidepressant-injected rats both the right and the left hippocampus. In this study, we found the recovery of choline signals in the depressive animal model similar to normal control groups as injecting desipramine-HCl which was antidepressant causing anti-immobility effects. Thus, we demonstrated that MR spectroscopy was able to aid in evaluating the antidepressant effect of desipramine-HCl.

Alteration Analysis of Normal Human Brain Metabolites with Variation of SENSE and NEX in 3T Multi Voxel Spectroscopy / 의학물리

To evaluate the metabolic changes in normal adult brains due to alterations SENSE and NEX (number of excitation) by multi voxel MR Spectroscopy at 3.0 Tesla. The study group was composed of normal volunteers (5 men and 8 women) with a mean (+/- standard deviation) age of 41 (+/-11.65). Their ages ranged from 28 to 61 years. MR Spectroscopy was performed with a 3.0T Achieva Release Version 2.0 (Philips Medical System-Netherlands). The 8 channel head coil was employed for MRS acquisition. The 13 volunteers underwent multi voxel spectroscopy (MVS) and single voxel spectroscopy (SVS) on the thalamus area with normally gray matter. Spectral parameters were as follows: 15 mm of thickness; 230 mm of FOV (field of view); 2000 msecs of repetition time (TR); 288 msecs of echo time (TE); 110x110 mm of VOI (view of interest); 15x15x15 mm of voxel size. Multi voxel spectral parameters were made using specially in alteration of SENSE factor (1~3) and 1~2 of NEX. All MRS data were processed by the jMRUI 3.0 Version. There was no significant difference in NAA/Cr and Cho/Cr ratio between MVS and SVS likewise the previous results by Ross and coworkers in 1994. In addition, despite the alterations of SENSE factor and NEX in MVS, the metabolite ratios were not changed (F-value : 1.37, D.F : 3, P-value : 0.262). However, line-width of NAA peak in MVS was 3 times bigger than that in SVS. In the present study, we demonstrated that the alterations of SENSE factor and NEX were not critically affective to the result of metabolic ratios in the normal brain tissue.

Investigation of Varied MR Spectra by TE and Metabolite Amount in the Localized Voxel using the MR Cone-shape Phantom / 의학물리

The purpose of this study is to investigate the spectra of a magnetic resonance spectroscopy (MRS) in accordance with the variance of TE and the volumes of metabolites in a localized voxel for the quality assurance using a designed single voxel spectroscopy QA phantom. Because a cone-shape phantom is designed as the volume of metabolite in a localized voxel is changeable, we try to analyze the peaks of each metabolite (NAA, Cr, Cho, Lac, etc.) in accordance with metabolite volume in a localized voxel as well as echo time (TE). All data were obtained using a 3T MRI/MRS machine and analyzed using jMRUI(R). The results of this study show that TE is in inverse proportion to the noise of MRS and the longer TE and the less metabolite volume in the localized voxel, the peak intensities of each metabolite decrease. In case of the lactate, its peak was observed on the all TE only if the greatest metabolite is included in the localized voxel. Then, the intensity of a metabolite is more sensitive to the metabolite volume in the localized voxel than the TE. These obtained in vitro MRS data is provide the guideline that is important for in vivo metabolite quantification. But, in the edge of cone-shape vial air bubbles were observed and spectrum could not obtained. Therefore our cone-shape MRS phantom needs to be modified in order to solve these problems.

Effect of Yinaotongluo Capsule on diffuse weighting image and energy metabolism of ischemia-reperfused rats / 中国康复理论与实践

@#ObjectiveTo explore the effect of Yinaotongluo Capsule on diffuse weighting image and enenery metabolism of ischemia-reperfuing rat.MethodsMagnetic resonance diffusion-weighted imaging(DWI) and 1H and magnetic resonance spectroscopy(MRS) were performed in different brain regions in focal cerebral ischemic-reperfusion injury model rats. ResultsYinaotongluo Capsule could significantly reduce the area and the intensity of infarction of rats by DWI 3 h and 5 d after treatment compared with the model group.The result of 1H MRS examination demonstrated Lac peak was lower and NAA peak higher than that of the model group. ConclusionYinaotongluo Capsule can effectually improve enenery metabolism during cerebral ischemia and reperfuing, so that to reduce the neuronal dysfunction and death in infarcts at the late stage.

The Change of Cerebral Metabolites in Patients with Parkinson's Disease Measured by Proton Magnetic Resonance Spectroscopy

BACKGROUND: Parkinson's disease is a progressive, common neuro-degenerative disorder of the extrapyramidal system leading to specific motor symptoms, but there is no specific early diagnostic tool. This study was aimed to investigate the change of cerebral metabolites in patients with parkinson's disease by 1H magnetic resonance spectroscopy (MRS). METHODS: Eighteen patients with idiopathic unilateral symptomatic parkinson's disease underwent MRS study to compare metabolites of basal ganglia and thalamus, in ipsilateral and contralateral to the clinically affected side. RESULTS: In patients with unilateral symptomatic parkinson's disease, N-acetyl aspartate (NAA)/Creatine (Cr) ratio was significantly lower in contralateral side to the clinically affected side than in ipsilateral side (p=0.023). Other cerebral metabolites (Cho, mI, alpha-Glx, beta-Glx, lactate, lipid) were showed no significant difference in patients with parkinson's disease. CONCLUSIONS: The comparison and quantification of cerebral metabolites by using MRS may be helpful to diagnosis and investigation of parkinson's disease.

Ex Vivo 1H MR Spectroscopy: Normal gastric and cancer tissue

PURPOSE: In this study, we attempted to ascertain the proton magnetic resonance spectroscopy (1H MRS) peak characteristics of human gastric tissue layers and finally to use the metabolic peaks of MRS to distinguish between normal and abnormal gastric specimens. MATENRIALS AND METHODS: Ex-vivo 1H MRS examinations of thirty-five gastric specimens were performed to distinguish abnormal gastric tissues invaded by carcinoma cells from normal stomach-wall tissues. High-resolution 400-MHz (9.4-T) 1H nuclear magnetic resonance (NMR) spectra of two gastric layers, a proper muscle layer, and a composite mucosa- submucosa layer were compared with those of clinical 64- MHz (1.5-T) MR spectra. Three-dimensional spoiled gradient recalled (SPGR) images were used to determine the size and the position of a voxel for MRS data collection. RESULTS: For normal gastric tissue layers, the metabolite peaks of 400-MHz 1H MRS were primarily found to be as follows: lipids at 0.9 ppm and 1.3 ppm; alanine at 1.58 ppm; N-acetyl neuraminic acid (sialic acid) at 2.03 ppm; and glutathione at 2.25 ppm in common. The broad and feature-less spectral peaks of the 64-MHz MRS were bunched near 0.9, 1.3, and 2.0, and 2.2 ppm in human specimens without respect to layers. In a specimen (Borrmmann type III) with a tubular adenocarcinoma, the resonance peaks were measured at 1.26, 1.36 and 3.22 ppm. All the peak intensities of the spectrum of the normal gastric tissue were reduced, but for gastric tumor tissue layers, the lactate peak split into 1.26 and 1.39 ppm, and the peak intensity of choline at 3.21 ppm was increased. CONCLUSION: We found that decreasing lipids, an increasing lactate peak that split into two peaks, 1.26 ppm and 1.36 ppm, and an increasing choline peak at 3.22 ppm were markers of tumor invasion into the gastric tissue layers. This study implies that MR spectroscopy can be a useful diagnostic tool for gastric cancer.

Ex Vivo 1H MR Spectroscopy: Normal gastric and cancer tissue

PURPOSE: In this study, we attempted to ascertain the proton magnetic resonance spectroscopy (1H MRS) peak characteristics of human gastric tissue layers and finally to use the metabolic peaks of MRS to distinguish between normal and abnormal gastric specimens. MATENRIALS AND METHODS: Ex-vivo 1H MRS examinations of thirty-five gastric specimens were performed to distinguish abnormal gastric tissues invaded by carcinoma cells from normal stomach-wall tissues. High-resolution 400-MHz (9.4-T) 1H nuclear magnetic resonance (NMR) spectra of two gastric layers, a proper muscle layer, and a composite mucosa- submucosa layer were compared with those of clinical 64- MHz (1.5-T) MR spectra. Three-dimensional spoiled gradient recalled (SPGR) images were used to determine the size and the position of a voxel for MRS data collection. RESULTS: For normal gastric tissue layers, the metabolite peaks of 400-MHz 1H MRS were primarily found to be as follows: lipids at 0.9 ppm and 1.3 ppm; alanine at 1.58 ppm; N-acetyl neuraminic acid (sialic acid) at 2.03 ppm; and glutathione at 2.25 ppm in common. The broad and feature-less spectral peaks of the 64-MHz MRS were bunched near 0.9, 1.3, and 2.0, and 2.2 ppm in human specimens without respect to layers. In a specimen (Borrmmann type III) with a tubular adenocarcinoma, the resonance peaks were measured at 1.26, 1.36 and 3.22 ppm. All the peak intensities of the spectrum of the normal gastric tissue were reduced, but for gastric tumor tissue layers, the lactate peak split into 1.26 and 1.39 ppm, and the peak intensity of choline at 3.21 ppm was increased. CONCLUSION: We found that decreasing lipids, an increasing lactate peak that split into two peaks, 1.26 ppm and 1.36 ppm, and an increasing choline peak at 3.22 ppm were markers of tumor invasion into the gastric tissue layers. This study implies that MR spectroscopy can be a useful diagnostic tool for gastric cancer.

CT 、MRI and~1H-MRS Diagnosis of Central Neurocytoma:A Report of 7 Cases with Literature Review / 实用放射学杂志

Objective To discuss CT,MR and~1H-MRS features of central neurocytoma(CNC).Methods Imaging findings ofneurocytomas in 7 cases confirmed by pathology were retrospectively analyzed with literature review.2 cases were examined by CT、MR and~1 H-MRS,2 cases only by MR,and 3 cases only by CT.Results All the tumors were located in the lateral ventricles.There were different degree hydrocephalus in all cases.The masses were heterogeneous appearance on CT with necrotic area and fine to course calcifications.Heterogeneous enhancement was seen in the solid portion.The tumors were isointense and hypointense on T_1WI and heterogeneous on T_2WI.Heterogeneous enhancement was also seen on MRI.The in vivo~1H-MRS showed prominent choline(Cho) and low N-acetyl aspartate(NAA) compared to the normal.Conclusion Central neurocytoma should be considered when a tumor was located at the lateral ventricles especially septum pellucidum in young patients.CT,MR and~1H-MRS are helpful in making a preoperative diagnosis.

Proton Magnetic Resonance Spectroscopy in Patients with Neuro-Behcet's Disease / 대한류마티스학회지

Magnetic resonance imaging (MRI)and computed tomography had been used to detect the neurologic lesions of the Behcet's disease.However,there are a number of cases which can not be detected by conventional imaging studies in neuro-Behcet's disease.To overcome this problem,magnetic resonance spectroscopy (MRS)has been introduced in several autoimmune diseases involving central nervous system such as neuropsychiatric lupus,but which was rarely performed in Behcet's disease.In the present study,we report two cases of neuro-Behcet's disease that showed normal MRI but abnormal proton MRS (1HMRS)findings.MRS in two cases revealed a reduction of the N-acetyl aspartate (NAA)/creatine (Cr)ratio in the substantia nigra and thalamus,respectively, which were the areas without abnormality on MRI,suggesting a functional defect of neurons in these areas.In a case with thalamic dysfunction,abnormal NAA/Cr ratio was normalized in parallel with clinical improvement after treatment with high-dose steroids and immuno-suppressive agents.These observa-tions suggest that MRS may be useful to early detect the functional abnormality in neuro-Behcet's disease and to monitor neurologic status after treatment with immuno-suppressive agents.

A Case of Korean Patient with Noketotic Hyperglycinemia: Diagnosed Based on CSF Amino Acid Analysis and Magnetic Resonance Spectroscopy

Nonketotic hyperglycinemia is an extremely rare congenital metabolic disorder, which is caused by the lack of a glycine cleavage system. The onset of hyperglycinemic symptom is during the neonatal or early infant period. Progressing grave neuromotor dysfunction is one of the main symptoms. They include myoclonic seizure, hiccup, apnea, decreased deep tendon reflex, lethargy and coma. The prognosis is mostly very poor. Furtherrnore, there aren't any effective treatments for nonketotic hyperglycinemia. To our knowledge, there has been no reported case of nonketotic hyperglycinemia in Korea. We experienced a case of nonketotic hyperglycinemia in a three-day- old boy, who had manifested with intractable seizure, mental alteration, apnea, hiccup and feeding intolerance. Unfortunately, he died of intractable seizure and neuromotor dysfunction at 20 days after birth. We could make an early diagnosis on the basis of clinical suspicion and high glycine signal in both cerebral white matter and basal ganglias with magnetic resonance spectroscopy (MRS), before amino acid analyses of serum and cerebrospinal fluid(CSF) were obtained. We report a Korean case of nonketotic hyperglycinemia with a brief review of literatures.