帕金森病患者不同脑区质子磁共振波谱研究

目的:探讨~1H-MRS对早期PD的诊断价值。方法:采用~1H-MRS技术检测早期PD、晚期PD、帕金森综合征、偏侧ET以及年龄匹配的正常对照组基底节区和皮质运动区感兴趣区的NAA/Cr和Cho/Cr比值。结果:早期或晚期PD、偏侧ET及帕金森综合征患者受累较重基底节区或运动皮质区NAA/Cr及Cho/Cr比值与受累较轻侧相比无显著性差异;上述各组患者受累较重基底节区或运动皮质区NAA/Cr及Cho/Cr比值与正常对照组相应感兴趣区NAA/Cr及Cho/Cr比值相比也均无显著性差异。结论:~1H-MRS无助于早期PD的诊断。     

Metabolic changes in 37 newly diagnosed Wilson's disease patients assessed by magnetic resonance spectroscopy

Wilson's Disease (WD) is a rare autosomal recessive disorder. The literature about proton MR spectroscopy (MRS) in WD is based mostly on data derived from patients undergoing treatment. The aim of this study was to identify brain metabolic changes in newly diagnosed WD patients using MRS to elucidate the pathomechanism of the cerebral pathology of WD. The globus pallidus and thalamus of 37 patients with WD were examined bilaterally with MRS. The calculations were performed for: myoinositol (mI), choline (Cho), creatine (Cr), N-acetyl-aspartate (NAA), lipid (Lip), glutamine, and glutamate (Glx). In all WD patients a significantly decreased mI/Cr and NAA/Cr ratio levels and an increased Lip/Cr ratio in the pallidum were observed. Analysis revealed a significantly increased Glx/Cr and Lip/Cr ratio in the thalamus. In the pallidum of neurologically impaired patients, Cho/Cr, Glx/Cr and Lip/Cr ratios were higher than in control subjects, and the NAA/Cr was significantly lower. In hepatic patients, the mI/Cr, Cho/Cr and NAA/Cr ratio levels were lower than in controls. The Cho/Cr and Lip/Cr ratios were higher in the thalami of neurologically impaired patients, and Lip/Cr ratios were higher than controls' in hepatic patients. Both findings were statistically significant. Compared to the thalamus, the basal ganglia are more sensitive to ongoing degenerative changes and portal-systemic encephalopathy in WD. The NAA/Cr reduction in hepatic and neurologically impaired patients could indicate that neurodegeneration is associated with all presentations of WD. In hepatic patients a mI and Cho decrease and in neurological Glx increase can be caused by porto-systemic shunting.     

Neurochemical alterations of the brain in bipolar disorder and their implications for pathophysiology: a systematic review of the in vivo proton magnetic resonance spectroscopy findings

OBJECTIVE: To perform systematic analysis of current proton magnetic resonance spectroscopy ((1)H MRS) findings in bipolar disorder (BD). METHOD: We grouped the (1)H MRS studies documenting data on the metabolites of N-acetylaspartate (NAA), Choline (Cho), myo-inositol (mI), Glutamate (Glu)/Glutamine (Gln) and Creatine (Cr) separately, for each of the euthymic, manic, depressed adult and child/adolescent bipolar patients. RESULTS: For NAA resonance, 22 studies involving 328 adult bipolar and 349 control subjects were identified. NAA levels were lower in euthymic bipolar patients in the frontal lobe structures and hippocampus. Lithium seems to have an increasing effect on NAA in those brain regions. Available data in children indicates lower NAA levels in euthymic bipolar patients in dorsolateral prefrontal cortex (DLPFC) and cerebellar vermis. Existing data over 25 studies on 366 adult bipolar and 393 control subjects, although inconsistent, may suggest higher Cho/Cr ratios in the basal ganglia (BG) of euthymic bipolar patients. The metabolite mI seems to be increased both in euthymic and manic bipolar children, while most of the available data does not support such alteration in adults. Glu/Gln levels in adult bipolar patients were higher in all mood states compared to controls. Limited data in children supports such an alteration only in the euthymic state. CONCLUSION: The studies reviewed in this paper suggest regional abnormalities of NAA, Cho and Glu/Gln in BD, with the DLPFC, prefrontal and anterior cingulate cortices, hippocampus, and BG being specifically implicated. Systematic analysis of (1)H MRS findings so far helps to define future strategies in this field for delineation of actual neurochemical framework in BD.     

Proton magnetic resonance spectroscopy of the frontal lobe and cerebellar vermis in children with a mood disorder and a familial risk for bipolar disorders

OBJECTIVE: Few studies have examined the neurochemical abnormalities that might be associated with pediatric bipolar disorder. The aim of this study was to use magnetic resonance spectroscopy to evaluate several brain regions implicated in bipolar disorder in children with a mood disorder and a familial risk for bipolar disorder. We hypothesized that these children would exhibit neurochemical differences compared with healthy children of parents without a psychiatric disorder. Specifically, decreased N-acetylaspartate (NAA) and creatine and phosphocreatine (Cr) of the prefrontal cortex and cerebellar vermis would reflect impairments in neuronal function and cellular metabolism, and elevated myo-inositol (mI) would reflect impaired phosphoinositide metabolism, potentially representing early markers of neurophysiologic changes that might underlie the development of bipolar disorder. METHODS: Children with a mood disorder and at least one parent with bipolar disorder (n = 9) and healthy children (n = 10) group matched for age (8-12 years), race, sex, education, and Tanner stage were evaluated using the Washington University in St. Louis Kiddie Schedule for Affective Disorders and Schizophrenia. Proton magnetic resonance spectroscopy was acquired using 8-cc volumes within the frontal cortex, frontal white matter, and the cerebellar vermis. Metabolite ratios (NAA/Cr, cholines (Cho)/Cr, mI/Cr, NAA/Cho, NAA/mI, and Cho/mI) and concentrations (NAA, Cr, Cho, and mI) were calculated and compared between groups. RESULTS: The trend in concentration levels of NAA and Cr was approximately 8% lower for children with a mood disorder than healthy children within the cerebellar vermis. The frontal cortex in children with a mood disorder revealed elevated mI concentration levels, approximately 16% increased, compared with healthy children. CONCLUSIONS: Similar to findings in adults with bipolar disorders, neurochemical abnormalities within the frontal cortex and the cerebellar vermis were present in this preliminary comparison of children with a mood disorder and a familial risk for bipolar disorder. Larger sample sizes are needed to replicate these findings.     

Proton magnetic resonance spectroscopy study of dyskinesia patients.

Oral dyskinesias may occur spontaneously or be induced by medications such as antipsychotics and antidepressants. In this study, single voxel proton magnetic resonance spectroscopy was used to compare metabolite levels in the striatum for (1) 12 patients with drug-induced tardive dyskinesia (TD), (2) 12 patients with spontaneous oral dyskinesia (SOD), (3) 8 antidepressant-treated patients without TD, and (4) 8 control subjects. Statistically significant reductions in the choline/creatine (Cho/Cr) ratio were measured for the drug-treated patients with TD (-13%, P = 0.020) and SOD patients (-12%, P = 0.034) relative to control subjects. In comparison with antidepressant-treated patients without TD, drug-treated patients with TD showed a non statistically significant reduction in Cho/Cr (-11%, P = 0.079). All other metabolite ratios (N-acetylaspartate (NAA)/Cr, myo-inositol (mI)/Cr, glutamine + glutamate (Glx)/Cr, macromolecule + lipid (MM+Lip)/Cr, NAA/Cho) were unaffected by either type of dyskinesia. The observed Cho/Cr reduction in dyskinesia patients suggests decreased membrane phosphatidylcholine turnover, which provides free choline as precursor of molecules responsible for cellular signal transduction.     

Single voxel proton magnetic resonance spectroscopy in women with and without intimate partner violence-related posttraumatic stress disorder

Preliminary in vivo proton magnetic spectroscopic ((1)H-MRS) studies of N-acetylaspartate (a putative marker of neuronal viability and function) in combat veterans and maltreated children with posttraumatic stress disorder (PTSD) suggest altered neuronal integrity in anterior cingulate and medial temporal lobe structures. In this study, (1)H-MRS was used to measure N-acetylaspartate (NAA), choline (Cho) and myo-inositol (mI) relative to creatine (Cr) in the anterior cingulate of 16 women with histories of intimate partner violence (7 with a DSM-IV diagnosis of PTSD, 9 without PTSD) and 11 healthy, non-abused comparison subjects. The relationship between anterior cingulate chemistry and performance on the Stroop Color-Word task and Part B of the Trail Making Test was also examined. There were no significant differences in anterior cingulate or occipital gray matter metabolite ratios of NAA/Cr and Cho/Cr between intimate partner violence and healthy comparison subjects. Intimate partner violence subjects with PTSD had significantly higher anterior cingulate Cho/Cr than intimate partner violence subjects without PTSD. There was evidence that the subjects with PTSD suffered more severe intimate partner violence as measured by the Conflict Tactics Scale-Revised. Metabolite ratios were not significantly correlated with performance on the Stroop or Trails B. Our findings, in agreement with earlier studies, showed significant alterations in anterior cingulate chemistry in women with PTSD. In contrast to other studies, we found an increase in Cho/Cr rather than a decrease in NAA/Cr, indicating alterations in glia, instead of neuronal dropout.     

急性脑梗死患者脑组织磁共振波谱研究

目的研究基底节区急性脑梗死患者脑组织磁共振波谱(MRS)的改变。方法应用MRS检测50例一侧基底节区梗死患者(脑梗死组)及50例其他疾病患者(对照组)双侧基底节区的N-乙酰天冬氨酸(NAA)、胆碱复合物(Cho)、肌酸复合物(Cr)和乳酸(Lac)水平及NAA/Cr、Cho/Cr比值。结果脑梗死组病灶侧Cho及Cr水平均显著低于非病灶侧(均P<0.05),NAA、Lac水平及NAA/Cr、Cho/Cr比值的差异无统计学意义。脑梗死组病灶侧及非病灶侧Cho、NAA及Cr水平均明显低于对照组病灶对应区(P<0.001～0.05),而Lac水平明显高于对照组病灶对应区(均P<0.05)。与对照组病灶对应区比较,脑梗死组病灶侧Cho/Cr比值显著升高,非病灶侧NAA/Cr比值显著降低(均P<0.05)。结论基底节区梗死急性期病灶侧及对侧脑组织均有明显的代谢障碍,且病灶区代谢异常较对侧更明显。     

Gray and white matter brain chemistry in young children with autism

CONTEXT: The brain pathophysiological abnormalities underlying autism remain unclear. Neuroimaging and histological studies suggest cellular abnormalities early in the course of the disease. OBJECTIVE: To measure the in vivo chemical profile of gray and white matter tissues in autism. DESIGN: Cross-sectional spectroscopic imaging study comparing 3- to 4-year-old children with autism spectrum disorder (ASD) with age-matched comparison groups of children with delayed development (DD) and typical development (TD). SETTING: The University of Washington Diagnostic Imaging Sciences Center, Seattle. PARTICIPANTS: Forty-five 3- to 4-year-old children with ASD, 12 age-matched children with DD, and 10 age-matched children with TD. MAIN OUTCOME MEASURES: Estimates of gray and white matter concentrations for choline-containing compounds (Cho), creatine plus phosphocreatine, N-acetylaspartate (NAA), and myo-inositol (mI). Transverse relaxation times for Cho, creatine plus phosphocreatine, and NAA expressed relative to control subjects with TD were examined to evaluate tissue compactness. RESULTS: The children with ASD demonstrated decreased gray matter concentrations of Cho (P < .001), creatine plus phosphocreatine (P = .02), NAA (P = .02), and mI (P = .008) compared with children with TD. Gray matter Cho transverse relaxation was also prolonged for the ASD sample compared with the TD group (P = .01). The children with ASD demonstrated significantly decreased levels of Cho (P = .04) and mI (P = .008) and trend-level NAA (P = .09) in gray matter compared with the DD group. For white matter, both children with ASD and children with DD showed a similar pattern of NAA and mI level decreases (for children with ASD vs children with TD: NAA, P = .03; mI, P = .04; for children with DD vs children with TD, NAA, P = .03; mI, P = .07). In several analyses, cerebral volume contributed significantly as a covariate. CONCLUSIONS: Reduced gray matter chemical concentrations and altered Cho transverse relaxation, in a pattern distinct from that in children with DD, suggest decreased cellularity, or density, at this early time point in ASD. Possibly reflecting shared developmental features, white matter results were common to ASD and DD groups. The relationship between cerebral volume and neurochemistry at this early time point may indicate processes related to unit scaling.     

Proton magnetic resonance spectroscopy (1H-MRS) of the thalamus in schizophrenia.

This study applied (1)H-MRS in the thalamus of schizophrenic patients and healthy subjects. There were no differences in the metabolite ratios (NAA/Cr, Cho/Cr or mI/Cr) between the two groups. Relationships were noted between NAA/Cr and age in patients with a trend toward this correlation in controls, suggesting an effect of age on the metabolism of the thalamus.     

Review of 1H magnetic resonance spectroscopy findings in major depressive disorder: a meta-analysis

In a review of the current literature, we identified (1)H MRS studies of major depressive disorder (MDD) that examined the metabolites N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), glutamate/glutamine/gamma-aminobutyric acid-GABA (Glx), and creatine (Cr). Separate meta-analyses comparing adult and pediatric MDD patients with healthy controls were performed. For adults, 14 studies with 227 patients/246 controls for NAA, 15 studies with 240 patients/261 controls for Cho, seven studies with 96 patients/104 controls for mI, six studies with 86 patients/109 controls for Glx, and nine studies with 146 patients/173 controls for Cr were identified. There were six studies containing a total of 79 pediatric depressed patients. We performed 15 separate meta-analyses to combine results from studies with similar characteristics. Adult MDD patients had higher Cho/Cr values than controls in the basal ganglia. In contrast, three studies on Glx levels indicated significantly lower Glx levels in the frontal lobe of MDD patients. The review indicated increased Cho/Cr in the basal ganglia in MDD and no alteration of NAA, suggesting an increased membrane turnover in MDD without a neurodegenerative outcome. Lower Glx levels in depressed patients in contrast to a likely hyperglutamatergic state in bipolar disorder may implicate a different pathophysiological ground in MDD.     

Differences between attention-deficit disorder with and without hyperactivity: a 1H-magnetic resonance spectroscopy study

Using proton magnetic resonance spectroscopy ((1)H-MRS) to investigate possible neurometabolic differences between the predominantly inattentive subtype (ADHD-I), the combined subtype (ADHD-C) and normal controls. Proton spectra were acquired bilaterally on the lenticular nucleus in 20 schoolboys having ADHD and 10 matched controls. The boys with ADHD were divided into ADHD-C subtype (n=10) and ADHD-I subtype (n=10) according to DSM-IV criteria. The peaks of N-acetylaspartate (NAA), Choline moieties (Cho), myo-inositol (mI), creatine (Cr) and alpha-Glx were measured and their ratios to Cr were calculated. One-way ANOVA and post-hoc Bonferroni tests were used to detect the difference of the peak-area ratios of NAA, Cho, mI, and alpha-Glx to Cr among the three groups. There was a significant overall group difference in the NAA/Cr ratio both in the right and left lenticular nucleus (right: P=0.002; left: P=0.003). Only the ADHD-C subtype group showed a significant difference with controls (right: P=0.001; left: P=0.003) the right lenticular nucleus, the NAA/Cr ratio in the ADHD-C group was significantly lower than that in the ADHD-I group (P=0.012). In the left lenticular nucleus, the NAA/Cr ratio in the ADHD-C group showed a significant trend compared to the ADHD-I group (P=0.06). This study demonstrated the existence of measurable difference between children with ADHD-C and ADHD-I using (1)H-MRS.     

Effects of Alzheimer disease on fronto-parietal brain N-acetyl aspartate and myo-inositol using magnetic resonance spectroscopic imaging

Previous magnetic resonance (MR) spectroscopy studies of Alzheimer disease (AD) reporting reduced N-acetyl aspartate (NAA) and increased myo-Inositol (mI) used single voxel techniques, which have limited ability to assess the regional distribution of the metabolite abnormalities. The objective of this study was to determine the regional distribution of NAA and mI alterations in AD by using MR spectroscopic imaging. Fourteen patients with AD and 22 cognitively normal elderly were studied using structural MR imaging and MR spectroscopic imaging. Changes of NAA, mI, and various metabolite ratios were measured in frontal and parietal lobe gray matter (GM) and white matter. This study found: (1) when compared with cognitively normal subjects, AD patients had increased mI and mI/creatine (Cr) ratios primarily in parietal lobe GM, whereas frontal lobe GM and white matter were spared; (2) in the same region where mI was increased, AD patients had also decreased NAA and NAA/Cr ratios, replicating previous findings; (3) however, increased mI or mI/Cr ratios did not correlate with decreased NAA or NAA/Cr ratios; and (4) using mI/Cr and NAA/Cr together improved sensitivity and specificity to AD from control as compared with NAA/Cr alone. In conclusion, decreased NAA and increased mI in AD are primarily localized in parietal lobe GM regions. However, the NAA and mI changes are not correlated with each other, suggesting that they represent different processes that might help staging of AD.     

Longitudinal metabolic and cognitive changes in mild cognitive impairment patients

Advancements in clinical therapies have identified the need for biomarkers of early Alzheimer disease that distinguish the earliest stages of pathology and target those patients who are likely to gain the most benefit. The aim of this study was to characterize the longitudinal metabolic changes measured by 1H magnetic resonance spectroscopy in correlation to neuropsychologic indices of episodic memory, attention and mental processing speed, language facility, and executive function in subjects with mild cognitive impairment (MCI). Quantitative 1H magnetic resonance spectroscopy of the posterior cingulate gyrus was performed and repeated at 11.56+/-4.3 months. N-acetyl aspartate (NAA), total choline (Cho), total creatine (Cr), myo-inositol (mI), and glutamate/glutamine (Glx) metabolite levels were measured, corrected for cerebrospinal fluid dilution, and ratios calculated in MCI and cognitively normal subjects. In the first study, MCI subjects showed lower NAA levels, NAA/Cho, and NAA/mI ratios and increased Cho/Cr and mI/Cr compared with controls. In the follow-up study, 36% of the MCI subjects [atypical MCI (atMCI)] showed interval increases in NAA, Cr, and Glx levels compared with 64% of MCI subjects (typical MCI) who showed an interval decrease in NAA, Cr, and Glx. Both MCI subgroups had higher Clinical Dementia Rating scores and lower scores on episodic memory, phonemic, and semantic word fluency tasks, compared with controls. The annualized rate of change in metabolic and cognitive status did not differ between normal aging and MCI subjects. atMCI subjects showed significant negative correlations between metabolite levels and executive function task scores, with NAA/mI showing a significant positive correlation with phonemic and semantic word fluency. There were no significant correlations between metabolite levels and cognitive performance in tMCI subjects; however, NAA/mI and mI/Cr were negatively correlated with executive function tasks. These results indicate 2 distinct evolving metabolite profiles that correlate with changes in executive function and can be used to differentiate MCI from normal aging.     

壳聚糖、磷脂酰胆碱对轻度认知功能障碍患者脑组织氢质子磁共振波谱成像的影响

目的观察壳聚糖、磷脂酰胆碱对轻度认知功能障碍(MCI)患者海马氢质子磁共振波谱成像(1H-MRSI)的影响。方法对15例MCI患者(MCI组)和15名正常老年人(正常对照组)进行海马1H-MRSI检查。给予MCI组患者壳聚糖、磷脂酰胆碱治疗2个月后对其进行复查,比较N-乙酰天门冬氨酸(NAA)/肌酸(Cr)、胆碱(Cho)/Cr、肌醇(mI)/Cr的比值。结果与正常对照组相比,MCI组服药前、后NAA/Cr比值显著降低,mI/Cr比值显著升高(均P<0.05),Cho/Cr的差异无统计学意义。MCI组治疗后的NAA/Cr比值较治疗前明显升高(P<0.05),mI/Cr比值明显降低(P<0.05),Cho/Cr比值治疗前后的差异无统计学意义。结论1H-MRSI显示,壳聚糖和磷脂酰胆碱能改善脑组织的代谢,可能对MCI有一定的治疗作用。     

Proton magnetic resonance spectroscopy (H-MRS) of the thalamus in schizophrenia

This study applied ¹H-MRS in the thalamus of schizophrenic patients and healthy subjects.There were no differences in the metabolite ratios (NAA/Cr, Cho/Cr or mI/Cr) between the two groups. Relationships were noted between NAA/Cr and age in patients with a trend toward this correlation in controls, suggesting an effect of age on the metabolism of the thalamus.     

MRI和磁共振波谱在肝性脑病的应用价值

目的探讨MRI和磁共振波谱(1H-MRS)在肝性脑病中的应用价值。方法对6例肝性脑病患者行MRI和1H-MRS检查,检测基底节MRS的N-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱(Cho)、谷氨酰胺复合物(Glx)、肌醇(mI)的峰值,计算Cho、mI、NAA与Cr的比值,并与5名正常对照者比较。结果 MRI检查显示,6例肝性脑病患者双侧基底节T1WI均出现高信号,其中1例累及内囊、2例累及尾状核、1例累及中脑被盖;5例患者T2WI未见明显异常信号,1例患者因并发弥漫性脑水肿T2WI出现广泛高信号影。1H-MRS显示,肝性脑病组双侧基底节Cho峰、mI峰、Cho/Cr和mI/Cr显著低于正常对照组,Glx峰显著高于正常对照组(P<0.01～0.005);两组NAA/Cr比较差异无统计学意义。结论 MRI显示双侧基底节T1WI高信号是肝性脑病特征性改变。1H-MRS能准确地反映其脑代谢物质水平的变化。     

Assessment of metabolic changes within normal appearing gray and white matter in children with growth hormone deficiency: Magnetic resonance spectroscopy and hormonal correlation

Objective: The pathogenesis of idiopathic growth hormone deficiency (GHD) in children, including possible cerebral metabolic alterations, remains unclear. The aim of the study was to evaluate metabolic changes within the normal appearing brain in children with GHD using MR spectroscopy (MRS) and to correlate MRS measurements with hormonal concentrations and with pituitary gland size. Methods: Seventy children with GHD (mean age 7.8 yrs) and 11 healthy controls (mean age 8.4 yrs) were enrolled in the study. The MRS examinations were performed on a 1.5T scanner. Voxels were located in the posterior cingulate gyrus (PCG) and the left parietal white matter (PWM). The NAA/Cr, Cho/Cr and mI/Cr ratios were analyzed. The metabolite ratios, pituitary gland size and hormonal concentrations: growth hormone (GH) in two stimulation tests and GH during the night, as well as IGF-1 (insulin-like growth factor) and IGFBP3 (insulin-like growth factor-binding protein) levels were also correlated. Results: There was a significant (p < 0.05) decrease of the NAA/Cr ratios in PCG and PWM in children with GHD compared to the normal subjects. Other metabolite ratios showed no significant differences. We also found significant positive correlations between NAA/Cr ratio in PWM and IGFBP3 level, as well as with GH concentration in a stimulation test with glucagon. Conclusions: The reduction of NAA/Cr ratios may suggest loss of neuronal activity within normal appearing gray and white matters in children with GHD. MRS could be a sensitive marker of cerebral metabolic disturbances associated with GHD and maybe used as an additional indicator for therapy with recombinant GH.     

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 ((1)H-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 (1)H-MRS studies has been unable to evaluate global or lateralized abnormalities in neuronal or membrane function. Using automated multivoxel two-dimensional CSI (1)H-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 (1)H-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.     

磁共振波谱分析对轻微型肝性脑病患者的诊断价值

目的研究磁共振波谱分析(MRS)对轻微型肝性脑病(MHE)患者的诊断价值。方法应用3.0MR机对26例MHE患者进行扣带回和额叶的单体素点分辨自旋回波波谱序列扫描。计算N-乙酰天门冬氨酸(NAA)、肌酐(Cr)、胆碱(Cho)、肌醇(mI)和谷氨酰胺复合物(Glx)的峰下面积,计算NAA/Cr、Cho/Cr、mI/Cr、Glx/Cr的值,并与正常对照组比较。结果与正常对照组相比,MHE组扣带回和额叶的Cho/Cr、mI/Cr显著降低(P<0.01～0.001),Glx/Cr值显著升高(均P<0.005),NAA/Cr值差异无统计学意义(均P>0.05)。结论MHE患者MRS检查显示扣带回和额叶Cho、mI水平降低,Glx水平升高,MRS对MHE的诊断有显著价值。     

Single voxel magnetic resonance spectroscopy at 3 Tesla in a memory disorders clinic: early right hippocampal NAA/Cr loss in mildly impaired subjects

In this study, we use magnetic resonance spectroscopy (MRS) at 3 Tesla to measure N-acetyl aspartate (NAA), myo-inositol (mI) and choline (Cho) to creatine (Cr) ratios in R (right) and L (left) hippocampi (H) in 8 mildly memory impaired (MMI), 6 probable Alzheimer's Disease (PRAD), and 17 control subjects. NAA/Cr was significantly reduced in the RH in the MMI group and bilaterally in the PRAD group vs. controls. No other metabolite differences were noted between the three groups. Five MMI subjects have converted to PRAD in follow-up. These findings suggest that RH NAA/Cr ratios measured at 3 Tesla may be a sensitive marker of future progression to dementia in a clinically defined population with isolated memory complaints.