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.     

正常人丘脑质子磁共振波谱分析

背景：磁共振波谱使神经影像学从单纯形态学观察进入到分子水平上的探索,有研究利用磁共振波谱发现疾病发生时丘脑生化代谢物质与正常人存在差异。 目的：利用氢质子磁共振波谱(1H-MRS)观察正常人的丘脑代谢特点,为正常人及脑部疾患的相关治疗提供客观依据。 设计、时间及地点：自身对照,横断面调查,于2007-08/2008-08在解放军第九一中心医院影像中心完成。 对象：选择解放军第九一中心医院附近社区的精神正常的居民及学生共56名,男32名,女24名。所有受检者或其监护人均对调查方案知情同意,并签署知情同意书, 方法：采用1.5T超导型磁共振成像系统,入组24 h后采用多体素1H-MRS检测丘脑生化代谢物N-乙酰天冬氨酸、胆碱复合物与肌酸复合物。 主要观察指标：用随机软件测量N-乙酰天冬氨酸、胆碱复合物、肌酸复合物的峰下面积,以肌酸复合物峰为参照,计算机自动完成N-乙酰天冬氨酸/肌酸复合物值、胆碱复合物/肌酸复合物值、N-乙酰天冬氨酸/(胆碱复合物+肌酸复合物)值的计算。 结果：正常人丘脑1H-MRS左侧N-乙酰天冬氨酸/肌酸复合物、N-乙酰天冬氨酸/(胆碱复合物+肌酸复合物)高于右侧,胆碱复合物/肌酸复合物低于右侧,但差异但差异无显著性意义(P > 0.05)。经Pearson分析,丘脑双侧各观察指标与年龄均无相关性(P > 0.05);不同性别间比较,男性组左右两侧N-乙酰天冬氨酸/肌酸复合物、右侧胆碱复合物/肌酸复合物、左侧N-乙酰天冬氨酸/(胆碱复合物+肌酸复合物)均高于女性组,余观察指标低于女性组,但差异均无显著性意义(P > 0.05)。 结论：正常人丘脑代谢物双侧无差异,代谢物水平可能并不受性别和年龄的影响。     

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.     

Proton magnetic resonance spectroscopy of the anterior cingulate gyrus, insular cortex and thalamus in schizophrenia associated with idiopathic unconjugated hyperbilirubinemia (Gilbert's syndrome)

OBJECTIVE: To examine whether patients with schizophrenia associated with idiopathic unconjugated hyperbilirubinemia (Gilbert's syndrome [GS]) have specific changes in brain metabolism. METHODS: We applied proton magnetic resonance spectroscopy (H-MRS) to the anterior cingulate gyrus, insular cortex and thalamus of patients with schizophrenia and GS (n = 15) or without GS (n = 15), all diagnosed with schizophrenia according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV), and healthy subjects (n = 20). RESULTS: In the anterior cingulate gyrus, patients with schizophrenia and GS showed significant decreases in N-acetyl aspartate/creatine-phosphocreatinine (NAA/Cr), choline/creatine-phosphocreatinine (Cho/Cr) and myoinositol/creatine-phosphocreatinine (ml/Cr) ratios compared with healthy subjects and compared with patients with schizophrenia without GS. Patients with schizophrenia without GS also showed significant decreases in NAA/Cr, Cho/Cr and ml/Cr compared with healthy subjects. In the insular cortex, patients with schizophrenia and GS showed significant decreases in NAA/Cr, Cho/Cr and ml/Cr compared with healthy subjects and compared with patients with schizophrenia without GS. Patients with schizophrenia without GS also showed significant decreases in NAA/Cr, Cho/Cr and ml/Cr compared with healthy subjects. In the thalamus, patients with schizophrenia and GS showed significant decreases in NAA/Cr, Cho/Cr and ml/Cr compared with healthy subjects, whereas patients with schizophrenia without GS only showed a significant decrease in ml/Cr compared with healthy subjects. CONCLUSIONS: Our findings suggest that brain metabolism is more severely compromised in the subtype of schizophrenia with GS.     

精神分裂症患者前额叶和丘脑的质子磁共振波谱研究

Objective To identify the metabolite levels in prefrontal lobe and thalamus in patients with schizophrenia by proton magnetic resonance spectroscopy (1H-MRS). Methods Thirty-eighty schizophrenics and 38 normal controls were involved in this study. A multi-voxel 1H-MRS was given to all the subjects on prefrontal lobe and thalamus within 24 hours they got in hospital. The N-acetylaspartate (NAA), choline-congtaining compounds (Cho), and creatine compounds (Cr) were measured and the ratios of NAA/Cr, Cho/Cr and NAA/( Cho + Cr) were determined Results In left prefrontal lobe and bilateral thalamus, the NAA/Cr ratio in patients demonstrated lower than that in normal controls ( all P <0. 05). In left prefrontal lobe, the NAA/(Cho + Cr) ratio in patients showed lower than that in normal controls (0. 64 ±0. 13 vs. 0. 74±0. 22,t =2. 26, P<0. 05). Both in patients and in normal controls, there were no significant differences in NAA/Cr, Cho/Cr and NAA/(Cho + Cr) between the two sides (all P >0. 05). Conclusious Abnormalities in neuronal function and/or integrity are present in schizophrenics.There is no significantly lateralized asymmetry for metabolite levels such as NAA, Cho and Cr in either the schizophrenics or the controls.     

初发抑郁症患者丘脑质子磁共振波谱分析

目的探讨未用药首发抑郁症患者丘脑的脑代谢有无异常。方法利用质子磁共振波谱分析技术(1H-MRS)检测20例未用药首发抑郁症患者和20名健康志愿者丘脑的多个代谢指标,包括乙酰天门冬氨酸盐(NAA)、谷氨酰胺和谷氨酸复合物(Glx)、胆碱复合物(Cho)、肌酸-磷酸肌酸复合物(Cr)等。结果与对照组相比,患者组双侧丘脑NAA/Cr下降,但只有右侧的差异有统计学意义(t=2.923,P<0.05);两组间各代谢值、Cho/Cr和Glx/Cr的差异无统计学意义(P>0.05);轻度抑郁组和重度抑郁组间比较,各代谢值的差异均无统计学意义(P>0.05)。结论初发抑郁症患者右侧丘脑可能存在神经元受损和线粒体代谢障碍。     

磁共振波谱检测肌萎缩侧索硬化的上运动神经元损害

目的探讨质子磁共振波谱(proton magnetic resonance spectroscopy,1 H-MRS)检测肌萎缩侧索硬化(amyotrophic lateral sclerosis,ALS)的上运动神经元损害(upper motor neuron,UMN)的特点和诊断准确性。方法收集ALS患者31例和健康对照32名,采用1 H-MRS检测脑中央前回皮质下、内囊后肢和大脑脚感兴趣区代谢产物N-乙酰天冬氨酸(NAA)、胆碱(Cho)、肌酸(Cr)的水平,计算NAA/Cr、NAA/(Cho+Cr)、Cho/Cr比值,采用受试者工作特征(receiver operating characteristic,ROC)曲线分析1 H-MRS对ALS患者UMN损害的诊断价值。结果 ALS患者各锥体束走行部位和部位组合的NAA/Cr和NAA/(Cho+Cr)较对照组显著降低(P0.05)。NAA比值预测ALS的UMN损害的ROC曲线下面积(area under the curve,AUC)为0.67~0.91,其中内囊后肢、大脑脚两部位的平均NAA/(Cho+Cr)和三部位的平均NAA/(Cho+Cr)的AUC、灵敏度、特异度分别为0.91、0.828、0.906和0.90、0.769、0.875。结论 1 H-MRS可检出ALS患者锥体束走行的生化代谢异常,是评估ALS的UMN损害的客观影像学指标,其诊断准确性中等,多水平检测和综合指标的选择有助于提高其诊断效力。     

Proton spectroscopy in medication-free pediatric attention-deficit/hyperactivity disorder.

BACKGROUND: The frontal-striatal pathway has been previously implicated in the neuropathology of attention-deficit/hyperactivity disorder (ADHD). Hence, we used proton magnetic resonance spectroscopy (1H-MRS) to examine metabolite levels in the prefrontal cortex of children with ADHD. METHODS: Nine age- and gender-matched case-control pairs were examined, ages 7 to 16 years. A long-echo 1H-MRS scan was acquired from the right prefrontal cortex and left striatum in all subjects. Compounds that can be visualized with 1H-MRS include N-acetyl-aspartate (NAA), glutamate/glutamine/gamma-aminobutyric acid (Glx), creatine/phosphocreatine (Cr), and choline compounds (Cho). RESULTS: Frontal-striatal glutamatergic resonances were elevated in the children with ADHD as compared to healthy control subjects. No differences were noted in NAA, Cho, or Cr metabolite ratios. CONCLUSIONS: These findings suggest that frontal-striatal Glx resonances may be increased in children with ADHD in comparison with healthy control subjects.     

Reduction in hypothalamic 1H-MRS metabolite ratios in patients with cluster headache

OBJECTIVE: To determine the 1H-MR spectroscopic (MRS) findings in the hypothalamus in patients with episodic cluster headache. METHODS: 47 patients were recruited with episodic cluster headache (35 in cluster period and 12 in remission), 21 normal controls, and 16 patients with chronic migraine. The hypothalamic 1H-MRS metabolite ratio changes in patients with cluster headache were evaluated and compared with results in the normal controls as well as patients with chronic migraine. Seven patients in the cluster period group underwent a follow up hypothalamic MRS study five to six months after remission. RESULTS: In patients with cluster headache, the hypothalamic N-acetylaspartate (NAA)/creatine (Cr) and choline (Cho)/Cr ratios were similar between those in cluster period and in remission. As a group, both NAA/Cr and Cho/Cr levels were significantly lower in patients with cluster headache in comparison with either the control or chronic migraine groups. In those with a follow up MRS study, the levels of metabolite ratios did not differ between the cluster and remission periods. CONCLUSIONS: This study provides evidence of persistent biochemical change of the hypothalamus in patients with episodic cluster headache. Low levels of NAA/Cr and Cho/Cr suggest that cluster headache might be related to both neuronal dysfunction and changes in the membrane lipids in the hypothalamus.     

正常人半卵圆中心质子磁共振波谱研究

目的运用质子磁共振波谱（^1H-MRS）研究年龄对正常人半卵圆中心脑组织代谢物浓度的影响。方法对80例健康成人双侧半卵圆中心进行^1H-MRS检测,对比分析不同年龄组的半卵圆中心N-乙酰基天门冬氨酸（NAA）/肌酸复合物（Cr）和含胆碱化合物（Cho）/Cr比值的变化。结果随着年龄的增长,在≤50岁年龄段半卵圆中心的NAA/Cr和Cho/Cr比值无明显改变,但在〉50岁年龄段半卵圆中心的NAA/Cr比值逐渐降低、Cho/Cr比值逐渐增高。结论^1H-MRS是可以为正常人半卵圆中心与年龄相关的代谢物浓度的改变提供有价值的信息的一种无创技术。     

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.     

Thalamic neurometabolic alterations in tremulous Parkinson's disease: A preliminary proton MR spectroscopy study

IntroductionThe objective of this study was to investigate the thalamic biochemical changes in tremor-dominant Parkinson's disease (tPD) patients in comparison with essential tremor with resting tremor (rET) patients, by using proton MR spectroscopy (¹H-MRS).MethodsFourteen tPD patients, 12 rET patients and 10 controls participated in this study. All patients underwent dopamine transporter single-photon emission computed tomography (DAT-SPECT) with ¹²³I-ioflupane, and a short-echo single-voxel ¹H-MRS on a 3T scanner. A voxel of 10 × 15 × 10 mm involving the Vim nucleus was acquired in both thalami of all subjects. Peak areas of N-acetyl-aspartate (NAA), creatine (Cr), glycerophosphocholine (Cho), and glutamate (Glu) were measured for each voxel using LCModel. The NAA/Cr, Cho/Cr, and Glu/Cr ratios were then calculated.ResultsDAT-SPECT was abnormal in tPD patients, whereas it was normal in rET patients. Patients with tPD showed a significant reduction of NAA/Cr and Cho/Cr in the thalami compared to rET and healthy controls; whereas there were no significant differences between rET patients and controls. The combination of thalamic NAA/Cr and Cho/Cr ratios showed a 100% accuracy in distinguishing tPD patients from rET patients and controls.ConclusionsThis study provides preliminary evidence that thalamic neurometabolic abnormalities occur in tremor-dominant phenotype of PD, and suggests that ¹H-MRS can help differentiate patients with tPD from those with rET.     

Neurochemical pathology in hippocampus in euthymic patients with bipolar I disorder

Objective: Subcortical regions such as hippocampus, thalamus and ventral putamen are assumed to be involved in the pathophysiology of mood regulation. Disturbed hippocampal neuronal function indicated by reduced N‐acetyl‐aspartate (NAA) levels in bipolar patients was shown by several studies. Results in thalamus and putamen are inconsistent. Method: N‐acetyl‐aspartate, choline (Cho), creatine (Cr) and myo‐inositol (Ins) were measured in left hippocampus, left thalamus and left putamen using proton magnetic resonance spectroscopy in 13 euthymic patients with bipolar I disorder and 13 pairwise matched healthy control subjects. Metabolic ratios NAA/Cr, NAA/Cho, Cho/Cr and Ins/Cr were calculated. Results: Patients with bipolar I disorder demonstrated significantly reduced NAA/Cr in the left hippocampus compared with healthy control subjects. No alterations were found in thalamus or putamen. Conclusion: We hypothesize that this NAA/Cr reduction might reflect neuronal dysfunction in the left hippocampus in patients with bipolar disorder.     

Neurochemical correlates of cognitive dysfunction in patients with leukoaraiosis: a proton magnetic resonance spectroscopy study

Abstract

Objectives: Leukoaraiosis (LA) is a common radiological finding in the elderly and may reflect cerebral small vessel disease (SVD). Although SVD has been identified as a major cause of vascular cognitive impairment or vascular dementia, the mechanisms for this association remain unclear. We therefore aimed to measure brain metabolites in LA using proton magnetic resonance spectroscopy (¹H-MRS) as to determine the relationship between cognitive function and neurochemical white matter profile.

Methods: We recruited 23 patients with LA and 23 age- and sex-matched healthy controls consecutively. Multi-voxel ¹H-MRS was performed with a volume of interest located in centrum semiovale that contained mainly white matter voxels. Three main ratios of N-acetyl aspartate (NAA)/Cr, choline (Cho)/Cr and NAA/Cho were obtained. Spearman rank correlation coefficients were calculated between the cognitive function and the measured metabolite ratios.

Results: We found significantly lower levels of NAA/Cho and NAA/Cr ratios in lesioned white matter in patients with LA than healthy controls (P<0·05). The ratios of NAA/Cho and NAA/Cr in normal appearing white matter (NAWM) were higher than lesioned white matter and lower than controls, but this difference was not significant (P>0·05). There was a positive relationship between Mini-Mental State Examination (MMSE) and NAA/Cho in NAWM (r?=?0·417, P?=?0·048), and also a positive relationship between MMSE and NAA/Cr in lesioned white matter (r?=?0·551, P?=?0·006) in patients with LA. A positive relationship between the Z scores of the executive function and NAA/Cho in lesioned white matter (r?=?0·557, P?=?0·006) was also found.

Conclusion: The main finding of this study was a significant reduction in the ratios of NAA/Cr and NAA/Cho in lesioned white matter, which indicates a marker of neuronal loss or dysfunction in patients with LA, which was correlated with cognitive function. This relationship between cognitive function and metabolic changes suggests that ¹H-MRS can be explored as a marker for cognitive dysfunction in patients with LA.     

Application of proton magnetic resonance spectroscopy on substantia nigra metabolites in Parkinson’s disease

This study investigates changes in substantia nigra metabolites in Parkinson’s disease (PD) using proton magnetic resonance spectroscopy (¹H- MRS). Thirty patients with asymmetric PD and 20 normal controls were included in this study. Substantia nigra metabolites were detected in all subjects using 3D-multimer ¹H-MRS with a 3.0 T MRI scanner. The relative ratios of NAA/Cr, NAA/Cho, NAA/(Cho + Cr) in the substantia nigra were compared between two sides of asymmetric PD patients as well as between PD patients and controls. Significant differences in NAA/Cr, NAA/Cho, NAA/(Cho + Cr) were observed between PD patients and healthy controls (P?<?0.05) as well as between the ipsilateral and contralateral of affected extremity in PD patients (P?<?0.05). Significant differences in NAA/Cr, NAA/Cho, NAA/(Cho + Cr) were also observed between patients with mild and severe PD. Thus, we found that ¹H-MRS can be used to detect substantia nigra metabolites in PD patients, which may be useful for early diagnosis and evaluation of PD.     

Thalamic abnormalities in patients with schizophrenia revealed by proton magnetic resonance spectroscopy

Recent investigations suggest that thalamic abnormalities may underlie symptom formation in schizophrenia. We previously demonstrated reduced concentrations of N-acetylaspartate (NAA) in tissue from the thalamus of schizophrenic patients using in vitro proton magnetic resonance spectroscopy (1H-MRS). In the present study, in vivo 1H-MR spectra of the left thalamus and frontal lobe were investigated in 20 patients with schizophrenia and 16 age-matched control subjects to replicate our previous postmortem findings and support the hypothesis of thalamic abnormality in schizophrenia. Schizophrenic patients showed significantly lower NAA/total creatine (Cr) and choline-containing compounds (Cho)/Cr ratios in the thalamus than control subjects, while no significant difference was found in the frontal lobe. There was no significant correlation in the schizophrenic patients between the NAA/Cr or Cho/Cr ratio and other clinical data including clinical symptoms or neuroleptic dosage. These findings may further support other studies suggesting decreased thalamic volume or neuronal number and/or thalamic dysfunction, and reduction in size of white matter tracts adjacent to the thalamus in schizophrenia, as well as our previous postmortem MRS study.     

Proton magnetic resonance spectroscopy of the motor cortex in 70 patients with amyotrophic lateral sclerosis

OBJECTIVE: To evaluate proton magnetic resonance spectroscopy for detection and monitoring of upper motoneuron degeneration in patients with amyotrophic lateral sclerosis. METHODS: Seventy patients with amyotrophic lateral sclerosis according to the El Escorial criteria were compared with 48 healthy control subjects. Single-volume proton magnetic resonance spectroscopy (echo time, 272 milliseconds; repetition time, 2000 milliseconds) was performed in both motor cortices for detection of N-acetylaspartate (NAA), phosphocreatine + creatine ([P]Cr), and choline-containing compounds (Cho) to calculate the metabolite ratios NAA/Cho, NAA/(P)Cr, and Cho/(P)Cr. In addition, absolute metabolite concentrations of NAA, (P)Cr, and Cho were obtained in 30 patients and 15 controls with the unsuppressed water signal used as an internal reference. RESULTS: Absolute concentrations of NAA (P<.001) and (P)Cr (P<.05) were reduced in motor cortices of patients, whereas Cho concentrations remained unchanged. The NAA/Cho and NAA/(P)Cr ratios were reduced in all El Escorial subgroups (P<.001). The Cho/(P)Cr ratio was elevated in patients with definite amyotrophic lateral sclerosis (P<.05). Metabolite ratio changes corresponded to the lateralization of clinical symptoms and were weakly correlated with disease duration and disease severity. In follow-up observations of 16 patients during a mean (+/-SD) of 12.1 +/- 8.7 months, NAA/Cho dropped by 9.1% (P<.01), and Cho/(P)Cr increased by 7.0% (P<.01). Changes of metabolite ratios were significantly correlated with progression of disease severity. CONCLUSIONS: Measurement of NAA concentrations and NAA/Cho ratios appear to be most suitable for detection of motor cortex degeneration by single-volume proton magnetic resonance spectroscopy. Reduced NAA/Cho ratios correspond to aspects of the clinical presentation and reflect disease progression in follow-up measurements.     

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.     

Thalamic involvement in neurofibromatosis type 1: evaluation with proton magnetic resonance spectroscopic imaging

Neurofibromatosis type 1 is a common autosomal dominant disorder associated with learning disabilities. In addition to gliomas and other tumors, T2 hyperintense lesions (unidentified bright objects or UBOs) are frequently found in the globus pallidus, cerebellum, and white matter regions. To better characterize supratentorial UBO functional significance, we studied by quantitative magnetic resonance spectroscopic imaging (MRSI) 9 male subjects with neurofibromatosis type 1 (age, 6-19 years) and 9 age-matched and sex-matched controls. Maps of the anatomical distribution of the metabolites choline (Cho), N-acetylaspartate (NAA), and creatine were calculated in four axial 15-mm slices. Absolute metabolite concentrations within UBOs, unaffected globus pallidus, and thalami demonstrated an age-related pattern, characterized by elevated Cho and relatively preserved NAA in younger subjects (<10 years) and reduced NAA and normal Cho in older subjects. These changes were found in both UBOs and thalami but were only significant for NAA, NAA/creatine, and NAA/Cho in the latter region. Decreases in NAA ratios were most severe in the thalami of subjects with UBOs in the globus pallidus, whereas UBOs showed similar but milder abnormalities than those in the thalamus. We speculate that the MRSI metabolic abnormality may represent a more generalized phenomenon, without a T2 signal counterpart in the affected brain regions. Based on the neuropathological study by DiPaolo and colleagues (1995), we postulate that Cho elevations reflect increased myelin turnover in areas of intramyelinic edema, which is followed by neuropil injury (reduced NAA). Temporal progression and behavioral correlates of these MRSI changes deserve further exploration.     

阳性症状为主型精神分裂症首次发病患者前额叶和海马磁共振质子波谱成像研究

目的 探讨阳性症状为主型精神分裂症首次发病患者前额叶和海马的磁共振质子波谱(1H-MRS)变化特点,为其病因学探讨提供线索.方法 对22例首次发病精神分裂症阳性症状为主型患者(患者组)和11名年龄、性别、受教育时间均匹配的正常对照者(对照组),应用2D 1H-MRS成像技术检测2组双侧前额叶白质、前扣带回皮质、海马N-乙酰天门冬氨酸(NAA)、胆碱(Cho)、肌酸(Cr)3种代谢物,分别计算NAA/Cr和Cho/Cr的比值;采用配对t检验、独立样本t检验进行统计分析.结果 (1)患者组左侧额叶白质NAA/Cr和Cho/Cr分别为(1.63±0.30)和(1.23±0.26),均低于对照组[(2.10±0.30)、(1.54±0.25)],右侧额叶白质NAA/Cr(1.70±0.34)低于对照组(1.97±0.34),差异有统计学意义(P<0.01和P<0.05);(2)双侧前扣带回皮质NAA/Cr、Cho/Cr值与对照组差异无统计学意义(P>0.05);(3)患者组右侧海马NAA/Cr(1.59±0.27)高于对照组(1.24±0.17),差异有统计学意义(P<0.01);(4)对照组内左侧额叶白质Cho/Cr(1.54±0.25)高于右侧(1.35±0.18),左侧海马NAA/Cr(1.45±0.28)高于右侧(1.24±0.17),差异均有统计学意义(P<0.05);(5)患者组内左侧海马NAA/Cr和Cho/Cr分别为(1.43±0.27)和(1.39±0.38),均低于右侧[(1.59±0.27)、(1.56±0.39)],差异有统计学意义(P<0.05).结论 首发精神分裂症阳性症状为主型患者的1H-MRS代谢物与正常人存在差异,提示阳性症状为主型患者存在双侧前额叶白质、海马的神经功能障碍.

Abstract：

Objective To identify the possible alteration of brain functioning in prefrontal lobes and hippocampus in the first-episode positive symptoms of schizophrenia using proton magnetic resonance spectroscopy (1H-MRS). Methods 1H-MRS was performed on prefrontal white matter, anterior cingulated cortex and hippocampus in 22 patients and 11 age-, sex-, and education-matched right-handed healthy controls. The ratios of N-acetylaspartate (NAA)/creatine (Cr) and choline-containing compounds (Cho)/Cr were calculated. Results The NAA/Cr and Cho/Cr ratios in the left prefrontal white matter in patients were lower than that in normal controls (patients, NAA/Cr 1. 63 ±0. 30; Cho/Cr 1. 23 ±0. 26; controls, NAA/Cr 2. 10 ±0. 30; Cho/Cr 1. 54 ± 0. 25, P<0. 01) , and NAA/Cr in the right prefrontal white matter was lower in patients than in controls (patients 1. 70 ± 0. 34; controls 1. 97 ± 0. 34, P<0. 05). There were no significant difference in NAA/Cr, Cho/Cr for the bilateral anterior cingulated cortex between patients and controls (P>0. 05). The ratio of NAA/Cr in the right hippocampus was significantly higher in patients than that in controls (patients 1. 59 ± 0. 27; controls 1. 24 ± 0. 17, P<0. 01). In addition, in healthy controls,Cho/Cr was significantly higher in the left prefrontal white matter than in the right (left 1. 54 ± 0. 25; right 1. 35 ±0. 18, P<0. 05) , and NAA/Cr in the left hippocampus was significantly higher than in the right (left 1. 45 ± 0. 28; right 1. 24 ± 0. 17, P<0. 05). While NAA/Cr and Cho/Cr in the left hippocampus were significantly lower than in the right hippocampus in schizophrenia patients (left, NAA/Cr 1.43 ± 0. 27;Cho/Cr 1.39 ±0.38; right, NAA/Cr 1.59 ±0.27; Cho/Cr 1.56 ±0.39, P<0.05). Conclusion There is the significant difference of manifestation of 1H-MRS between schizophrenia patients with positive symptoms and normal controls, which reflects neuronal dysfunction in the prefrontal lobes and hippocampus.