1H MRS of basal ganglia and thalamus in amyotrophic lateral sclerosis

Previous studies have evaluated motor and extramotor cerebral cortical regions in patients with amyotrophic lateral sclerosis (ALS) using (1) H MRS, but none have evaluated the thalamus or basal ganglia. The objective of this exploratory study was to evaluate the subclinical involvement of the basal ganglia and thalamus in patients with ALS using (1) H MRS. Fourteen patients (52±7 years) with sporadic definite ALS and 17 age-matched controls were studied using volumetric MRSI on a 3-T scanner. The concentration of the metabolites N-acetylaspartate (NAA), choline (Cho) and their ratio (NAA/Cho) were obtained bilaterally from the basal ganglia (lentiform nucleus, caudate) and thalamus. The maximum rates of finger and foot tap and lip and tongue movements were obtained to assess extrapyramidal and pyramidal tract function. In patients with ALS, relative to controls, the NAA concentration was significantly lower (p<0.02) in the basal ganglia and thalamus, and the Cho concentration was higher (p<0.01) in these structures, except in the caudate (p=0.04). Correspondingly, the NAA/Cho ratio was significantly lower (p<0.01) in these structures, except in the caudate (p=0.03), in patients than in controls. There were mild to strong correlations (r=0.4-0.7) between the metabolites of the basal ganglia and finger tap, foot tap and lip and tongue movement rates. In conclusion, decreased NAA in the basal ganglia and thalamus and increased Cho and decreased NAA/Cho in the lentiform nucleus and thalamus are indicative of neuronal loss or dysfunction and alterations in choline-containing membranes in these structures.     

皮质下缺血性脑血管病的磁共振波谱研究

目的:检测皮质下缺血性脑血管病(SIVD)患者和正常对照组不同脑区脑组织的代谢水平,探讨其与认知功能损害的关系。方法:采用多体素磁共振波谱(1 H-MRS)技术评测SIVD患者(SIVD组,n=32例)和体检健康人(对照组,n=21)额叶及顶叶皮质、白质的代谢物N-乙酰天门冬氨酸(NAA)、胆碱(Cho)、肌酸(Cr);计算有关比值NAA/Cr、Cho/Cr,分析有无认知功能损害SIVD患者上述比值的变化。结果:(1)SIVD组额叶皮质、白质及顶叶皮质、白质各体素NAA/Cr比值明显低于对照组(P0.01);(2)SIVD组顶叶皮质及白质的Cho/Cr比值明显高于对照组(P0.01);(3)SIVD组有认知功能损害患者的额叶皮质和顶叶皮质、白质NAA/Cr比值显著低于无认知功能损害者(P值分别0.01、0.01、0.05),Cho/Cr比值的两者间差异无统计学意义(P0.05)。结论:SIVD患者脑组织存在NAA/Cr、Cho/Cr比值改变,且额叶皮质和顶叶皮质、白质NAA/Cr的下降与认知损害有关。     

Metabolite alterations in autistic children: a 1H MR spectroscopy study

PurposeThe purpose of this study was to assess the role of proton magnetic resonance spectroscopy (1H MRS) in the detection of changes in cerebral metabolite levels in autistic children.Material and methodsStudy group consisted of 12 children, aged 8–15 years, who were under the care of Pediatric Neurology Department and Pediatric Rehabilitation Department of Medical University of Bialystok. The diagnosis of autism was established by neurologist, psychiatrist and psychologist in every case. All patients matched the clinical criteria of the disease according to International Statistical Classification of Diseases and Related Health Problems (ICD-10). The control group included 16 healthy children aged 7–17. ¹H MRS was performed with a single-voxel method (TE-36, TR-1500, NEX-192). The volume of interest (VOI) was located in the frontal lobe regions, separately on each side.ResultsWe showed lower N-acetylaspartate/creatine (NAA/Cr), γ-aminobutyric acid /creatine (GABA/Cr) and glutamate/creatine (Glx/Cr) in the frontal lobes in the study group comparing with healthy controls. The ratio of myoinositol/creatine (mI/Cr) was increased in autistic children. No differences in choline/creatine (Cho/Cr) ratio in study group and controls were found. There was a correlation between age and NAA/Cr in autistic children (R=0.593 p=0.041). No significant differences in metabolite ratios between right and left hemisphere in ASD and controls were found.Conclusions¹H MRS can provide important information regarding abnormal brain metabolism. Differences in NAA/Cr, GABA/Cr, Glx/Cr and mI/Cr may contribute to the pathogenesis of autism.     

Proton magnetic resonance spectroscopy in children with spastic diplegia

The objective of this prospective study was the application of proton magnetic resonance spectroscopy in children with spastic diplegia (SD) to determine the metabolite profile of SD children in the left basal ganglia, and to assess the relationship of this profile with motor and mental development. Patients with SD showed reduced ratios of N-acetylaspartate (NAA)/creatine (Cr), NAA/choline (Cho), NAA/myo-inositol (mI), Cho/NAA, Cho/Cr and Cho/mI in the basal ganglia compared to a well-matched control group. On the other hand, we noted increased Cr/NAA, Cr/Cho and mI/NAA ratios in the SD patients as compared with controls. NAA/mI ratios were positively correlated with the severity scale of cerebral palsy in SD children. There was also a significant correlation between Cr/NAA and mental retardation. Increased Cr/NAA, Cr/Cho and mI/NAA ratios in SD children may suggest the existence of the compensatory mechanisms in these patients. The NAA/mI ratio could be used as an additional marker of SD severity and Cr/NAA as a marker of the mental retardation.     

首发精神分裂症患者脑磁共振质子波谱的对照研究

目的研究首发精神分裂症患者脑磁共振质子波谱(1HMRS)的变化。方法对26例首发精神分裂症患者和12例正常人分别进行MRI常规扫描和1HMRS检查,1HMRS采用定点分辨率波谱序列(TR2000毫秒,TE135毫秒),所测定的代谢产物包括N-乙酰基天门冬氨酸(NAA)、肌酸复合物(Cr)、胆碱复合物(Cho)、肌醇(MI)、乳酸(Lac)、谷氨酸及谷氨酰胺(Glu-Gln)。结果精神分裂症患者前额叶背外侧回中NAA/Cr值和NAA/Cho值显著低于对照组前额叶背外侧回(1.83±0.15/2.42±0.13,t=3.202,P<0.01,2.37±0.16/2.06±0.24,t=2.453,P<0.05);患者组海马区中NAA/Cr值(1.65±0.19)和NAA/Cho值(1.12±0.21)显著低于对照组海马中的NAA/Cr值(1.83±0.27,t=2.532,P<0.05)和NAA/Cho值(1.34±0.12,t=2.641,P<0.05);且NAA/Cr的水平与简明精神障碍评定量表阴性症状总分呈负相关(r=-0.416,P<0.05);而丘脑、颞叶颞横回、枕叶脑区的NAA/Cr和NAA/Cho两组无显著性差异(P>0.05)。结论精神分裂症患者的1HMRS与正常人存在显著差异,提示精神分裂症存在神经元功能的异常,其前额叶背外侧回和海马两处脑区功能低下。     

颞叶癫癎磁共振波谱研究

目的 :探讨磁共振波谱 (magneticresonancespectrum ,MRS)检查对颞叶癫患者致灶的定位价值。方法 :对 36例颞叶癫患者进行MRS检查 ,主要分析波谱的三个峰 :N—乙酰天门冬氨酸 (NAA)峰位于 2 0 ppm ,总肌酸 (Cr)峰位于 3 0 ppm ,胆碱类物质 (Cho)峰位于 3 2ppm) ,根据波峰曲线下的绝对面积计算出NAA/ (Cr Cho)的比值 ,以NAA(Cr Cho) <0 6 8作为判断异常的标准。结果 :36例病人中 34例NAA/ (Cr Cho)比值 <0 6 8,其中双侧异常 2 1例 ,单侧异常 13例。结论 :MRS能准确反映体内NAA、Cho、Cr等代谢产物的变化 ,对颞叶癫的致灶有定位价值。     

Aerobic Fitness and the Brain: Increased N-Acetyl-Aspartate and Choline Concentrations in Endurance-Trained Middle-Aged Adults

Engagement in regular aerobic exercise is associated with cognitive benefits, but information on the mechanisms governing these changes in humans is limited. The goal of the current study was to compare neurometabolite concentrations relating to cellular metabolism, structure, and viability in endurance-trained and sedentary middle-aged adults. Twenty-eight endurance-trained and 27 sedentary adults, aged 40–65 years, underwent general health assessment, cardiorespiratory fitness measurement, neuropsychological testing, and proton magnetic resonance spectroscopy (¹H MRS). ¹H MRS was used to examine N-acetyl-aspartate (NAA), creatine (Cr), myo-inositol (mI), choline (Cho), and glutamate (Glu) concentrations in frontal and occipitoparietal grey matter. Group differences in concentrations of NAA, Cho, mI, and Glu, calculated as ratios over Cr, were explored using ANOVA. There were no significant differences in global cognitive function, memory, and executive function performance between the groups. In comparison to sedentary adults, the endurance-trained group displayed significantly higher NAA/Cr in the frontal grey matter (F(1, 53) = 5.367, p = 0.024) and higher Cho/Cr in the occipitoparietal grey matter (F(1, 53) = 5.138, p = 0.028). Within our middle-aged sample, endurance-trained adults demonstrated higher levels of NAA/Cr in the frontal grey matter and higher Cho/Cr in the occipitoparietal grey matter. Higher levels of NAA may indicate greater neuronal integrity and higher cerebral metabolic efficiency in association with cardiorespiratory fitness, whereas increased Cho may represent increased phospholipid levels secondary to neural plasticity.     

Identifying the translational complexity of magnetic resonance spectroscopy in neonates and infants

Little attention has been paid to relating MRS outputs of vendor‐supplied platforms to those from research software. This comparison is crucial to advance MRS as a clinical prognostic tool for disease or injury, recovery, and outcome. The work presented here investigates the agreement between metabolic ratios reported from vendor‐provided and LCModel fitting algorithms using MRS data obtained on Siemens 3 T TIM Trio and 3 T Skyra MRI scanners in a total of 55 premature infants and term neonates with hypoxic ischemic encephalopathy (HIE). We compared peak area ratios in single voxels placed in basal ganglia (BG) and frontal white matter (WM) using standard PRESS (TE = 30 ms and 270 ms) and STEAM (TE = 20 ms) MRS sequences at multiple times after birth from 5 to 60 days. A total of 74 scans met quality standards for inclusion, reflecting a spectrum of neonatal disease and several months of early infant development. For the long TE PRESS sequence, N‐acetylaspartate (NAA) and Choline (Cho) ratios to Creatine (Cr) correlated strongly between LCModel and vendor‐supplied software in the BG. For shorter TEs, the ratios of NAA/Cr and Cho/Cr were more closely related using STEAM at TE = 20 ms in BG and WM, which was significantly better than using PRESS at TE = 30 ms in the BG of HIE infants. At short TEs, however, it is still unclear which MRS sequence, STEAM or PRESS, is superior and thus more work is required in this regard for translating research‐generated MRS ratios to clinical diagnosis and prognostication, and unlocking the potential of MRS for in vivo metabolomics. MRS at both long and short TEs is desirable for standard metabolites such as NAA, Cho and Cr, along with important lower concentration metabolites such as myo‐inositol and glutathione.     

The clinical application of hydrogen magnetic resonance spectroscopy combining with diffusion weight imaging in brain gliomas grading

The present study was aimed to investigate the function of diffusion weight imaging (DWI) combining with magnetic resonance spectroscopy (MRS) in the grading of brain gliomas. 12 cases low grade and 17 cases high grade of brain gliomas patients were examined with DWI and MRS, with all tumors confirmed by pathology in advance. The apparent diffusion coefficient (ADC) values, their corresponding metabolite ratios of Cho/Cr, Cho/NAA and tumor cellularities of tumor solid enhanced parts were measured. The ratios of Cho/Cr and Cho/NAA and their corresponding ADC values had significant differences between their high and low grade gliomas values, respectively. The ADC values demonstrated a negative correlation with Cho/Cr, Cho/NAA, and a significant negative correlated with Cho/Cr. And the ADC values demonstrated strong negative correlations with tumor cellularities. DWI combining with MRS could provide more valuable information in evaluating gliomas grading.     

Improved reproducibility of MRS regional brain thermometry by 'amplitude-weighted combination'

Brain temperature is important in stroke and trauma. In birth asphyxia, hypothermia improves outcome, but local brain temperature information is needed to optimise therapy. The proton MRS water chemical shift (δ(water) ) is temperature dependent, and the in vivo brain temperature has often been estimated by measuring δ(water) relative to the N-acetylaspartate (NAA) singlet methyl resonance. However, the NAA peak amplitude may be reduced if cerebrospinal fluid occupies part of the MRS voxel and because of the lower concentration in immaturity, pathology and neonatal white matter. These factors can increase random and systematic δ(NAA) errors and also, therefore, MRS brain temperature errors. The aim of this study was to improve MRS brain temperature reproducibility and resilience to pathological, developmental and regional peak amplitude variations by amplitude-weighted combination (AWC) of brain temperatures (T(Cho) , T(Cr) and T(NAA) ) determined using the prominent choline (Cho), total creatine (Cr) and NAA resonances separately as chemical shift references. δ(water) - δ(Cho) , δ(water) - δ(Cr) and δ(water) - δ(NAA) were calibrated against tympanic temperature in piglet brain at 7 T (2.5-cm-diameter surface coil over the parietal lobes; binomial water suppression spin-echo sequence; TE = 540 ms; TR = 5 s). Eight normal human infants underwent thalamic region (Thal) and five occipito-parietal (OP) cerebral MRS at 2.4 T [point-resolved spectroscopy (PRESS) localisation; cubic voxel, 8 mL; water suppression off; TE = 270 ms; TR = 2 s]. AWC with T(Cho) , T(Cr) and T(NAA) weighted by the squared Cho, Cr and NAA peak amplitudes provided the smallest intersubject standard deviations: Thal, 0.45°C; OP, 0.33°C (for T(NAA) values of 0.65°C and 1.12°C, respectively). AWC provided resilience against simulated pathological alterations in Cho, Cr and NAA peak amplitudes, with Thal and OP T(AWC) changing by less than 0.04°C. AWC improves both intersubject reproducibility of MRS temperature estimation and resilience against pathological, anatomical and developmental variation of Cho, Cr and NAA peak amplitudes.     

Brain metabolic alterations in Cushing's syndrome as monitored by proton magnetic resonance spectroscopy.

Proton magnetic resonance spectroscopy ((1)H MRS) was used to evaluate changes in cerebral metabolites in 13 patients with Cushing's syndrome (including seven with pituitary corticotroph adenomas and six with primary adrenal disease) as compared to 40 normal subjects. Data were recorded in the frontal, thalamic and temporal areas; quantification of the MRS signals demonstrated a statistically significant decrease of the Cho/Cr ratio in the frontal and thalamic areas but not in the temporal area for patients with Cushing's syndrome. The largest decrease in Cho/Cr was measured in the thalamic area of patients with a Cushing's syndrome secondary to an adrenal disease. No statistically significant changes in the NAA/Cr ratio were measured in any of the areas studied. These results suggest that the quantification of choline levels could be helpful for monitoring the cerebral metabolite alterations in patients with hypercortisolism.     

磁共振波谱评价大脑半球代谢物的偏侧优势

为了利用无创性的磁共振波谱成像技术研究大脑半球代谢物的非对称性,本研究对56例正常成年人行磁共振波谱成像,主要对双侧大脑半球的4个解剖区域:额叶、颞叶、枕叶及顶叶的代谢物天门冬氨酸(NAA)、肌酸(Cr)、胆碱(Cho)进行测量,并以Cr为内参照物比较NAA和Cho相对含量(NAA/Cr、Cho/Cr)的侧别差异。结果表明:双侧额叶之间的NAA/Cr存在显著性差异,而Cho/Cr无显著性差异;在双侧颞叶之间,这2种比值均存在显著性差异;双侧枕叶之间Cho/Cr存在显著性差异,而NAA/Cr无显著性差异;双侧顶叶之间的NAA/Cr存在显著性差异,而Cho/Cr无显著性差异。本研究结果提示双侧大脑半球的代谢物存在偏侧优势。     

1H magnetic resonance spectroscopy investigation of the dorsolateral prefrontal cortex in bipolar disorder patients

BACKGROUND: Magnetic resonance spectroscopy studies (MRS) reported abnormally low levels of N-acetylaspartate (NAA, a marker of neuronal integrity) in dorsolateral prefrontal cortex (DLPFC) of adult bipolar patients, suggesting possible neuronal dysfunction. Furthermore, recent MRS reports suggested possible lithium-induced increase in NAA levels in bipolar patients. We examined with in vivo (1)H MRS NAA levels in the DLPFC of adult bipolar patients. METHODS: Ten DSM-IV bipolar disorder patients (6 lithium-treated, 4 drug-free) and 32 healthy controls underwent a short echo-time 1H MRS session, which localized an 8 cm3 single-voxel in the left DLPFC using a STEAM sequence. RESULTS: No significant differences between the two groups were found for NAA, choline-containing molecules (GPC+PC), or phosphocreatine plus creatine (PCr+Cr) (Student t-test, p > 0.05). Nonetheless, NAA/PCr+Cr ratios were significantly increased in lithium-treated bipolar subjects compared to unmedicated patients and healthy controls (Mann-Whitney U-test, p < 0.05). LIMITATIONS: Relatively small sample size may have reduced the statistical power of our analyses and the utilization of a single-voxel approach did not allow for the examination of other cortical brain areas. CONCLUSIONS: This study did not find abnormally reduced levels of NAA in left DLPFC of adult bipolar patients, in a sample of patients who were mostly on medications. However, elevated NAA/PCr+Cr ratios were shown in lithium-treated bipolar patients. Longitudinal 1H MRS studies should further examine NAA levels in prefrontal cortex regions in untreated bipolar patients before and after mood stabilizing treatment.     

1H magnetic resonance spectroscopy at 3 T in cryptogenic and mesial temporal lobe epilepsy

The objectives of this work were to compare concentrations of N-acetylaspartate (NAA), glutamate (Glu), glutamine (Gln), Glx (=Glu + Gln), myo-inositol (mI), total creatine (Cre) and other metabolites in the temporal lobes of patients with mesial temporal lobe epilepsy (mTLE), cryptogenic TLE (cTLE), who show no abnormalities in high-resolution MRI, and healthy controls using single voxel (1)H MRS at 3 T. Twelve patients with mTLE, nine with cTLE and 22 controls were investigated using a short echo time STEAM protocol. Voxels were positioned bilaterally in the medial and lateral temporal lobes. Spectra were processed with LCModel. Significantly lower mean NAA were detected in mTLE patients (P < 0.001) and a trend towards lower NAA in cTLE patients compared to controls (P = 0.053). Glx was not different between groups. Estimates of Glu showed a different metabolic pattern in mTLE with elevated Glu in lateral compared with medial voxels on the ipsilateral side to seizure onset (P = 0.019). MI concentrations were significantly lower in cTLE (P < 0.001) and in mTLE patients (P = 0.005) compared with healthy controls. MI/Cre was significantly reduced in cTLE patients only (P = 0.004). The results confirm low NAA in mTLE and to a lesser extent in cTLE patients. MI and mI/Cre were identified as potential metabolic indicators of the epileptogenic area in cTLE.     

Regional proton magnetic resonance spectroscopy patterns in dementia with Lewy bodies

Magnetic resonance spectroscopy (MRS) characteristics of dementia with Lewy bodies (DLB) Alzheimer's disease (AD) and cognitively normal controls were compared. DLB (n = 34), AD (n = 35), and cognitively normal controls (n = 148) participated in a MRS study from frontal, posterior cingulate, and occipital voxels. We investigated DLB patients with preserved hippocampal volumes to determine the MRS changes in DLB with low probability of overlapping AD pathology. DLB patients were characterized by decreased N-acetylaspartate/creatine (NAA/Cr) in the occipital voxel. AD patients were characterized by lower NAA/Cr in the frontal and posterior cingulate voxels. Normal NAA/Cr levels in the frontal voxel differentiated DLB patients with preserved hippocampal volumes from AD patients. DLB and AD patients had elevated choline/creatine, and myo-Inositol/creatine in the posterior cingulate. MRS abnormalities associated with loss of neuronal integrity localized to the occipital lobes in DLB, and the posterior cingulate gyri and frontal lobes in AD. This pattern of MRS abnormalities may have a role in differential diagnosis of DLB and in distinguishing DLB patients with overlapping AD pathology.     

Effects of contrast material on the metabolite ratios in single-voxel MR Spectroscopy of intraaxial brain tumors

Aim

The purpose of our study was to determine whether the administration of contrast material affects the results of MR Spectroscopy (MRS) in different intraaxial brain tumors.

Materials and methods

Thirty-three patients (median range 46.72 ± 2.95, range 9–77) with intraaxial brain tumors underwent MRS before and 5 min after intravenous administration of gadolinium based contrast material at the standard dose of 0.1 mmol/kg (Gadodiamide or Gd-DOTA). Metabolite ratios (N-acetyl aspartate (NAA)/Creatine (Cr), Choline (Cho)/Cr, and NAA/Cho) were calculated.

Results

There was no significant difference between the pre and postcontrast MRS spectra as regards to NAA/Cr (p:0.4), Cho/Cr (p:0.2), and NAA/Cho (p:0.2) ratios obtained from the intraaxial brain tumors.

Conclusion

Contrast material administration did not change the metabolite ratios of MRS. Contrast administration would be useful in guiding voxel localization in MRS evaluation of intraaxial brain tumors.     

帕金森病大鼠模型额叶皮质的代谢及形态改变

目的：探讨帕金森病中大脑额叶皮质的形态及代谢改变。方法：大鼠实验组于6-OHDA毁损后用BIOSPEC47／30磁共振波谱仪(4．7T)，采用点分辨波谱法对双侧额叶皮质行H-MRS检测，分析该区N-乙酰天门冬氨酸／肌酸(NAA／Cr)和胆碱／肌酸(Cho／Cr)比值的变化，并用电镜观察该区神经元及突触的形态变化。结果：实验组大鼠损毁侧额叶皮质．NA．A／Cr比值显著低于对侧，对照组两侧无显著差别；Cho／Cr比值在两组的两侧相比均无显著差别。电镜观察显示：损毁侧额叶皮质的突触数量较对侧减少，突触前、后膜和突触小泡结构异常，典型突触结构消失，树突棘出现大片低电子密度区，细胞器消失。结论：帕金森病大鼠模型损毁侧额叶皮质内存在神经元缺失或突触数量的减少，突触结构异常及功能异常。     

Effects of normal aging and SCN1A risk‐gene expression on brain metabolites: evidence for an association between SCN1A and myo‐inositol

Previously reported MRS findings in the aging brain include lower N‐acetylaspartate (NAA) and higher myo‐inositol (mI), total creatine (Cr) and choline‐containing compound (Cho) concentrations. Alterations in the sodium channel voltage gated type I, alpha subunit SCN1A variant rs10930201 have been reported to be associated with several neurological disorders with cognitive deficits. MRS studies in SCN1A‐related diseases have reported striking differences in the mI concentrations between patients and controls. In a study on ‘healthy aging’, we investigated metabolite spectra in a sample of 83 healthy volunteers and determined their age dependence. We also investigated a potential link between SCN1A and mI. We observed a significantly negative association of NAA (p = 0.004) and significantly positive associations of mI (p ≤ 0.001), Cr (p ≤ 0.001) and Cho (p = 0.034) with age in frontal white matter. The linear association of Cho ends at the age of about 50 years and is followed by an inverted ‘U’‐shaped curve. Further, mI was higher in C allele carriers of the SCN1A variant rs10930201. Our results corroborated the age‐related changes in metabolite concentrations, and found evidence for a link between SCN1A and frontal white matter mI in healthy subjects. Copyright © 2013 John Wiley & Sons, Ltd.     

Quantitative proton magnetic resonance spectroscopy of the bilateral frontal lobes in patients with bipolar disorder.

BACKGROUND: Using 31P and 1H magnetic resonance spectroscopy (MRS) we previously reported that phosphocreatine was decreased in the left frontal lobe and choline-containing compounds were increased in the basal ganglia in the depressive state in patients with bipolar disorder. We applied quantitative 1H-MRS for further characterization of biochemical alteration in the frontal lobes of bipolar patients. METHODS: Twenty-three bipolar patients and 20 normal controls were examined by 1H-MRS with a 1.5T MR system. All patients were examined in the euthymic state, and eight patients were also examined in the depressive state. Volumes of interest of 2.5 x 2.5 x 2.5 cm were selected in the left and right frontal lobes. Absolute concentrations of N-acetyl-1-aspartate, creatine plus phosphocreatine, and choline-containing compounds were calculated from each metabolite peak. RESULTS: Creatine concentration in the left frontal lobe in bipolar patients in the depressive state was significantly lower than that in the euthymic state. Creatine concentration in the right frontal lobe in the male patients was significantly higher than that in the female patients and a similar trend was also found in the control subjects. CONCLUSIONS: We found a state-dependent change of creatine metabolism in the left frontal lobe of bipolar patients. The present results are compatible with our previous report of decreased phosphocreatine measured by 31P-MRS in the left frontal lobe in bipolar disorder. We also found an effect of gender on the creatine concentration. There may be a gender difference in creatine transport function into the brain.     

脑结构形态学改变是精神分裂症的遗传内表型

目的 通过对首发精神分裂症患者及其未患病同胞的磁共振成像脑结构分析,探讨遗传因素对脑结构改变的影响程度,为发现精神分裂症的遗传内表型提供实验依据.方法 采用优化的基于体素的形态学研究方法对15例首发精神分裂症患者、19名首发精神分裂症患者未患病同胞及38名正常对照的大脑磁共振图像进行处理,采用一般线性模型进行统计分析.结果 与正常对照组相比,患者组在双侧颢叶、双侧枕叶、左侧岛叶、左侧额叶额上回及右豆状核苍白球灰质有明显减少;在双侧顶叶及双侧边缘叶扣带回灰质增加;未患病同胞组在右侧颞叶、双侧枕叶、左侧岛叶及左侧额叶中央前回等区域灰质明显减少;在左侧顶叶及双侧小脑后叶灰质增加.患者较同胞左侧顶叶楔前叶灰质有增加,未发现两者其他区域存在明显差异.结论 精神分裂症患者及其同胞存在相似的脑结构异常,遗传因素可能是导致精神分裂症脑结构异常的重要因素,提示脑结构形态学改变是精神分裂症的遗传内表型.