全面性发育迟缓患儿磁共振波谱与认知功能的相关性研究

目的探讨不同程度全面性发育迟缓患儿额叶、海马区代谢物特点,并探索其与认知功能水平的相关性。方法纳入66例头颅磁共振成像无明显异常的全面性发育迟缓患儿,采用Gessell发育诊断量表评估认知功能水平,并根据发育商(DQ)分为轻度发育迟缓组(24例)、中度发育迟缓组(20例)、重度发育迟缓组(22例);利用磁共振波谱(MRS)技术,选择双侧额叶白质、海马区为感兴趣区,计算其中N-乙酰天门冬氨酸/肌酸(NAA/Cr)、胆碱/肌酸(Cho/Cr)、NAA/(Cho+Cr)的相对值,比较轻度、中度、重度发育迟缓组的代谢物水平,并探讨其与病情程度、认知功能的相关性。结果三组患儿的双侧额叶白质以及海马区NAA/Cr、Cho/Cr、NAA/(Cho+Cr)水平的差异均无统计学意义(P0.05)。各代谢物相对水平与病情程度、认知功能均无显著相关性(P0.05)。结论选择额叶白质及海马区行MRS检查,对评估全面性发育迟缓患儿的疾病严重程度及认知功能的价值不大。     

氢质子磁共振波谱和磁共振弥散加权成像早期诊断新生儿缺氧缺血性脑病的价值探讨

目的探讨磁共振弥散加权成像(DWI)的表观弥散系数值(ADC)和氢质子磁共振频谱(1H-MRS)在评价足月新生儿缺氧缺血性脑病(HIE)中的临床价值。方法32例足月HIE患儿和同期10例健康足月新生儿生后10d内行DWI和1H-MRS扫描,记录代谢产物1H-MRS波峰下面积和ADC值,并进行比较。结果(1)HIE组右侧基底节和额叶的乳酸/肌酸比值(Lac/Cr)较对照组升高,N乙酰天门冬氨酸/肌酸比值(NAA/Cr)、胆碱/肌酸比值(Cho/Cr)较对照组降低,差异有统计学意义(P均<0.05);轻度、中度、重度HIE组右侧基底节和额叶的Lac/Cr比值逐渐升高,均高于对照组(P均<0.05),右侧基底节NAA/Cr、Cho/Cr比值逐渐降低,均低于对照组(P均<0.05)。HIE的临床分度与右侧基底节和额叶的Lac/Cr呈正相关,与右侧基底节的NAA/Cr、Cho/Cr呈负相关。(2)HIE组左右两侧豆状核及右侧额叶深部白质ADC值较对照组降低,差异有统计学意义(P<0.05);HIE临床分度与左右两侧豆状核及右侧额叶深部白质的ADC值为负相关。(3)右侧基底节NAA/Cr与左右两侧豆状核ADC值呈正相关。...     

氢质子磁共振波谱和磁共振弥散加权成像早期诊断新生儿缺氧缺血性脑病的价值探讨

目的 探讨磁共振弥散加权成像(DWI)的表观弥散系数值(ADC)和氢质子磁共振频谱(1H-MRS)在评价足月新生儿缺氧缺血性脑病(HIE)中的临床价值.方法 32例足月HIE患儿和同期10例健康足月新生儿生后10 d内行DWI和1H-MRS扫描,记录代谢产物1H-MRS波峰下面积和ADC值,并进行比较.结果 (1)HIE组右侧基底节和额叶的乳酸/肌酸比值(Lac/Cr)较对照组升高,N乙酰天门冬氨酸/肌酸比值(NAA/Cr)、胆碱/肌酸比值(Cho/Cr)较对照组降低,差异有统计学意义(P均<0.05);轻度、中度、重度HIE组右侧基底节和额叶的Lac/Cr比值逐渐升高,均高于对照组(P均<0.05),右侧基底节NAA/Cr、Cho/Cr比值逐渐降低,均低于对照组(P均<0.05).HIE的临床分度与右侧基底节和额叶的Lac/Cr呈正相关,与右侧基底节的NAA/Cr、Cho/Cr呈负相关.(2)HIE组左右两侧豆状核及右侧额叶深部白质ADC值较对照组降低,差异有统计学意义(P<0.05);HIE临床分度与左右两侧豆状核及右侧额叶深部白质的ADC值为负相关.(3)右侧基底节NAA/Cr与左右两侧豆状核ADC值呈正相关.结论 DWI和1H-MRS对新生儿HIE的临床诊断有重要临床意义,将两者结合可更好地评价脑损伤的严重程度,为临床诊疗提供有力依据,值得深入研究及推广.     

MRI和DTI评价早产儿脑白质髓鞘发育

目的 应用磁共振(MRI)、磁共振弥散张量成像(DTI)研究早产儿脑白质髓鞘发育的特点。方法 胎龄≤32周、出生体重<1 500 g的31例早产儿根据头部MRI检查分为早产脑损伤组(12例)和早产无脑损伤组(19例)。选取24例足月儿作为对照组。均于胎龄或纠正胎龄37~40周之间完成头部MRI及DTI检查。测定3组相同感兴趣区的部分各向异性参数(FA)和表观扩散系数(ADC)。结果 早产脑损伤组内囊后肢FA值小于早产无脑损伤组和足月对照组 (P < 0.05);早产脑损伤组和早产无脑损伤组的额叶白质和豆状核的FA值小于足月对照组 (P < 0.05);3组间枕叶白质的FA值差异无显著性 (P > 0.05)。早产脑损伤组和早产无脑损伤组内囊后肢、豆状核、枕叶白质、额叶白质的ADC值高于足月对照组 (P < 0.05)。结论 早产儿脑损伤容易出现内囊后肢深部脑白质髓鞘化障碍或延迟。早产儿至纠正胎龄足月时,无论有无脑损伤,脑周围白质及灰质成熟度均低于足月儿。     

氢质子磁共振波谱检测小儿热性惊厥及癫癎临床价值研究

目的 探讨氢质子磁共振波谱(proton maglletic resonance spectrpscopy,1H-MRS)检测在热性惊厥(febrile seizure,FS)及癫瘖(epilepsy,EP)中的临床应用价值及意义.方法 2006-2007年收治惊厥患儿共41例,其中FS组25例.其中单纯性热性惊厥(simple febrile seizure,SFS)组15例及复杂性热性惊厥(complex febrile sei-zure.CFS)组10例;EP组16例,按有无合并热性惊厥史分为伴有热性惊厥组7例和不伴热性惊厥组9例.对热性惊厥和癫癎患儿进行常规头颅磁共振(MRI)及颞叶海马区1H-MRS检查,并选择6例神经系统正常儿童作对照组.1H-MRS检测指标:N-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱(Cho)、谷氨酸-谷氨酰胺复合物(Glx)和乳酸(Lac)的信号强度,计算NAb/(Cho Cr)和Lac/Cr的比值,并进行比较.结果 头颅MRI检查结果:FS组及对照组均正常,EP组除1例髓鞘发育不良外余均正常.1H-MRS检查结果显示:NAA(Cho Cr)比值SFS组为0.71±0.05.CFS组为0.65±0.04,EP组为0.62±0.04(其中伴有热性惊厥史EP组为0.60±0.03,不伴有热性惊厥史的EP组为0.64±0.04),对照组为0.73±0.05.NAA/(Cho Cr)比值在CFS组与EP组之间无明显差异(P>0.05),但两组均低于对照组(P<0.01);CFS组明显低于SFS组及对照组(P<0.01),但后两者差异无统计学意义(P>0.05);伴有热性谅厥史的EP组低于不伴有热性惊厥史的EP组(P<0.05). Lac/Cr比值SFS组(0.32±0.21)和CFS组(0.63±0.30)不仅高于对照组(0.05±0.04)(P<0.05),也明显高于EP组(0.11±0.09)(P<0.05);CFS组Lac/Cr高于SFS组,P<0.01;EP组Lac/Cr与对照组比较无明显差异.结论 (1)NAA/(Cho Cr)比值是反映脑损伤的客观指标,该指标在CFS及EP患儿脑组织中下降,提示存在神经元丢失或功能失常.(2)Lac/Cr比值是反映脑急性缺氧的指标,该指标在SFS及CFS患儿脑组织中升高,提示惊厥过程中存在脑局部缺血,即使是短暂单次的惊厥发作亦存在脑损伤.(3)1H-MRS作为一项无创的检查,能更敏感地发现FS及EP惠儿的早期脑损伤.有助于弥补MRI的不足及其他有创检查的损伤,为FS及EP患儿治疗、评估预后提供客观依据.     

单纯性肥胖儿童血清胰岛素样生长因子-1水平的临床研究

目的探讨单纯性肥胖儿童是否存在胰岛素样生长因子-1(insulinlikegrowthfactor1,IGF1)水平的异常,为防治儿童单纯性肥胖开辟新的医学途径。方法检测并分析50例单纯性肥胖儿童、30例健康儿童血清胰岛素、IGF1水平及血压。结果与健康儿童比较,单纯性肥胖儿童血清胰岛素、收缩压、舒张压增高,差异有显著性(P<0.05)。肥胖的程度不同,血糖、胰岛素、IGF1水平亦不同。对照组、轻、中、重度肥胖组的血糖、胰岛素、IGF1水平差异有统计学意义(F=8.79～14.82,P均<0.05)。重度肥胖组儿童的血糖浓度高于对照组和轻度肥胖组(P<0.05),而IGF1水平低于其他三组;中、重度肥胖儿童血清胰岛素水平高于对照组及轻度肥胖组(P<0.05);单纯性肥胖儿童血压高于健康儿童(P<0.05),高胰岛素血症的肥胖儿童血压明显高于胰岛素正常的儿童(P<0.01)。高胰岛素血症肥胖儿童IGF1水平低于胰岛素正常的儿童(P<0.01)。结论单纯性肥胖儿童,尤其是重度肥胖儿童,存在高胰岛素血症、高血压、IGF1水平低下及高血糖;IGF1水平下降是单纯性肥胖儿童物质代谢紊乱的危险信号,是肥胖儿童未来心血管疾病、糖尿病等的又一危险因素。     

氢质子磁共振波谱在原发性癫癎中的应用研究

目的：应用氢质子磁共振波谱(proton magnetic resonance spectroscopy, 'H-MRS)检测癫癎患儿的脑组织生化代谢物,探讨'H-MRS在原发性癫癎中的临床应用价值及意义。方法：对33例原发性癫癎患儿（癫癎组,其中14例有热性惊厥史）和6例正常儿童（对照组）进行常规头颅MRI和颞叶海马区的'H-MRS检查。检测N-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱(Cho)和乳酸(Lac)的信号强度,计算并比较NAA/（Cho+Cr）和Lac/Cr的比值。结果：头颅MRI检查：除1例癫癎患儿表现为髓鞘发育不良外其余所有研究对象均无异常。'H-MRS检测：NAA/（Cho+Cr）比值在癫癎组为0.64±0.07,低于对照组(0.73±0.05)（P＜0.01）;同时伴有热性惊厥史的癫癎患儿为0.61±0.07,低于不伴有热性惊厥史的癫癎患儿（0.66±0.06）（P＜0.05）。癫癎组Lac/Cr比值与对照组差异无统计学意义。结论：'H-MRS作为一项无创的检查,能更敏感地发现癫癎患儿的早期脑损伤,为癫癎的诊断和评估预后提供客观依据。［中国当代儿科杂志,2010,12（6）：425-428］     

氢质子磁共振波谱在热性惊厥中的临床应用

目的应用氢质子磁共振波谱(1H-MRS)检测热性惊厥(FS)患儿脑组织生化代谢物,了解FS发作后脑损伤情况,探讨1H-MRS在FS中应用的意义。方法对25例FS患儿和6例神经系统正常儿童进行常规头颅MRI和颞叶海马区的1H-MRS检查。25例FS患儿中,15例为单纯性热性惊厥(SFS),10例为复杂性热性惊厥(CFS)。检测指标为N-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱(Cho)、谷氨酸-谷氨酰胺复合物(Glx)和乳酸(Lac)的信号强度,计算并比较NAA/(Cho Cr)和Lac/Cr的比值。结果头颅MRI检查结果为FS组及对照组均未显示异常。1H-MRS检测结果为NAA/(Cho Cr)比值,SFS组为0.71±0.05,CFS组为0.65±0.04,对照组为0.73±0.05,CFS组明显低于SFS组及对照组(Pa<0.01),但后二者之间无明显差异(P>0.05)。Lac/Cr比值SFS组(0.32±0.21)和CFS组(0.63±0.30)高于对照组(0.05±0.04)(Pa<0.05),且CFS组高于SFS组(P<0.01)。结论1H-MRS作为一项无创检查,能更敏感地发现FS患儿的早期脑损伤,为FS尤其是CFS患儿的治疗、评估预后提供客观依据。     

儿童肥胖症与内皮素及氧化低密度脂蛋白关系的探讨

目的探讨儿童肥胖所至动脉粥样硬化(AS)的早期报警指标。方法对32例中重度肥胖及20例健康正常体重儿童内皮素(ET)及氧化低密度脂蛋白(OX－LDL)进行测定。结果肥胖组ET及OX－LDL值分别高于对照组，P均＜0.01；肥胖组收缩压及舒张压均大于对照组，但P均＞0.05。其中10例肥胖儿童经6周综合减肥治疗，自身对比体重下降，P＜0.01；ET水平降低，P＜0.05；OX－LDL水平下降，P＜0.01。结论肥胖症儿童血ET与OX－LDL增高并随体重减低而减少；ET可作为早期AS的示警指标。     

核磁共振和核磁共振波谱结合粗大运动评定量表在儿童脑性瘫痪分度诊断的应用

目的 探讨头部核磁共振、核磁共振波谱以及粗大运动评定量表对儿童脑性瘫痪的分级诊断价值.方法 40例1.0～2.0周岁的健康儿童和42例1.1 ～2.0周岁的脑性瘫痪儿童为研究对象,对比正常儿童与脑性瘫痪患儿的MRI、MRS检测结果;根据核磁共振结果对脑性瘫痪进行分度,并用核磁共振波谱检测不同核磁共振分度的脑性瘫痪患儿脑内的NAA/Cr、CHO/Cr、LAC/Cr水平并分度;考察不同核磁共振和核磁共振波谱分度脑性瘫痪患儿的粗大运动评定量表得分情况.结果 核磁共振和核磁共振波谱均能有效区分脑性瘫痪患儿脑内的典型病变,脑内的NAA、Cr、Cho能被核磁共振波谱定量检测.不同核磁共振分度的患者脑内的NAA/Cr、CHO/Cr、LAC/Cr有所差异,重度患者与中度患者间的差异具有统计学意义(P＜0.05).脑性瘫痪的核磁共振波谱分度与核磁共振分度相符率不理想,但粗大运动评定量表评分表明各不同分度之间有差异(P＜0.05).结论 核磁共振和核磁共振波谱结合粗大运动评定量表可有效完善脑性瘫痪的分度诊断,这对不同类型儿童脑性瘫痪的临床治疗具有一定的指导意义.     

Serial 1H-MRS in GM2 gangliosidoses

GM2 gangliosidoses are a group of neuronal storage disorders caused by deficiency in the lysosomal enzyme hexosaminidase A. Clinically, the disease is marked by a relentless encephalopathy. Proton magnetic resonance spectroscopy (1H-MRS) provides in-vivo measurement of various brain metabolites including N-acetyl aspartate+N-acetyl aspartate glutamate (NAA), myo-inositol (mI), choline (Cho) and creatine (Cr). The NAA represents neuronal integrity while elevation in the mI reflects abnormal inflammation and gliosis in the brain tissue. An elevation in the Cho levels suggest cell membrane breakdown and demyelination. We report the clinical and laboratory data in two patients with GM2 gangliosidoses. Serial 1H-MRS evaluations were performed to drive metabolite ratios of NAA/Cr, mI/Cr and Cho/Cr. We acquired the data from four regions of interest (ROI) according to a standard protocol. The results documented a progressive elevation in mI/Cr in all four ROI in patient one and only one ROI (occipital gray matter) in patient 2. We also documented a decline in the NAA/Cr ratios in both cases in most ROI. These results were compared to six age-matched controls and confirmed statistically significant elevation in the mI in our cases. In conclusion, 1H-MRS alterations were suggestive of neuronal loss and inflammation in these patients. 1H-MRS may be a valuable tool in monitoring the disease progress and response to therapy in GM2 gangliosidoses. Elevation in the mI may prove to be more sensitive than the other metabolite alterations.     

Anterior cingulate and frontal lobe white matter spectroscopy in early childhood of former very LBW premature infants

Neurometabolic sequelae of children born at very LBW (VLBW) are not well characterized in early childhood. Proton magnetic resonance spectroscopy (1H-MRS) and developmental assessments were acquired from children age 18-22 mo (16 VLBW/7 term) and 3-4 y (12 VLBW/8 term) from the anterior cingulate and left frontal periventricular white matter. Metabolites obtained included combined N-acetylaspartylglutamate and N-acetylaspartate (NAA), total choline-containing compounds (Cho), combined glutamate and glutamine (Glx), combined creatine and phosphocreatine (Cr), myoinositol (mI), and the following ratios: NAA/Cr, Cho/Cr, Glx/Cr, mI/Cr, and NAA/Cho. Significant differences were present only in white matter: at 18-22 mo, NAA was decreased in VLBW children (p < 0.04), and at 3-4 y, VLBW children showed lower Cr (p < 0.01), lower NAA/Cho (p < 0.005), higher Glx/Cr (p < 0.02), and higher Cho/Cr (p < 0.005). On developmental testing, VLBW children scored lower on language expression (p < 0.05) and on the A-not-B test of early executive function (p < 0.01) at 18-22 mo and had lower verbal intelligence quotient (IQ) (p < 0.005), performance IQ (p < 0.04), and several measures of early executive function including the bear-dragon test (p < 0.004), gift delay (p < 0.07), and summary categorization score (p < 0.03) at 3-4 y. VLBW children may have neurometabolic and developmental abnormalities that persist at least through early childhood.     

Cerebral metabolite differences in adolescents with low birth weight: assessment with in vivo proton MR spectroscopy

Background Children with very low birth weight (VLBW) have a significantly increased risk of later neurodevelopmental problems, while infants born small for gestational age (SGA) at term are also at some risk of developing neurological impairment.Objective To investigate possible brain metabolite differences in adolescents with VLBW, SGA at term and controls by proton in vivo magnetic resonance spectroscopy (MRS) at 1.5 T.Materials and methods MR spectra were acquired from volumes localized in the left frontal lobe, containing mainly white matter (54 subjects). Peak areas of N-acetyl aspartate (NAA), choline (Cho) and creatine (Cr) were determined, and the peak area ratio of NAA to Cr, total Cho to Cr, or NAA to Cho calculated. Probabilistic neural network (PNN) analysis was performed utilizing the chemical shift region containing resonances from NAA, Cho and Cr as inputs.Results No significant difference in the peak area ratios could be found using the Kruskal-Wallis test. By application of PNN, a correct classification of 52 of the 54 adolescents with a sensitivity and specificity exceeding 93% for all groups was achieved.Conclusion Small, yet systematic, differences in brain metabolite distribution among the groups were confirmed by PNN analysis.     

Cerebral structure and metabolism and long-term outcome in small-for-gestational-age preterm neonates

In the present study, we compared brain development and metabolism of small-for-gestational-age (SGA) and appropriate-for-gestational-age (AGA) infants using proton magnetic resonance spectroscopy ((1)H-MRS). We tested the hypothesis that intrauterine growth retardation caused by placental insufficiency is associated with changes in cerebral metabolism and is followed by an adverse neurodevelopmental outcome at the age of 2 y. Twenty-six AGA and 14 SGA (birth weight

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磁共振波谱测定癫痫患儿脑内代谢变化及其临床意义的研究

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Metabolic Alterations and Neurodevelopmental Outcome of Infants with Transposition of the Great Arteries

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Neonatal hydrocortisone treatment related to 1H-MRS of the hippocampus and short-term memory at school age in preterm born children

Animal studies have shown that corticosteroids (dexamethasone) cause neuronal loss in the hippocampus and deficits in short term memory. Proton magnetic resonance spectroscopy can measure brain metabolites in vivo and give an indication of neuronal integrity. We investigated whether prolonged administration of hydrocortisone during the neonatal period for bronchopulmonary dysplasia (BPD) in preterm born children changes the metabolism in the hippocampus, measured at school age. Secondly, we investigated whether hippocampal metabolism and short-term memory and neurodevelopmental outcome are related. In this observational study 37 preterm born children (< or = 32 wk (range 25.0-33.0) and/or a birth weight < or = 1500 g) underwent proton spectroscopy of the hippocampus at school age. Eighteen children were treated with hydrocortisone for BPD (starting dose 5 mg/kg/d tapered over a minimum period of 22 d, median duration 28 d) and 19 never received corticosteroids during the perinatal period. N-acetyl aspartate/ Choline + Creatine/phosphocreatine (NAA/(Cho + Cr)) ratios were determined. A 15-word recall memory test and an IQ measurement were obtained on the same day. Hydrocortisone treated children were younger, lighter and sicker than their nonsteroid treated counterparts. Mean NAA/(Cho + Cr) ratios in the hippocampus were not significantly different in the hydrocortisone group compared with the non-steroid group. Performance on the 15-word memory test and IQ were similar in the two groups. There was no relation between NAA/(Cho + Cr) ratios and memory nor between NAA/(Cho + Cr) ratios and IQ. We conclude that hydrocortisone in the mentioned dose, administered in the neonatal period for BPD, does not appear to have any long-term effects on memory and/or hippocampal metabolism.     

Proton magnetic resonance spectroscopy ((1)H-MRS) of the brain following high-dose methotrexate treatment for childhood cancer

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A proton magnetic resonance spectroscopic study in juvenile absence epilepsy in early stages

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