Scenium软件研究不同性别正常人脑葡萄糖代谢随年龄变化的规律

目的：应用Scenium软件分析正常人脑PET图像,研究不同性别人脑葡萄糖代谢随年龄变化的规律。资料与方法收集493例男性和273例女性健康体检者的脑PET图像,按年龄将不同性别体检者分为21~30岁组、31~40岁组、41~50岁组、51~60岁组、61~70岁组、71~82岁组。应用Scenium软件对所得脑PET图像进行归一化并勾画脑区,获得各脑区标准摄取值（SUV）的平均值,比较不同性别及不同年龄组间各脑区葡萄糖代谢水平的差异。结果男性不同年龄组间多数脑区葡萄糖代谢差异有统计学意义（F=2.580~5.316, P<0.05）,仅右侧内侧颞叶和小脑差异无统计学意义（F=1.611~1.935, P>0.05）;而女性不同年龄组间各脑区葡萄糖代谢差异无统计学意义（F=0.721~1.706, P>0.05）。男性31~40岁组脑代谢水平达到最高峰,51~60岁组脑代谢水平降低最明显,降低区以扣带回、距状裂及周围皮质最显著;而61岁以后脑代谢水平趋于稳定。女性31~40岁组脑代谢水平有显著的高峰,其后随年龄增加,脑代谢无明显降低。结论正常人脑葡萄糖代谢40岁以后随年龄增加呈非匀速性下降趋势,男性随年龄增加脑功能代谢降低较明显,51~60岁时最为显著,而女性随年龄增加脑功能代谢降低不明显。     

Wilson病脑局部葡萄糖代谢变化的18F-FDG PET研究

目的 研究肝豆状核变性(即Wilson病,WD)患者脑局部葡萄糖代谢变化特征.方法 对13例伴有神经系统症状的WD患者和12名健康对照者进行脑18F-脱氧葡萄糖(FDG)PET静态显像,采用视觉分析、半定量分析和统计参数图(SPM)分析方法判断FDG PET显像结果.采用SPSS11.0软件进行统计学处理,将WD患者组与健康对照组进行组间统计分析.结果 WD患者FDGPET脑静态显像示双侧豆状核和尾状核放射性摄取较对照组对称性减低,前者比后者更明显;大脑皮质、丘脑、小脑放射性分布基本均匀、对称.WD患者豆状核和尾状核与大脑皮质放射性比值(0.95±0.05和1.02±0.06)明显低于对照组(1.26±0.05和1.17±0.05,t=15和8,P均<0.05),WD组豆状核与尾状核的放射性比值(0.93±0.06)明显低于对照组(1.09±0.06,t=9,P<0.05),丘脑和小脑与大脑皮质放射性比值与对照组差异无统计学意义(WD组:0.99±0.06和0.98±0.06,对照组:1.00±0.05和0.99±0.05;t=0.7和0.8,P均>0.05).结论 WD患者FDG PET脑静态显像特征为双侧豆状核和尾状核放射性摄取对称性减低,豆状核放射性摄取减低程度比尾状核更明显,FDG PET脑静态显像对鉴别诊断表现为神经系统异常的WD患者有价值.     

海马区脑功能连接网络随年龄变化的研究

目的建立基于脑功能连接网络的^18F-脱氧葡萄糖（FDG）PET脑图像分析方法,并利用该方法分析海马区功能连接网络随年龄的变化。方法将195名健康志愿者按年龄分为4组：31～40岁组50名,41～50岁组50名,51～60岁组50名,61—78岁组45名。分别采集静息状态下的脑部^18F-FDGPET图像,利用统计参数图（SPM）对图像进行归一化处理,提取功能脑区,并利用相关性分析,得到与海马区存在有功能连接的脑区,构建出海马的功能连接网络。结果各年龄组的海马-脑区功能连接存在差异。上述4个年龄组的左海马连接率分别为12％、11％、9％和8％,与年龄之间的相关系数（r）=-0．9726,P=0．0241;全海马的连接率分别为16％、11％、10％和10％,与年龄之间的r=-0．8157,P=0．1829。结论随着年龄的增加,海马区与其他脑区的连接功能明显下降,与海马的生理性变化相一致,表明脑功能连接的方法可以有效地用于^18F-FDGPET脑图像分析。     

肺内淋巴瘤的PET/CT影像表现分型

目的 总结恶性淋巴瘤(ML)肺侵犯的PET/CT影像学表现类型和特点,为正确诊断提供依据.方法 78例有肺侵犯的ML患者均经病理活组织检查证实,其中非霍奇金淋巴瘤(NHL)47例,霍奇金淋巴瘤(HL)10例,病理分型不明确的淋巴瘤21例.31例是因诊断不明确而;行PET/CT检查,发现并经病理检查确诊为ML,另47例已明确诊断者行PET/CT检查以了解肿瘤全身侵犯情况或有无复发、评价疗效.分析所有患者的PET/CT影像表现.结果 ML肺侵犯的影像表现形式各异,且同一病例可以同时出现不同的病变类型,大致可分为:(1)结节及肿块型(46例,含7例空洞型);(2)纤维索条及斑片型(29例);(3)胸膜心包侵犯型(23例);(4)双肺弥漫型(12例);(5)节段性或全肺不张型(9例);(6)环绕支气管肺门型(7例).除全身淋巴结组织和肺侵犯以外,还有其他部位的累及:骨皮质和骨髓内5例,胃3例,皮下软组织3例,乳腺1例,肾1例,肝1例,喉部1例.结论 PET/CT可以较准确地发现ML对肺的侵犯,显示病灶大小、形态和分布及肿瘤活性,为淋巴瘤的诊断和准确分期提供帮助.     

不同程度阿尔茨海默病PET脑代谢减低的SPM研究

目的 以统计参数图(SPM)为方法、其输出的脑代谢减低范围大小为指标,探讨不同程度阿尔茨海默病(AD)患者PET显像脑葡萄糖代谢减低区的大小和范围.方法 AD组27例,均符合精神障碍诊断和统计工作手册(DSM-Ⅳ-R)中的AD诊断标准,行简易智能量表(MMSE)检查.根据MMSE评分将AD组分为轻度、中度和重度组,每组各9例.对照组9名,均为健康体格检查者.所有受检者静脉注射18F-脱氧葡萄糖(FDG)后行PET三维脑显像.在Matlab 6.5平台上,用SPM2软件对得到的PET图像进行预处理,设P值阈值为0.001,将全部AD患者以及轻、中、重度3个AD患者组分别与对照组进行组间统计分析.结果 与对照组比较,AD组于双侧顶叶、颞叶、额叶及扣带回出现代谢减低区,以k值(即满足P值要求的每一"块"异常脑区的像素值)为指标测量,轻度组减低区k值为929,其中额叶减低区k值为174;中度组k值为6743,额叶减低区k值为2712;重度组k值为24 678,额叶减低区k值为4981.脑白质及脑内灰质核团未见代谢减低.结论 使用SPM,以k值为指标,可对不同程度AD患者脑代谢减低区大小进行评价.随痴呆程度加重,受累脑区范围增加,额叶晚期受累严重.     

基于18F-FDG PET显像建立帕金森病脑代谢网络模式

目的 在PD患者中建立疾病相关脑代谢网络模式(PDRP),为PD早期诊断和鉴别诊断奠定基础.方法 对32例不同严重程度的PD患者和32名年龄、性别匹配的健康对照者分别行静息状态下18F-FDG PET脑显像,将2组的PET图像进行主成分分析(PCA)以获得PDRP.观察PDRP表达值与疾病严重程度[PD综合评分量表(UPDRS)运动功能评分和Hoehn&Yahr评分]之间的相关性.统计学比较采用两样本t检验和Pearson相关分析.结果 PDRP的特征表现为脑内壳核、苍白球、丘脑、脑桥、小脑和初级运动皮质的葡萄糖代谢增高,而运动前区和后顶叶的代谢相对减低.PD组的PDRP表达值明显高于对照组(1.605±0.655与0.000±0.523;t=10.829,P＜0.001),且与UPDRS运动功能评分呈明显正相关(r=0.760,P＜0.001).PDRP表达值与Hoehn&Yahr评分之间亦存在明显正相关(r=0.736,P＜0.001).结论 基于18F-FDG PET显像得到的PDRP可以有效区分PD患者和健康对照者,并反映病情的严重程度.     

18F-FDG PET/CT显像正常腹部消化器官的标准摄取值分析

目的分析^18F-脱氧葡萄糖（FDG）PET/CT显像正常腹部消化器官标准摄取值（SUV）的变化范围.方法60例要求行PET/CT检查的健康人,按体重7.77 MBq/kg静脉注射^18F-FDG,PET采集为三维模式,每个床位3 min.对腹部肝、胆囊、脾、胰腺、胃、盲肠、结肠和直肠进行半定量分析,各器官的SUV由横断面测量,准确定位时参考同机CT.结果正常腹部消化器官^18F-FDG摄取有较大差异,其中摄取较高者SUV平均值（SUVavg）依次为直肠、肝、乙状结肠、回盲部和脾、升结肠,SUV最大值（SUVmax）依次为直肠、乙状结肠、肝、回盲部、升结肠、脾.结论PET/CT显像能较好地识别腹部消化器官;熟悉正常腹部消化器官^18F-FDG摄取的差异,对判读图像十分重要.     

细支气管肺泡癌^18F—FDG PET／CT显像的代谢和形态特征

目的分析细支气管肺泡癌（BAC）在^18F-脱氧葡萄糖（FDG）PET／CT图像中的代谢和形态结构特征,并与非细支气管肺泡型腺癌（non—BAC AC）的显像结果进行比较,探讨PET／CT在BAC诊断及鉴别诊断中的价值。方法回顾性分析经病理检查确诊的32例BAC及55例non—BAC AC的FDG PET／CT显像资料。测量病灶最大标准摄取值（SUVmax）,分析病灶位置、形态及边界、密度分布及其他典型CT结构征象。统计分析比较2组的平均SUVmax,评价与肿瘤分型有关的CT征象,比较单独PET、CT及PET和CT联合诊断的准确性。采用SPSS12．0软件对数据行t检验、McNemar检验、Fisher精确检验等。结果BAC组共47个病灶,non—BACAC组共63个病灶,组间SUVmax差异有统计学意义（1．51±0．17与6．28±3．04,t=-10．374,P〈0．0001）。BAC组纯磨玻璃密度影（45％的病灶,21／47）是相关的CT征象（Fisher精确检验,P〈0．0001）。结合PET代谢和CT解剖结构特征的联合诊断准确性与单独PET或CT对比,差异均有统计学意义（P=0．001和0．039）,诊断准确性分别为88％（28／32）、47％（15／32）和66％（21／32）。结论理解FDG PET／CT显像中BAC的代谢和形态结构特征,有利于提高诊断准确性。如动态观察中呈持续的CT磨玻璃密度影,即使低FDG摄取,也要考虑BAC可能。     

FDG PET／CT代谢体积对食管癌术后预后的预测价值

目的研究食管癌患者^18F-FDG PET／CTMTV与预后的关系。方法回顾性分析2004年3月至2008年3月行^18F—FDG PET／CT检查的49例Ⅰ—Ⅳa期的食管癌患者,均经病理检查证实,随访资料完整。患者均行食管癌切除术,随访截止至2009年11月,中位随访时间为29（8～57）个月。应用Kaplan—Meier法及Cox比例风险模型分析年龄、性别、肿瘤位置、肿瘤组织分化程度、PET／CT示肿瘤长径、美国肿瘤联合会（AJCC）分期、转移淋巴结个数、原发灶SUVmax及MTV与预后的关系。结果在单因素分析中,仅AJCC分期[χ^2=16．206,危险比（HR）=1．177,P〈0．001）,淋巴结分期（N）（χ^2=9．536,HR=10．833,P=0．002）,浸润深度（T）（χ^2=5．810,FIR=2．397,P=0．016）,淋巴结转移个数（χ^2=11．423,HR=1．567,P=0．001）、MTV（χ^2=3．872,HR=2．433,P=0．049）对预后存在预测作用。对以上变量行多因素分析,仅AJCC分期及MTV是独立的预后因子（r=4．525,HR=1．170,P=0．033;χ^2=4．875,HR=3．071,P=0．027）。Kaplan-Meier生存分析显示术前低MTV组比高MTV组的生存率高（Log—rank检验,χ^2=4．186,P=0．041）。结论MTV与食管癌术后患者的预后密切相关。对于高MTV患者,术后可能需要接受更加积极的治疗。     

鼻咽癌PET/CT影像表现及临床价值

目的研究鼻咽癌及其颈部淋巴结转移的PET／CT影像表现。方法初诊鼻咽癌患者51例、鼻咽部炎症患者14例及鼻咽癌治疗后患者36例。皆行^18F-脱氧葡萄糖（FDG）PET／CT显像。鼻咽部炎症患者和鼻咽癌治疗后患者临床随访时间皆〉6个月，淋巴结随访时间6～14个月。结果①51例鼻咽癌初诊患者和14例鼻咽部炎症患者的PET和CT影像表现差异明显。以鼻咽部软组织肿块（或组织增厚）处PET呈结节状、块状代谢增高为鼻咽癌PET／CT诊断标准，则灵敏度为96．0％，特异性为85．7％。PET／CT在鼻咽癌病灶的定位、病灶边界的确定及显示病灶对周围组织的侵犯方面优于PET和CT。②36例鼻咽癌治疗后患者，以鼻咽部软组织肿块（或组织增厚）处PET呈结节状或块状代谢增高为PET／CT诊断鼻咽癌复发、残余的标准，而以鼻咽部组织增厚作为CT诊断鼻咽癌复发、残余的标准，则PET／CT和CT对复发、残余病灶的检出灵敏度分别为84．6％和92．3％．特异性分别为91．3％和56．5％，假阳性率分别为8．6％和43．4％。③87例鼻咽癌患者中，6l例有颈部淋巴结增大，PET／CT和MRI诊断淋巴结转移的灵敏度分别为91．8％和88．8％（P〉0．05），特异性分别为82．2％和51．1％（P〈0．05）。结论PET／CT显像在诊断鼻咽癌及其淋巴结转移和复发方面优于单纯PET和CT。     

Cerebral glucose metabolism change in patients with complex regional pain syndrome: a PET study

Purpose The aim of this study was to examine abnormalities of the central nervous system in patients with chronic pain who were diagnosed with complex regional pain syndrome (CRPS). Materials and methods Brain activity was assessed using ¹⁸F-fluorodeoxyglucose positron emission tomography. The data collected from 18 patients were compared with data obtained from 13 normal age-matched controls. Results Our results showed that glucose metabolism was bilaterally increased in the secondary somatosensory cortex, mid-anterior cingulated cortex (ACC) or posterior cingulated cortex (PCC) (or both), parietal cortex, posterior parietal cortex (PPC), and cerebellum as well as in the right posterior insula and right thalamus in our patients. In contrast, glucose metabolism was reduced contralaterally in the dorsal prefrontal cortex and primary motor cortex. Glucose metabolism was bilaterally elevated in the mid-ACC/PCC and the PPC, which correlated with pain duration. Conclusion These data suggested that glucose metabolism in the brains of patients with CRPS changes dramatically at each location. In particular, glucose metabolism was increased in the areas concerned with somatosensory perception, possibly due to continuous painful stimulation.     

Factor analysis of regional cerebral glucose metabolic rates in healthy men

Cerebral glucose utilization measured with fluorine-18-fluoro-2-deoxy-D-glucose is characterized by considerable variability both among different persons and for the same person examined on different occasions. The goal of this study was to explore whether some regions of the brain were more variable than others with respect to glucose utilization and whether there was a pattern in their covariance. The global and regional cerebral utilization of glucose was measured in 12 healthy young volunteers on 3 or 4 occasions. In all, 24 regions were examined. The interrelation of the glucose utilization rates of the brain regions was investigated by factor analysis of the metabolic rates. Some 70% of the total variance was attributable to only 1 factor, while 80% of the total variance could be attributed to 2 factors. Regions making up the first factor were the frontal and temporal cortex, cingulate gyrus, caudate nucleus, thalamus and putamen. These regions are functionally related to the limbic system. Regions of the second factor were the parietal cortex, occipital cortex and cerebellum, regions more clearly related to sensory and motor functions. The 2-factor pattern was highly reproducible, being found with different algorithms for factor extraction and rotation. Under resting conditions, the variance of cerebral metabolism seems to be primarily related to regions which are closely involved with the limbic system. Cortical regions involved primarily in motor and sensory functions have less influence on the variance. Offprint requests to: Z. Szabo     

Imaging of regional metabolic activity by 18F-FDG/PET in rats with transient cerebral ischemia

Changes in regional metabolic activities induced by middle cerebral artery occlusion (MCAO) can influence patient outcome. Our aim was to demonstrate in a rat model that ¹⁸F-FDG with positron emission tomography (PET) imaging is a quantitative, reproducible approach for identifying acute and sub-acute metabolic variations in infarct regions. We found that imaging with ¹⁸F-FDG/PET enabled detection and quantification of ischemia-induced metabolic deficits and provided a sensitive and reliable means of assessing cerebral ischemic lesions compared with conventional neurological scoring systems in rodents.     

Measurement of regional cerebral blood volume using the EMI 1010 scanner.

Regional cerebral blood volume (rCBV) was measured in 14 patients with normal CT scans. An EMI CT 1010 scanner was used in combination with a computer subtraction technique. The mean CBV in the cortex was 5.0 ml/100 ml of tissue and 2.2 in the white matter. Regional differences were not significant and no difference was found between the right and left hemispheres.     

Regional cerebral glucose metabolic abnormality in Prader-Willi syndrome: A 18F-FDG PET study under sedation.

Prader-Willi syndrome (PWS) is a genetic disorder caused by the nonexpression of paternal genes in the PWS region of chromosome 15q11-13 and is the most common cause of human syndromic obesity. METHODS: We investigated regional brain metabolic impairment in children with PWS by 18F-FDG PET. Sixteen children with PWS (9 males, 7 females; mean age +/- SD, 4.2 +/- 1.1 y) and 7 healthy children (4 males, 3 females; mean age +/- SD, 4.0 +/- 1.7 y) underwent brain 18F-FDG PET in the resting state. The images of PWS children were compared using statistical parametric mapping analysis with those of healthy children in a voxelwise manner. RESULTS: Group comparison showed that children with PWS had decreased glucose metabolism in the right superior temporal gyrus and left cerebellar vermis, regions that are associated with taste perception/food reward and cognitive and emotional function, respectively. Metabolism was increased in the right orbitofrontal, bilateral middle frontal, right inferior frontal, left superior frontal, and bilateral anterior cingulate gyri, right temporal pole, and left uncus, regions that are involved in cognitive functions related to eating or obsessive-compulsive behavior. Interestingly, no significant metabolic abnormality was found in the hypothalamus, the brain region believed to be most involved in energy intake and expenditure. CONCLUSION: This study describes the neural substrate underlying the abnormal eating behavior and psychobehavioral problems of PWS.     

Stability of regional cerebral glucose metabolism in the normal brain measured by positron emission tomography

Cerebral glucose utilization (LCMRGI) was measured using the [18F]fluorodeoxyglucose method with PET in two groups of ten healthy young volunteers, each scanned in a resting state under different methodological conditions. In addition, five subjects had a second scan within 48 hr. Mean hemispheric values averaged 45.8 +/- 3.3 mumol/100 g/min in the right cerebral hemisphere and 47.0 +/- 3.7 mumol/100 g/min in the left hemisphere. A four-way analysis of variance (group, sex, region, hemisphere) was carried out on the results using three different methods of data manipulation: (a) the raw values of glucose utilization, (b) LCMRGI values "normalized" by the mean hemispheric gray matter LCMRGI value, and (c) log transformed LCMRGI values. For all analysis techniques, significantly higher LCMRGI values were consistently seen in the left mid and posterior temporal area and caudate nucleus relative to the right, and in the right occipital region relative to the left. The coefficient of variation of intrasubject regional differences (9.9%) was significantly smaller than the coefficient of variation for regions between subjects (16.5%). No differences were noted between the sexes and no effect of repeat procedures was seen in subjects having multiple scans. In addition, inter-regional LCMRGI correlations were examined both in values from the 20 normal subjects, as well as in a set of hypothetical "abnormal" values. Results were compared with those reported from other PET centers; despite certain methodological differences, the intersubject and inter-regional variation of LCMRGI is fairly constant.     

Measurement of cerebral glucose metabolic rates in the anesthetized rat by dynamic scanning with 18F-FDG, the ATLAS small animal PET scanner, and arterial blood sampling.

Rodent models and genetically altered mice have recently become available to study many human diseases. A sensitive and accurate PET scanner for small animals would be useful to evaluate treatment of these diseases in rodent models. To examine the feasibility of performing quantitative PET studies, we performed dynamic scans with arterial blood sampling in anesthetized rats with the ATLAS (Advanced Technology Laboratory Animal Scanner) small animal PET scanner developed at the National Institutes of Health and (18)F-FDG and compared activities determined by PET scanning with those obtained by direct tissue sampling. METHODS: Dynamic PET scans after a bolus of approximately 48 MBq (1.3 mCi) (18)F-FDG were performed in rats anesthetized with isoflurane. Arterial blood sampling was performed throughout the scanning period. At 60 min the rat was killed, and the brain was rapidly removed and dissected into 5 structures (thalamus [TH], cortex [CX], brain stem [BS], cerebellum [CB], and half brain). Activity in the tissue samples was compared with the mean activity of the last 5 min of calibrated PET data. RESULTS: Plasma activity peaked at approximately 0.2 min and then cleared rapidly. Brain activity initially rose rapidly; the rate of increase then progressively slowed until activity was approximately constant between 30 and 60 min. Recovery coefficients (MBq/mL in PET images)/(MBq/mL in tissue samples) were 0.99 +/- 0.04, 0.90 +/- 0.19, 1.01 +/- 0.24, 0.84 +/- 0.05, and 1.01 +/- 0.17, respectively, in TH, CX, BS, CB, and half brain (mean +/- SD, n = 6-9). Cerebral glucose utilization determined by Patlak analyses of PET data measured 30-60 min after injection of (18)F-FDG was 31.7 +/- 5.2, 23.9 +/- 4.8, 29.9 +/- 5.0, 39.3 +/- 7.3, and 28.1 +/- 4.6 micro mol/100 g/min (mean +/- SD, n = 9) in TH, CX, BS, CB, and whole brain, respectively. These results are consistent with a previous (14)C-deoxyglucose study of the isoflurane-anesthetized rat. CONCLUSION: Expected values for glucose metabolic rates and recovery coefficients near unity suggest that quantitatively accurate dynamic (18)F-FDG brain imaging can be performed in the rat with arterial blood sampling and the ATLAS small animal PET scanner.     

正常成人多层螺旋CT灌注成像的脑血流动力学研究

目的　探讨多层螺旋CT灌注成像 (MSCTPI)技术在正常人脑血流动力学中的应用。方法　选择 30例正常成年人行常规头颅CT平扫后 ,再行MSCTPI检查。在常规轴面CT扫描后选取基底节及其相邻层面 ,经肘静脉团注对比剂 ,同时开始连续 4 0s的双层动态扫描 ,重建的 80幅动态图像使用CT脑灌注软件包进行处理 ,获得灌注图像 ,测量所选脑内感兴趣区的血流量、血容量及达峰时间 ,并对其进行定量分析。结果　MSCTPI显示正常成年人脑灰质灌注高于脑白质 ,脑灰质的平均血流量、平均血容量、达峰时间分别为 (5 0 6± 9 0 )ml·min-1·10 0 g-1、(5 7 8± 9 1)ml·min-1·10 0 g-1、(10 6± 1 6 )s,脑白质分别为 (2 2 7± 8 6 )ml·min-1·10 0 g-1、(30 8± 9 8)ml·min-1·10 0g-1、(12 9± 2 6 )s。结论　MSCTPI技术为测量脑血流动力学指标提供了一种新的影像学方法。     

Cerebellar glucose consumption in normal and pathologic states using fluorine-FDG and PET

We studied cerebellar metabolism in 118 subjects including young and elderly controls and patients suffering from stroke, supratentorial brain tumor and Alzheimer's disease using fluorine-18 fluorodeoxyglucose ([18F]FDG) and position emission tomography (PET). Alzheimer's disease and normal aging did not alter mean cerebellar metabolism. In stroke and tumor mean cerebellar metabolism was lower in the hemisphere contralateral to the supratentorial lesion. In tumor bilaterally significant reductions in absolute cerebellar metabolism also were noted, unlike stroke. Primary sensory stimulation did not alter absolute or relative cerebellar metabolism. These results show that absolute and relative values for cerebellar metabolism vary depending on the process under study. Thus analysis schemes employing normalization of regional metabolic data to cerebellar values may be subject to error.