P型多系统萎缩与帕金森病的18F-脱氧葡萄糖脑代谢比较

目的 研究P型多系统萎缩(multiple system atrophy,MSA-P)与帕金森病(Parkinson's disease,PD)的脑部葡萄糖代谢差异.方法 MSA-P患者15例,PD患者32例,无神经系统疾病的健康对照8名,进行18F-脱氧葡萄糖(FDG)PET检查.分别取尾状核、豆状核、丘脑、小脑、双侧额叶、双侧顶叶、双侧颞叶和双侧枕叶为感兴趣区(ROI).应用PET专用软件计算各ROI的FDG放射性同位素值,以颅内各部位ROI的18F-FDG代谢比值为指标.结果 MSA-P的额叶、颞叶、顶叶、纹状体、丘脑的18F-FDG脑代谢与健康对照和帕金森病相比呈现对称性下降;丘脑18F-FDG代谢高于纹状体以及额、顶叶皮质;18F-FDG代谢比值同侧豆状核与丘脑为0.493±0.085,同侧尾状核头与丘脑为0.453±0.079.PD的额、顶、颞叶皮质18F-FDG代谢分别高于纹状体、丘脑;纹状体高于丘脑,首发症状肢体对侧豆状核与丘脑18F-FDG代谢比值为1.131±0.113;基底节代谢不对称.MSA-P的豆状核与丘脑18F-FDG代谢比值,同PD的豆状核与丘脑18F-FDG代谢比值相比差异有统计学意义(P＜0.01).结论 MSA-P与帕金森病的葡萄糖代谢差异显著,可以应用18F-FDG PET检查作为鉴别诊断的重要方法之一.     

PET-CT显像剂在脑胶质瘤中的应用

脑胶质瘤是中枢神经系统发生率最高的恶性肿瘤。近年来,众多新型正电子显像剂的开发和应用在脑胶质瘤的诊断中展现了广阔的发展前景。本文对目前应用于脑胶质瘤的几种显像剂,如^18F-氟代脱氧葡萄糖（^18F-FDG）、^11C-蛋氨酸（^11C-MET）、^11C-胆碱（^11C-Cho）、^18F-多巴（^18F-FDOPA）、^18F-氟米索硝唑（^18F-FMISO）、18F-氟代脱氧胸腺嘧啶（^18F-FLT）等作一综述。     

早发性与迟发性阿尔茨海默病患者大脑葡萄糖代谢的差异

目的初步探讨早发性阿尔茨海默病（AD）与迟发性AD患者大脑葡萄糖代谢的差异。方法对9例早发性AD、14例迟发性AD患者及分别与其年龄相匹配的29名年轻健康对照者和11名老年健康对照者进行^18F-氟脱氧葡萄糖（^18F-FDG）PET脑显像。应用统计参数图对PET数据进行基于体素水平的图像分析。结果早发性AD组葡萄糖代谢相对于年轻对照组减低的脑区及其在Brodmann分区图（BA）的定位分别为双侧额上回（BA6，8）、额中回（BA6），左侧顶下小叶（BA39），右侧缘上回（BA40）、扣带回（BA31）等部位（P〈0．01）；迟发性AD组葡萄糖代谢相对于老年对照组葡萄糖代谢减低的脑区及其定位分别为双侧额上回（BA8）、额中回（BA6，8）、楔前叶（BA19）、右侧角回（BA39）等部位（P〈0．01）。结论尽管严重程度、病程及受教育水平相当，但是早发性AD患者大脑葡萄糖代谢减低的范围比迟发性AD更广泛，程度也更严重。不同发病年龄AD患者大脑葡萄糖代谢的差异可能是由于二者的认知储备能力不同所致。     

帕金森病痴呆患者的神经心理测试与18氟-氟代脱氧葡萄糖正电子发射断层摄影术脑显像分析

目的 研究帕金森病痴呆(PDD)患者的神经心理学特点及18氟-氟代脱氧葡萄糖(18F-FDG)PET脑代谢显像的影像学特征.方法 (1)对12例PDND患者、12例PDD患者和12名健康对照者运用蒙特利尔认知评估量表(MoCA)进行检查.(2)静脉注射18F-FDG后行PET脑代谢显像,获得12例PDND患者和12例PDD患者的PET图像.结果 (1)PDD组的MoCA总成绩(分)低于PDND组,其中MoCA子项目中的视空间与执行功能(1.50±1.08与4.25 ±0.87,t=-1.891)、注意(3.67±1.37与6.00 ±0.00,t’=-2.199)、语言(1.83 ±0.94与2.67±0.49,t'=-2.745)、抽象(0.67 ±0.65与1.75±0.45,t=-4.732)、延迟回忆(0.25 ±0.45与3.00±1.28,t’=-7.021)和定向(4.25±1.71与6.00±0.00,t’=-3.545)成绩低于PDND组,差异均具有统计学意义(均P＜0.05).PDD组MoCA总成绩低于健康对照组,差异具有统计学意义(15.10 ±3.82与28.10±1.16,t'=-11.280,P＜0.05).(2)18 F-FDG PET脑代谢显像:PDND组的大脑半球脑代谢不对称性轻度减低,PDD组的大脑半球脑代谢不对称性重度减低.结论 PDD表现为多认知域受损,以视空间与执行功能、注意、语言、抽象、延迟回忆和定向障碍较为严重.18F-FDG PET脑代谢显像检测对PDD的诊断可能有一定的帮助.     

中晚期帕金森病患者的脑功能影像研究

目的　探讨晚期帕金森病(PD)患者静止期18F 脱氧葡萄糖(FDG)正电子发射断层扫描(PET)脑代谢显像的影像学特征及其意义。方法　11例中晚期帕金森病患者,其中男5例,女6例;平均年龄(63 .5±3 .7)岁;Hoehn Yahr分级4. 1±0. 5;以11名年龄匹配的健康人为对照,经静脉注射FDG后行脑断层显像,获得两组人的脑局部葡萄糖代谢率,通过SPM99统计学软件进行数据分析,比较两组脑内代谢的差异。结果　与健康人相比,帕金森病患者丘脑、豆状核代谢增加(P<0 .05);双侧运动前区(BA6)、额中回及顶叶代谢减低(P<0. 05)。结论　帕金森病患者丘脑、豆状核代谢增加,其相应的运动区皮质代谢减低,帕金森病的这一脑内代谢特点有助于帕金森病的辅助诊断及对其发病机制的探讨。     

正电子发射断层成像/CT观察健康人空腹时不同器官对18F脱氧葡萄糖的摄取

背景：既往国内外研究中,主要针对肿瘤患者体内葡萄糖的摄取情况,而关于正常人在空腹状态下不同器官对葡萄糖的摄取作用研究很少。 目的：正电子发射断层成像/CT观察健康人在空腹状态下不同器官对18F脱氧葡萄糖的摄取情况,分析空腹时脑、肝、肾、心脏和骨骼肌组织在糖代谢中的相关性。 方法：31例健康成年人空腹抽血测肝肾功能、血糖和血脂,并行正电子发射断层成像/CT检查,测脑、心脏、肝、肾脏和骨骼肌的18F脱氧葡萄糖的平均标准摄入值以及最大标准摄入值。 结果与结论：空腹时脑皮质18F脱氧葡萄糖的平均标准摄入值约是心脏和肾脏的两三倍,是肝脏的4倍左右,是骨骼肌的15倍。肝脏平均标准摄入值与肾脏和骨骼肌的平均标准摄入值呈显著正相关(r=0.406,0.391,P=0.023,0.030),但肝脏的平均标准摄入值与心和脑的平均标准摄入值无相关性。结果提示空腹状态下脑组织对葡萄糖摄取最多,骨骼肌最少,心脏、肝脏和肾脏居中;空腹状态下肝脏与肾脏和骨骼肌之间对葡萄糖的代谢存在显著相关性。     

轻度认知功能障碍患者正电子发射计算机体层摄影术和神经心理学测定的初步研究

目的　探讨轻度认知功能障碍患者脑葡萄糖代谢与神经心理学特点及其相互关系。方法　采用正电子发射体层摄影术 (PET)、简易智能状态测定 (MMSE)、韦克斯勒记忆量表测定 (WMS)和总体衰退量表 (GDS)测定 10例轻度认知功能障碍 (MCI)患者和 10名健康志愿者 (HC)。结果 (1)MCI组MMSE[(2 4.6± 2 2 )分 ]、WMS[(6 9.4± 10 .4)分 ]分值低于HC组 [分别为 (2 8.9± 1.1)分和 (93.1± 9.0 )分 ;P〈0 .0 1];(2 )MCI组左侧眶回、右侧颞叶中回和右侧壳核的局部脑葡萄糖代谢率 (rCMRglc)较HC组低 (P〈0 .0 5～ 0 .0 1) ;(3)将年龄、受教育年限、MMSE、WMS与不同脑区用18F标记的脱氧葡萄糖放射性比值进行相关分析显示 ,与年龄呈负相关 (P〈0 .0 5或P〈0 .0 1)的脑区有 :眶回、左侧额上回、左侧额下回、颞叶中回、颞叶下回、左侧顶叶、左侧中央前回、右侧中央后回、左颞叶内侧皮质、左侧海马回、左侧海马旁回、右侧前扣带回、后扣带回、左侧杏仁核等。与文化程度呈正相关 (P〈0 .0 5或P〈0 .0 1)的脑区有 :左侧颞叶下回、中央前回、左侧中央后回等 ;而右侧壳核则呈负相关。与MMSE呈正相关 (P〈0 .0 5或P〈0 .0 1)的脑区有 :额下回、左侧颞叶上回、颞叶中回、颞叶下回、左侧顶叶、左侧中央前回、中央后回、颞叶内侧皮     

激素表达差异性垂体癌

目的报告1例原位和转移灶激素表达差异的垂体癌患者的临床诊断与治疗经过,以提高对该病的认识。方法与结果女性患者,50岁。临床主要表现为垂体腺瘤切除术后4个月眼部胀痛不适。MRI显示颅内多发异常信号,垂体形态欠规则,鞍区呈异常信号和强化影;PET-CT显示多发高摄取病灶。首次术后HE染色,肿瘤细胞弥漫性分布,呈圆形或多边形伴轻度异形,胞质中等量、嗜酸性,胞核圆形、染色质较细、核仁不明显,核分裂象易见,无坏死;免疫组织化学染色,肿瘤细胞分别表达P53、嗜铬素A,个别表达生长激素,Ki-67抗原标记指数约为80%,病理诊断为非典型垂体腺瘤。肿瘤复发转移后顶叶肿瘤活检术可见肿瘤浸润脑实质,肿瘤细胞弥漫表达生长激素,Ki-67抗原标记指数约为75%,病理诊断为转移性垂体癌。结论垂体癌为临床罕见的恶性垂体肿瘤,需结合影像学和术后组织病理学明确诊断。首选外科手术切除肿瘤灶,辅助术后放射治疗或药物化疗,患者多预后不良。     

致死性家族性失眠患者脑葡萄糖代谢分析

目的 研究致死性家族性失眠(fatal familial insomnia,FFI)患者脑葡萄糖代谢变化特征.方法 对病程分别为2个月的患者1和6个月的患者2以及20名健康对照者进行18F-脱氧葡萄糖(18F-fluorodeoxyglucose,18F-FDG)PET静态显像.采用视觉分析的方法判断2例患者脑代谢改变情况,然后利用统计参数图分析方法对每例患者和与其年龄相匹配的10名健康对照者进行组间分析,判断其代谢改变特征.结果 与10名年龄相匹配的健康对照组相比,患者1表现为明显的丘脑、顶叶、尾状核、后扣带回和前额叶的代谢减低(t＞2.82,P＜0.01).患者2表现为明显的丘脑、顶叶、后扣带回和前额叶的代谢减低,其代谢减低的范围和程度明显大于患者1(t＞2.82,P＜0.01),并伴有颞叶和枕叶代谢减低(t＞2.82,P＜0.01).结论 FFI患者脑葡萄糖代谢改变主要为双侧丘脑和大脑皮质代谢减低,大脑皮质所累及的范围和程度随病程发展而增大.18F-FDG PET显像对FFI的诊断和鉴别诊断具有一定的参考价值.     

~(18)F-FDG PET显像观察特发性快眼动睡眠期行为障碍患者脑葡萄糖代谢特点的研究

目的探讨~(18)F-FDG PET显像观察特发性快眼动睡眠期行为障碍(iRBD)患者脑葡萄糖代谢改变和iRBD脑葡萄糖代谢改变与病程间的相关性。方法纳入多导睡眠监测(PSG)确诊的iRBD患者20例(iRBD组)和年龄、性别匹配的健康对照者19例(对照组)。两组均行~(18)F-FDG PET脑显像。基于自动解剖标记模板将大脑划分为90个左右对称的脑区,计算各脑区葡萄糖代谢半定量值。对iRBD组和对照组各脑区葡萄糖代谢半定量值进行独立样本t检验;并对iRBD组脑葡萄糖代谢改变与病程行Pearson相关分析。结果 (1)与对照组比较,iRBD组的双侧背外侧额上回、双侧眶部额上回、双侧眶部额中回、双侧海马、双侧海马旁回、双侧杏仁核、左侧眶部额下回、左侧岛叶、左侧内侧与旁扣带脑回、左侧中央旁小叶、左侧苍白球的葡萄糖代谢半定量值均增高(P0.05);双侧距状裂周围皮质、双侧楔叶、双侧舌回、双侧枕上回、双侧枕中回、双侧枕下回、双侧角回、双侧颞上回、双侧颞中回、右侧颞横回的葡萄糖代谢半定量值均降低(P0.05)。Pearson相关分析结果,iRBD组双侧杏仁核、双侧颞上回、右侧楔叶、右侧枕上回、右侧颞横回、左侧海马、左侧颞中回的葡萄糖代谢半定量值与病程呈正相关(P0.05);而双侧眶部额上回、双侧眶部额中回、左侧中央旁小叶、左侧眶部额下回、左侧内侧和旁扣带回、右侧背外侧额上回、右侧海马旁回的葡萄糖代谢半定量值与病程呈负相关(P0.05)。结论 iRBD患者脑内存在疾病相关的葡萄糖代谢水平改变,有助于客观评估iRBD病情的变化。     

Fluorodeoxyglucose F18 positron emission tomography in a case of slowly progressive pure alexia

We describe a 71-year-old patient with slowly progressive pure alexia in which analysis of her fluorodeoxyglucose FDG-PET scan revealed an area of focal hypometabolism in the visual word form area. She presented with difficulty reading. Examination revealed pure alexia with preservation of other cognitive domains. Brain MRI revealed only slight atrophy. A Fluorodeoxyglucose F18 positron emission tomography scan revealed hypometabolism in the occipital cortex bilaterally, left greater than right, with normal metabolism elsewhere in the brain. This case highlights the utility of FDG-PET scan in evaluating focal neurodegenerative conditions before clear atrophy can be seen on MRI.     

18F-DG PET在癫痫外科手术中的评价

目的评估^18F-脱氧葡萄糖（^18F-DG）正电子发射X线体层照像术（PET）对癫痫外科治疗的指导意义。方法对22例顽同性癫痫的患者进行^18F-DGPET、长程脑电图（EEG）、MRI检查，并根据检查结果进行开颅手术治疗。手术后对切除组织进行病理检查，并对患者进行手术后随访评估。结果所有患者PET检查均为阳性，20例患者（90．9％）长程脑电图检查阳性，18例患者（81．8％）MRI检查阳性，20例患者（90．9％）手术后癫痫发作部分或完全缓解，2例患者（9．1％）无明显缓解。结论^18F-DGPET在癫痫灶定位方面的作用对手术有重要指导意义，术中皮质脑电图（ECoG）将有助于提高手术治疗的效果。     

Parametric mapping of [18F]fluoromisonidazole positron emission tomography using basis functions

In this study, we show a basis function method (BAFPIC) for voxelwise calculation of kinetic parameters (K₁, k₂, k₃, K_i) and blood volume using an irreversible two-tissue compartment model. BAFPIC was applied to rat ischaemic stroke micro-positron emission tomography data acquired with the hypoxia tracer [¹⁸F]fluoromisonidazole because irreversible two-tissue compartmental modelling provided good fits to data from both hypoxic and normoxic tissues. Simulated data show that BAFPIC produces kinetic parameters with significantly lower variability and bias than nonlinear least squares (NLLS) modelling in hypoxic tissue. The advantage of BAFPIC over NLLS is less pronounced in normoxic tissue. K_i determined from BAFPIC has lower variability than that from the Patlak–Gjedde graphical analysis (PGA) by up to 40% and lower bias, except for normoxic tissue at mid-high noise levels. Consistent with the simulation results, BAFPIC parametric maps of real data suffer less noise-induced variability than do NLLS and PGA. Delineation of hypoxia on BAFPIC k₃ maps is aided by low variability in normoxic tissue, which matches that in K_i maps. BAFPIC produces K_i values that correlate well with those from PGA (r²=0.93 to 0.97; slope 0.99 to 1.05, absolute intercept <0.00002 mL/g per min). BAFPIC is a computationally efficient method of determining parametric maps with low bias and variance.     

The sensitivity of 18-fluorodopa positron emission tomography and magnetic resonance imaging in Parkinson''s disease

Parkinson's disease (PD) as the most important movement disorder is characterized by a progressive loss of nigral dopamine neurons and a subsequent degeneration within several other transmitter systems. Functional brain imaging with positron emission tomography (PET) and the radiotracer 18-fluorodopa (FDOPA) is capable to quantify the deficiency of dopamine synthesis and storage within pre-synaptic striatal nerve terminals. Therefore, FDOPA-PET allows the diagnosis of PD in early disease stages and the differentiation of clinically unclear cases from other movement disorders, e.g. essential tremor. Additionally, FDOPA-PET imaging permits the follow-up of disease progression, the assessment of medical and surgical PD therapy strategies with possible neuroprotective properties and the detection of pre-clinical disease in subjects at risk for the disorder. The classical domain of morphological magnetic resonance imaging (MRI) is the differentiation of symptomatic Parkinsonism from PD. However, recent advances in MRI data acquisition and analysis techniques demonstrated MRI to be also a valuable tool for detection of nigral pathology in PD and for differentiation of neurodegenerative disorders with atypical Parkinsonism.     

Effects of ketamine/xylazine and isoflurane on rat brain glucose metabolism measured by 18F‐fluorodeoxyglucose‐positron emission tomography

The aim of the present study was to investigate changes in glucose metabolism in male Wistar rats induced by the anesthetics isoflurane and ketamine combined with xylazine via ¹⁸F‐fluorodeoxyglucose‐positron emission tomography. We analyzed the differential effects of the anesthetics on ¹⁸F‐fluorodeoxyglucose uptake and pharmacokinetics in 33 rats using quantification methods: (a) the standardized uptake value, (b) voxel‐based analyses, and (c) kinetic analysis. Both anesthetics reduced glucose uptake in the entire brain. The voxel‐based analyses detected smaller uptake reductions in the bilateral primary somatosensory system cortex and part of the limbic system in the ketamine‐xylazine (KX) group and in the vestibular nucleus in the isoflurane group. Through kinetic analysis, we found that the volume of distribution and the membrane transport rate K₁ were reduced in the KX group. Through various methods of ¹⁸F‐fluorodeoxyglucose‐positron emission tomography quantification, the present study found that anesthesia with the ketamine‐xylazine combination induced a global reduction of glucose metabolism compared with isoflurane; this reduction of metabolism was relatively lower in the primary somatosensory cortex and part of the limbic system. The volume of distribution of ¹⁸F‐fluorodeoxyglucose and its Glut1‐mediated transport across the brain membranes (K₁) were decreased in the KX group.     

Contralateral temporal hypometabolism on positron emission tomography in temporal lobe epilepsy

Introduction — No detailed case studies report lateralised hypometabolism on positron emission tomography (PET) contralateral to the epileptogenic focus in temporal lobe epilepsy (TLE). Material and methods — We performed ¹⁸F fluorodeoxyglucose (FDG) PET in two intractable TLE patients. Results — One had right temporal interictal spikes on electroencephalography (EEG) and a right medial temporal lobe lesion on magnetic resonance imaging (MRI). FDG-PET showed decreased uptake in the left temporal lobe. Right temporal ictal onset, with bilateral interictal epileptiform activity, occurred on intracranial EEG. He is seizure free after right temporal lobectomy and ganglioglioma resection. The second had right temporal lobe interictal and ictal EEG activity. MRI demonstrated right anteriomedial temporal increased T2 signal. Neuropsychology revealed bilateral cognitive dysfunction. FDG-PET showed left anterior temporal and lateral frontal hypometabolism. He is seizure free after right temporal lobectomy. Conclusion — These findings suggest that regional uptake asymmetry on FDG-PET may be give misleading lateralising information in TLE.     

Striatal dopamine metabolism in living monkeys examined by positron emission tomography

Positron emission tomography, using the dopa analogue [18F]6-fluoro-L-dopa, has been used to depict the neostriatum in living monkeys. The amount of 18F that accumulated preferentially in the striatum could be augmented by a peripheral decarboxylase inhibitor. Striatal 18F could also be discharged with reserpine. This is the first time that the regional distribution of a neurotransmitter has been demonstrated in monkeys.     

Quantitative imaging of neuroinflammation in human white matter: A positron emission tomography study with translocator protein 18 kDa radioligand, [18F]‐FEPPA

The ability to quantify translocator protein 18 kDa (TSPO) in white matter (WM) is important to understand the role of neuroinflammation in neurological disorders with WM involvement. This article aims to extend the utility of TSPO imaging in WM using a second‐generation radioligand, [¹⁸F]‐FEPPA, and high‐resolution research tomograph (HRRT) positron emission tomography (PET) camera system. Four WM regions of interests (WM‐ROI), relevant to the study of aging and neuroinflammatory diseases, were examined. The corpus callosum, cingulum bundle, superior longitudinal fasciculus, and posterior limb of internal capsule were delineated automatically onto subject's T₁‐weighted magnetic resonance image using a diffusion tensor imaging‐based WM template. The TSPO polymorphism (rs6971) stratified individuals to three genetic groups: high‐affinity binders (HAB), mixed‐affinity binders (MAB), and low‐affinity binders. [¹⁸F]‐FEPPA PET scans were acquired on 32 healthy subjects and analyzed using a full kinetic compartment analysis. The two‐tissue compartment model showed moderate identifiability (coefficient of variation 15–19%) for [¹⁸F]‐FEPPA total volume distribution (V_T) in WM‐ROIs. Noise affects V_T variability, although its effect on bias was small (6%). In a worst‐case scenario, ≤6% of simulated data did not fit reliably. A simulation of increased TSPO density exposed minimal effect on variability and identifiability of [¹⁸F]‐FEPPA V_T in WM‐ROIs. We found no association between age and [¹⁸F]‐FEPPA V_T in WM‐ROIs. The V_T values were 15% higher in HAB than in MAB, although the difference was not statistically significant. This study provides evidence for the utility and limitations of [¹⁸F]‐FEPPA PET to measure TSPO expression in WM. Synapse 68:536–547, 2014 . © 2014 Wiley Periodicals, Inc.     

Melanoma of the sellar region mimicking pituitary adenoma

We report here the case of an 82‐year‐old woman who presented with visual disturbance. MRI demonstrated a sellar mass. The diagnosis of pituitary adenoma was made. She underwent transnasal surgery. Histologic, immunohistochemical and ultrastructural studies indicated that the tumor was a melanoma. Despite an exhaustive search for a primary lesion elsewhere, none was found. The sellar tumor was considered a primary lesion, although extrasellar primary tumor imaging cannot be excluded with 100% certainty. Reported examples of melanoma affecting the sellar region are few. They exhibit morphologic features identical to those of melanomas arising elsewhere. Although very rare, primary melanomas enter into the differential diagnosis of sellar lesions.