PET/CT显像在阿尔茨海默病早期诊断中的应用

阿尔茨海默病（AD）是老年人常见的神经系统变性疾病，是痴呆最常见的病因，早期诊断困难。PET显像对本病的早期诊断有重要价值。目前淀粉样蛋白显像是早期诊断AD的最佳选择，葡萄糖显像对病情评估有较高价值。本文对PET显像中葡萄糖显像、淀粉样蛋白显像和tau蛋白显像在AD早期诊断中的应用及进展进行综述。     

正电子发射断层显像诊断阿尔茨海默病的Meta分析

目的 系统评价正电子发射断层显像(PET)氟脱氧葡萄糖(FDG)、神经元外β-淀粉样蛋白(Aβ)、tau蛋白诊断阿尔茨海默病(AD)的应用价值.方法 计算机检索PubMed、EMbase、The Cochrane Library、CNKI、WanFang Data、VIP和CBM数据库,搜集有关PET对AD诊断价值的研...     

多模态影像技术在阿尔茨海默病早期诊断中的应用价值

阿尔茨海默病(Alzheimer’s disease, AD)是以进行性认知功能障碍和记忆损害为特征的神经系统退行性疾病,也是我国人口老龄化进程中面临的巨大挑战。在AD早期阶段进行干预对延缓病情进展以及改善预后具有重要意义,因此,AD的早期诊断至关重要。多模态影像技术从结构、功能、代谢等方面为AD的发病机制和早期临床诊断提供重要的影像学证据。本文对多模态影像技术,包括结构、功能等MRI和正电子发射计算机断层显像(positron emission computed tomography, PET)技术进行综述,通过反映不同脑部特征对AD患者进行早期诊断方面的应用价值进行分析,以期从影像视角揭示AD早期病理改变,提高AD早期诊断效能,未来指导临床治疗。     

PET／CT显像剂在脑胶质瘤中的应用研究进展

神经胶质瘤简称胶质瘤,是人类中枢神经系统最常见的恶性肿瘤,约占颅内肿瘤的40％-50％。传统的CT、MRI影像学检查手段都是解剖学显像方法,虽然其强化原理基本相似,但均不能反映肿瘤的细胞代谢水平。近年来随着正电子放射性药物和PEr、PET／CT技术的发展,使得肿瘤研究发展到活体病理和生化改变的分子影像阶段。PET／CT在脑胶质瘤诊断中的应用价值日益受到重视。     

多种正电子示踪剂PET联合显像在肿瘤基础研究、临床诊断和疗效监测中的应用进展

正电子示踪剂PET显像是反映生理和病理状态下在分子水平监测人体组织细胞代谢、酶和受体活性以及基因表达的重要的分子影像技术,PET/CT也是迄今用于临床分子影像成像的最佳设备.PET/CT显像在临床主要用于肿瘤、脑和心血管疾病的早期诊断,疗效监测和对治疗方案的选掸提供参考依据.     

肺癌PET分子显像应用进展

肺癌是人类最常见的恶性肿瘤之一.近年来,其发病率与死亡率明显增高,占所有恶性肿瘤的第一位.早期诊断、正确有效的治疗对提高患者预后及生存率至关重要.随着分子影像学的发展,大大提高了对疾病的诊断能力.PET作为目前最具活力的分子显像技术,已应用于多种疾病的诊断,尤其是恶性肿瘤的诊断.本文综述了以PET/PET-CT为代表的分子显像在肺癌中的应用进展.     

PET在癫痫定位诊断中的应用

目的：更深入的了解PET在癫痫定位诊断中的作用。方法：复习国内外近年来相关研究结果及文献。结果：PET足一种非侵入性的影像学俭查方法,包括代谢显像和神经受体显像等,在癫痫定位诊断中具有较高的特异性和准确度,不仅能发现形态结构异常还能发现功能异常的病灶：结论：PET显像在癫痫定位诊断中具有重要的意义。     

CT、MRI及与PET融合显像评价宫颈癌分期及淋巴结转移中的应用进展

传统影像学检查方法(CT、MRI)在宫颈癌分期及淋巴结转移的诊断方面应用较为广泛,对制定治疗方案、改善预后和降低死亡率有重要的作用。近年来,随着分子影像技术的发展,多模态分子影像技术(PET/CT及PET/MR)被逐渐应用于宫颈癌的诊断并指导治疗。本文对CT、MRI及与PET融合显像技术在宫颈癌分期及淋巴结转移评价中的临床应用进行综述。     

18F-FDG PET脑显像和多巴胺能神经元突触功能PET脑显像研究帕金森病进展

帕金森病（PD）是常见神经退行性疾病，PET对早期鉴别、诊断和评价PD具有特别优势，主要示踪剂为反映葡萄糖代谢的¹⁸F-FDG和反映纹状体多巴胺能神经元突触功能的靶向示踪剂。本文就¹⁸F-FDG PET脑显像和多巴胺能神经元突触功能PET脑显像应用于PD研究现状和进展进行综述。     

多模态影像学研究帕金森病伴左旋多巴诱导异动症进展

帕金森病(PD)是常见神经退行性疾病;左旋多巴诱导异动症(LID)是PD患者长期服用左旋多巴药物所致常见致残性运动并发症。MR结构成像、功能MRI及PET显像可观察LID患者脑结构、功能及代谢改变,为阐述脑相关发病机制提供多模态影像学依据,有助于临床早期诊断。本文就多模态影像学研究PD伴LID进展进行综述。     

Exploring a Mathematical Model for the Kinetics of β-Amyloid Molecular Imaging Probes through a Critical Analysis of Plaque Pathology

Amyloid plaques are highly heterogeneous in content, size, density, and macromolecular crowding, as they are composed of masses of fibrils and other cellular material. Given this target architecture, the aggregated microenvironment offers a unique imaging target for ligands and positron emission tomography (PET) molecular imaging probes (MIPs). In this work, we address how the heterogeneous microenvironment of a plaque and its evolution may affect the kinetic rate constant of PET MIPs. We argue that macromolecular crowding will result in anomalous diffusion within plaque regions. To account for anomalous diffusion within plaques, we propose a diffusion-limited ligand-receptor compartmental model. Given the current state of knowledge about the pathological progression of Alzheimer's disease (AD), the model's parameters may be a function of the pathological progression of AD, which could result in biased estimates of the true amyloid load. The bias may be partially overcome through evaluation in conjunction with other measures of AD progression including cerebral glucose metabolism rate, neuronal cell loss, and activated inflammatory presence.     

阿尔茨海默病及轻度认知损伤患者PET与MRI分析

目的 探讨PET葡萄糖代谢成像与MR结构成像诊断阿尔茨海默病（AD）与轻度认知损伤（MCI）的临床价值。方法 收集AD患者18例（AD组）、MCI患者6例（MCI组）,其中AD患者包括11例中重度AD） 中重度AD组）及7例轻度AD） 轻度AD组）,另招募10名健康志愿者（对照组）,同期进行PET与MR结构成像,通过视觉评价与定量分析法观察脑内放射性分布及海马萎缩情况。结果 所有AD患者（18/18,100%）均可见脑内特定区域葡萄糖代谢减低,其中11例中重度AD患者均同时伴有海马萎缩,7例轻度AD患者中3例可见海马萎缩;MCI患者中,5例（5/6,83.33%）未见海马萎缩,但其中2例可见葡萄糖代谢减低。对照组（10/10,100%）均未见海马萎缩,其中2例可见轻度脑萎缩,FDG分布对称性轻度减低。结论 PET及MRI均可用于诊断AD与MCI,但各有侧重,二者联合应用有利于进一步提高对AD的诊断能力。     

Resting state FDG-PET functional connectivity as an early biomarker of Alzheimer's disease using conjoint univariate and independent component analyses

Imaging cerebral glucose metabolism with positron emission tomography (PET) in Alzheimer's disease (AD) has allowed for improved characterisation of this pathology. Such patterns are typically analysed using either univariate or multivariate statistical techniques. In this work we combined voxel-based group analysis and independent component analysis to extract differential characteristic patterns from PET data of glucose metabolism in a large cohort of normal elderly controls and patients with AD. The patterns were used in conjunction with a support vector machine to discriminate between subjects with mild cognitive impairment (MCI) at risk or not of converting to AD. The method was applied to baseline fluoro-deoxyglucose (FDG)-PET images of subjects from the ADNI database. Our approach achieved improved early detection and differentiation of typical versus pathological metabolic patterns in the MCI population, reaching 80% accuracy (85% sensitivity and 75% specificity) when using selected regions. The method has the potential to assist in the advance diagnosis of Alzheimer's disease, and to identify early in the development of the disease those individuals at high risk of rapid cognitive decline who could be candidates for new therapeutic approaches.     

Alzheimer' s disease

Progressive accumulation of amyloid plaques in the brain is a characteristic pathological change in Alzheimer's disease (AD) and precedes the presentation of cognitive impairment. In vivo detection of amyloid deposits using molecular imaging technique would thus prove useful for early diagnosis of AD and tracking disease progression. Several imaging agents have been developed that can noninvasively detect amyloid plaques in the brain and successfully differentiated AD patients from healthy normal individuals using positron emission tomography. Although validation remains required as to whether retention of these agents in the neocortex truly reflects the level of amyloid deposition, such findings suggest the potential usefulness of amyloid imaging technique for early diagnosis of AD.     

The Application of Positron-Emitting Molecular Imaging Tracers in Alzheimer’s Disease

The symptomatology and known pathology of Alzheimer's disease are restricted to the central nervous system. This review details studies of PET tracers aimed at interrogating cholinergic, serotonergic, opiate, benzodiazepine, and inflammatory pathways as well as PET tracers that illuminate amyloid plaques and neurofibrillary tangles in AD. Progress has been remarkable. Together with studies of brain structure with MRI and of functional regional brain activity, e.g., through measures of blood flow and glucose metabolic rate, molecular imaging promises to dramatically alter our understanding of the structural and physiological abnormalities underlying AD symptomatology. A more immediate impact on the diagnosis and treatment evaluation of AD patients in clinical trials is predicted while the possibility of personalized treatment or prevention of AD may not be that far away.     

Neuroimaging of Alzheimer disease: current role and future potential

Alzheimer disease (AD), the most common cause of dementia in the elderly, is a progressive neurodegenerative disorder, associated with deterioration in cognition and behaviour. With the availability of newer drugs for symptoms treatments there is a general agreement to the need of an early diagnosis and an the development of new sensitive tools, to identify and/or monitor early cerebral changes, suggestive for AD. CT and MRI are recommended for routine evaluation, in order to exclude treatable causes of dementia and to exactly evaluate the degree of cerebral atrophy and the presence of parenchymal signal abnormalities. Functional imaging, including PET, SPECT and functional MR techniques, are able to investigate physiological cerebral function, such as blood perfusion, metabolism, activation, molecular composition and water diffusibility, and have the potential to detect subtle pathological changes earlier during course of disease. MRI can provide both an accurate morphological assessment and a functional evaluation. Further investigations are needed to precisely define which will be the role of the different MR techniques. Most likely an exhaustive evaluation of AD will include information obtained by conventional and functional imaging, combined with clinical, laboratory and genetic findings.     

Neuroimaging in dementia: in vivo amyloid imaging

Dementia, a progressive cognitive decline, leads to a gradually increasing restriction of daily activities. Alzheimer's disease (AD) is the most common form of dementia. The pathological features of AD include plaques and tangles which are constituted by amyloid beta peptide (A beta) and tau protein. These amyloidogenic molecules have been mechanistically implicated in the pathogenesis of AD and related neurodegenerative dementias. The key strategy for establishment of diagnostic and therapeutic approaches to AD is sensitive and specific detection of the incipient neuropathology characteristics of AD, combined with emerging treatments that counteract molecular processes in AD pathogenesis. Recent advances in molecular imaging research have enabled visualization of brain amyloidosis. The rapid development of different compounds suitable for visualizing amyloid would permit pathology-specific diagnosis of AD at an asymptomatic stage in a noninvasive manner, and could also allow early immunotherapeutic intervention without causing an excessive neuroinflammatory response.     

统计参数图在Alzheimer病PET成像中的应用

目的：研究统计参数图(SPM)分析方法在Alzheimer病(AD)PET成像中的作用。方法：利用^18F-FDG PET成像方法分别对11例AD及12例对照者进行PET脑显像，采用SPM方法进行分析，总结AD的成像特点。结果：SPM分析方法显示，AD患者两侧大脑皮层顶叶、颞叶、额叶及后扣带回等部位葡萄糖代谢明显降低，左、右不对称。而两侧皮层下基底节区等结构代谢不受影响。结论：SPM方法能够客观准确显示出AD患者脑代谢降低部位，为康复治疗的脑功能研究提供一种实用的工具。