Abstract: Objective  To delineate the cerebral metabolic patterns presented in ¹⁸F-FDG PET images in various types of dementia with SPM analysis.  Methods  Patients who underwent ¹⁸F-FDG PET scanning with a retrospectively confirmed diagnosis according to strictly defined clinical research criteria were studied. Clinical follow-up enabled appropriate patient inclusion. A total of 62 patients were included, of which 20 patients were diagnosed as Alzheimer's disease (AD), 20 frontotemporal dementia (FTD), 10 dementia with Lewy body (DLB), 7 progressive supranuclear palsy (PSP), 3 primary progressive aphasia (PPA), 1 corticobasal ganglionic degeneration (CBD), 1 multiple system atrophy (MSA). ¹⁸F-FDG PET images of each group were analyzed and compared to 20 healthy controls using SPM5. Results  Disease-specific patterns of relatively decreased metabolic activity were found in AD (bilateral parietotemporal regions and frontal regions sparing sensorimotor cortex), FTD (asymmetric frontotemporal regions), DLB (occipital lobe, visual cortex and bilateral superior temporal gyrus), PSP (bilateral dorsolateral prefrontal cortex, anterolateral temporal regions, caudate nucleus and mesencephalon), PPA (Broca's area in left frontal lobe, left temporal cortex excepting posterior superior temporal gyrus, CBD (asymmetricly involved cortical regions, prodominately on right side, around bilateral central sulcus and right basal ganglia), MSA (bilateral cerebellum dorsolateral cortex and left putamen), and right medial temporal cortex).  Conclusions  Specific dementia related cerebral metabolic patterns in ¹⁸F-FDG PET might assist in early differential diagnosis of neurodegenerative diseases.

Key words: Dementia, Positron-emission tomography

摘要： 目的 探讨不同类型痴呆患者基于像素水平的脑代谢图型特点。方法 对最终临床诊断为阿尔茨海默病（20 例）、额颞叶痴呆（20 例）、路易体痴呆（10 例）、进行性核上性麻痹（7 例）、原发性进行性失语（3 例）、皮质基底节变性（1 例）和多系统萎缩（1 例）等认知功能障碍患者的¹⁸F-FDG PET 显像资料进行回顾分析，描述各种神经变性疾病脑代谢降低区域和程度。结果 SPM 分析表明，各种神经变性疾病引起的痴呆¹⁸F-FDG PET 显像均表现为皮质代谢降低，但其代谢图型变化明显不同：阿尔茨海默病组以双侧颞顶叶和额叶皮质代谢降低为主，基本感觉运动皮质、枕叶、基底节和丘脑活性保留；额颞叶痴呆组额叶和颞叶皮质不对称性代谢降低，伴部分顶叶皮质和基底节、丘脑等皮质下核团不同程度代谢降低；路易体痴呆组枕叶、视皮质和双侧颞上回前部代谢降低；进行性核上性麻痹组双侧前额叶背外侧、颞叶前外侧、中脑和双侧尾状核代谢降低；原发性进行性失语组左侧额叶Broca 区、左侧颞叶皮质（除左侧颞上回后部）和右侧颞叶内侧皮质代谢降低；皮质基底节变性组双侧中央沟周围额顶叶皮质（右侧显著）、右侧基底节代谢降低；多系统萎缩组双侧小脑背外侧皮质和左侧壳核代谢降低。结论 神经变性疾病所致痴呆在¹⁸F-FDG PET 显像中表现出各自特征性脑代谢降低图型，¹⁸F-FDG PET 显像有可能成为痴呆鉴别诊断的一种辅助手段。

关键词: 痴呆, 正电子发射断层显像术