目的:研究n 11C-匹兹堡化合物B (PIB)在轻度认知障碍(MCI)与阿尔茨海默病(AD)患者诊断中的应用价值及可能影响n 11C-PIB结合的因素。n 方法:回顾性分析2017年1月至2019年12月期间在陆军军医大学大坪医院行n 11C-PIB PET显像的6例认知功能正常患者(NC)[男、女各3例，年龄(64.5±12.3)岁]、11例MCI患者[男4例，女7例，年龄(64.5±9.8)岁]和21例AD患者[男7例，女14例，年龄(68.1±9.1)岁]对n 11C-PIB的摄取情况，采用标准摄取值比值(SUVR)法及视觉分析评估n 11C-PIB在患者脑皮质的分布区域和结合量，并收集患者相关临床资料[包括年龄、性别、文化程度、认知障碍程度、神经心理学量表评分、血管危险因素(VRF)、载脂蛋白E(ApoE)基因等]。采用单因素方差分析或Fisher确切概率法进行组间比较，两两比较采用最小显著差异n t检验，采用多元线性回归分析可能影响n 11C-PIB结合的因素。n 结果:NC、MCI及AD组各脑叶组间比较SUVR差异均有统计学意义(3组各脑叶SUVR均值范围：1.16～1.26、1.19～1.35和1.40～1.61；n F值：5.331～9.279，均n P<0.05)。NC组与PIB阳性的MCI患者比较，后扣带回及楔前叶SUVR差异均有统计学意义(1.20±0.15与1.50±0.12, 1.18±0.15与1.59±0.13；n F值：6.389和10.668，n t值：-2.33和-3.10,均n P0.05)。视觉分析结果显示，AD组额叶[85.7%(18/21)]、后扣带回[85.7%(18/21)]、楔前叶[81.0%(17/21)]、颞叶[81.0%(17/21)]和枕叶[47.6%(10/21)]PIB阳性率明显高于MCI组(4/11、4/11、4/11、3/11和1/11；均n P<0.05)。多元线性回归分析示认知障碍程度是影响各脑叶SUVR的独立危险因素(n b值：0.377～0.536，均n P<0.05)，携带ApoE ε4基因是影响楔前叶SUVR的独立危险因素(n b＝0.290，n P<0.05)。n 结论:11C-PIB有助于临床对MCI及AD患者的诊断；认知障碍程度及ApoE ε4基因携带是影响n 11C-PIB结合的独立危险因素。n “,”Objective:To investigate the diagnostic value of n 11C-Pittsburgh compound B (PIB) in patients with mild cognitive impairment (MCI) and Alzheimer′s disease (AD) and explore the factors that may affect the binding of n 11C-PIB.n Methods:From January 2017 to December 2019, the n 11C-PIB uptake of 6 patients with normal cognitive (NC; 3 males, 3 females, age: (64.5±12.3) years), 11 patients with MCI (4 males, 7 females, age: (64.5±9.8) years) and 21 patients with AD (7 males, 14 females, age: (68.1±9.1) years) from Daping Hospital, Army Medical University were retrospectively analyzed. Regional n 11C-PIB binding was assessed by using standardized uptake value ratio (SUVR) and visual reading of n 11C-PIB scan. Clinical data, including age, gender, education level, cognitive impairment, neuropsychological scale score, vascular risk factors (VRF), apolipoprotein E (ApoE) gene, were collected and differences among groups were analyzed by using one-way analysis of variance, least significant difference n t test or Fisher exact test. Factors that affected the n 11C-PIB binding were analyzed by multiple linear regression.n Results:SUVR of cerebral lobe among NC, MCI and AD groups were significantly different (range of mean SUVR: 1.16-1.26, 1.19-1.35 and 1.40-1.61; n F values: 5.331-9.279, all n P<0.05). For positive PIB patients, SUVR of posterior cingulate and precuneus were increased in MCI group compared with NC group (1.20±0.15n vs 1.50±0.12, 1.18±0.15 n vs 1.59±0.13; n F values: 6.389 and 10.668, n t values: -2.33 and -3.10, both n P0.05). Visual analysis showed that the positive rates of PIB in frontal lobe (85.7%(18/21)), posterior cingulate (85.7%(18/21)), precuneus (81.0%(17/21)), temporal lobe (81.0%(17/21)) and occipital lobe (47.6%(10/21)) in AD were higher than those in MCI (4/11, 4/11, 4/11, 3/11 and 1/11, respectively; alln P<0.05). Multiple linear regression showed that the degree of cognitive impairment were independent risk factors for SUVR of all lobes (n b values: 0.377-0.536, all n P<0.05). The ApoE ε4 gene was independent risk factor for SUVR of precuneus (n b=0.290, n P<0.05).n Conclusion:11C-PIB is helpful for clinical diagnosis of MCI and AD patients and the degree of cognitive impairment and ApoE ε4 gene may be independent risk factors for increasing n 11C-PIB binding.n