Migliaccio R, Agosta F, Rascovsky K, Karydas A, Bonasera S, Rabinovici G D, Miller B L, Gorno-Tempini M L
Memory and Aging Center, Department of Neurology, University of California, San Francisco, CA 94143-1207, USA.
Neurology. 2009 Nov 10;73(19):1571-8. doi: 10.1212/WNL.0b013e3181c0d427.
Posterior cortical atrophy (PCA) and logopenic progressive aphasia (LPA) are clinical syndromes associated with posterior brain atrophy. We compared PCA and LPA to each other and to an age-matched group of patients with early age at onset of Alzheimer disease (EO-AD). We hypothesized that these 3 syndromes are part of a single clinical and biologic continuum.
Voxel-based morphometry (VBM) was used to assess atrophy in 14 PCA, 10 LPA, and 16 EO-AD patients compared to 65 healthy controls. Genetic analysis for APOE was conducted in 30 patients and 44 controls. Four patients came to autopsy. An additional 14 were studied with the beta-amyloid specific PET with tracer (11)C-labeled Pittsburgh Compound-B (PIB).
VBM results demonstrated that, compared to controls, each patient group showed a large area of overlapping atrophy in bilateral parietal, occipital, precuneus, posterior cingulate, posterior temporal, and hippocampal regions. Surrounding this common area, group-specific atrophy was found in small, symptom-specific regions for each group: the right ventral-occipital and superior parietal regions in PCA, the left middle and superior temporal gyri in LPA, and the prefrontal cortex in EO-AD. APOE epsilon4 frequency was higher in all patient groups compared to controls. Four PCA, 5 LPA, and 8 EO-AD patients showed evidence of cortical amyloid at pathology (n = 3) or on PIB-PET (n = 14).
Logopenic progressive aphasia and posterior cortical atrophy showed largely overlapping anatomic and biologic features with early age at onset of Alzheimer disease, suggesting that these clinical syndromes represent the spectrum of clinical manifestation of the nontypical form of Alzheimer disease that presents at an early age.
后皮质萎缩（PCA）和语义性进行性失语（LPA）是与后脑萎缩相关的临床综合征。我们将PCA和LPA相互比较，并与年龄匹配的早发型阿尔茨海默病（EO-AD）患者组进行比较。我们假设这三种综合征是单一临床和生物学连续体的一部分。
采用基于体素的形态学测量（VBM）评估14例PCA患者、10例LPA患者和16例EO-AD患者的萎缩情况，并与65名健康对照者进行比较。对30例患者和44名对照者进行了APOE基因分析。4例患者进行了尸检。另外14例患者接受了用示踪剂（11）C标记的匹兹堡化合物B（PIB）进行的β淀粉样蛋白特异性PET研究。
VBM结果显示，与对照组相比，每个患者组在双侧顶叶、枕叶、楔前叶、后扣带回、颞叶后部和海马区均显示出大面积的重叠萎缩。在这个共同区域周围，在每个组的小的、症状特异性区域发现了组特异性萎缩：PCA患者的右侧枕腹侧和顶上叶区域，LPA患者的左侧颞中回和颞上回，以及EO-AD患者的前额叶皮质。与对照组相比，所有患者组的APOE ε4频率均较高。4例PCA患者、5例LPA患者和8例EO-AD患者在病理学（n = 3）或PIB-PET（n = 14）上显示出皮质淀粉样蛋白的证据。
语义性进行性失语和后皮质萎缩在很大程度上与早发型阿尔茨海默病具有重叠的解剖和生物学特征，表明这些临床综合征代表了早发型非典型阿尔茨海默病的临床表现谱。
