Neurobehavior Unit, West Los Angeles VA Healthcare Center, CA 90073, USA.
Am J Alzheimers Dis Other Demen. 2011 Aug;26(5):413-8. doi: 10.1177/1533317511418955. Epub 2011 Aug 9.
Posterior cortical atrophy (PCA) may represent a discrete syndrome of Alzheimer's disease (AD) rather than amnestic AD with visual deficits.
We separated 30 patients with PCA based on ventral and dorsal visual symptoms using cluster analysis and analyzed the demographic, cognitive, and functional imaging features.
This analysis revealed subgroups of 26 dorsal and 4 ventral patients. The ventral subgroup had greater confrontational naming impairment, and the dorsal subgroup had greater hypofunction in the parietal regions. The PCA cohort had memory retrieval rather than encoding deficits, and clinical follow-up showed relative isolation of dorsal and ventral visual manifestations.
These results support 2, mostly nonoverlapping syndromes in patients with PCA, with the commonest affecting the dorsal visual pathway; moreover, the memory retrieval difficulty in the patients with PCA was dissimilar to the amnestic pattern in typical AD. These results suggest that, in most cases, PCA syndromes are discrete clinical variants of AD.
后部皮质萎缩（PCA）可能代表阿尔茨海默病（AD）的一种独特综合征，而不是伴有视觉缺陷的遗忘型 AD。
我们使用聚类分析根据腹侧和背侧视觉症状将 30 例 PCA 患者分开，并分析了人口统计学、认知和功能影像学特征。
该分析揭示了 26 例背侧和 4 例腹侧患者亚组。腹侧亚组存在更大的对视命名障碍，而背侧亚组在顶叶区域的功能低下更明显。PCA 患者群存在记忆提取而非编码缺陷，临床随访显示背侧和腹侧视觉表现相对孤立。
这些结果支持 PCA 患者存在 2 种、大多数不重叠的综合征，最常见的影响背侧视觉通路；此外，PCA 患者的记忆提取困难与典型 AD 的遗忘模式不同。这些结果表明，在大多数情况下，PCA 综合征是 AD 的离散临床变异型。
