Dept. of Neurology, Bangur Institute of Neurosciences, and Institute of Post Graduate Education & Research (IPGME&R), 52/1A, S.N. Pandit Street, Kolkata, 700 025, India.
Acta Neurol Belg. 2021 Aug;121(4):1009-1018. doi: 10.1007/s13760-020-01547-4. Epub 2020 Nov 23.
Posterior cortical atrophy (PCA) is a rare dementia affecting higher visual processing and other posterior cortical functions with atrophy and hypometabolism in occipito-parieto-temporal areas, more on right side. The objective of the study was to explore the clinical, neuropsychological, and radiological features of PCA patients and to compare them with typical multi-domain amnestic Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) patients. Four out of 9 patients of PCA fulfilling the criteria of Tang-Wai et al. (2004), 10 patients each of AD and aMCI fulfilling NIA-AA criteria were chosen. Patients were assessed clinically by experienced neurologists. Neuropsychological assessment was performed with standardized validated tests. Each patient underwent an MRI. FDG-PET was done for all PCA and six AD patients. PCA patients were younger, cognitively more impaired with rapid progression showing predominant visuospatial deficits consistent with the damage to the upstream of visual processing. AD patients presented predominantly with amnestic symptoms, with visuospatial dysfunction in some and aMCI had mild memory loss. Marked atrophy and hypometabolism in occipital, parietal and temporal areas in PCA, atrophy and hypometabolism in medial temporal areas in AD and minimal non-localized atrophy in MRI in aMCI were seen. Two PCA patients showed hypometabolism extending to the medial temporal and one to the frontal cortex. The clinical and imaging features of PCA are consistent with the damage predominantly to the upstream of visual processing. The difference between PCA and typical AD suggests involvement of AD pathology at different sites within a common disease-relevant network of brain regions.
后部皮质萎缩症（PCA）是一种罕见的痴呆症，影响高级视觉处理和其他后部皮质功能，其枕顶颞叶区域出现萎缩和代谢低下，右侧更为明显。本研究旨在探讨 PCA 患者的临床、神经心理学和影像学特征，并将其与典型的多领域遗忘型阿尔茨海默病（AD）和遗忘型轻度认知障碍（aMCI）患者进行比较。选择了符合 Tang-Wai 等人标准的 9 例 PCA 患者中的 4 例（2004 年）、10 例 AD 和 10 例 aMCI 患者。患者由经验丰富的神经科医生进行临床评估。神经心理学评估采用标准化的验证测试进行。每位患者均进行 MRI 检查。对所有 PCA 和 6 例 AD 患者进行 FDG-PET 检查。PCA 患者年龄较小，认知功能障碍更为严重，进展迅速，表现出主要的视觉空间缺陷，与视觉处理上游的损伤一致。AD 患者主要表现为遗忘症状，部分患者存在视觉空间功能障碍，而 aMCI 则有轻度记忆丧失。PCA 患者在枕叶、顶叶和颞叶区域有明显的萎缩和代谢低下，AD 患者在颞叶内侧区域有萎缩和代谢低下，而 aMCI 在 MRI 上有轻微的非局部性萎缩。两名 PCA 患者表现为代谢低下延伸至颞叶内侧，一名患者延伸至额叶。PCA 的临床和影像学特征与主要累及视觉处理上游的损伤一致。PCA 和典型 AD 之间的差异表明 AD 病理学在大脑区域的共同疾病相关网络中的不同部位参与。
