Oba Hiroshi, Tokumaru Aya
Department of Radiology, Teikyo University Hospital, 2-11-1 Kaga, Itabashi-ku, Tokyo 173-8606, Japan.
Brain Nerve. 2009 Nov;61(11):1269-73.
Frontotemporal lobar degeneration (FTLD) has been clinically categorized into 3 subtypes: frontotemporal dementia, semantic dementia, and progressive nonfluent aphasia. The histological subtypes of FTLD are Pick disease, corticobasal degeneration, dementia with grain, dementia with ubiquitin-positive tau-negative inclusions, and amyotrophic lateral sclerosis with dementia. In this paper, I briefly describe the magnetic resonance imaging (MRI) findings in Pick disease, progressive nonfluent aphasia, semantic dementia, and dementia with grain. In Pick disease, so-called knife-blade atrophy is seen in the frontal and temporal lobes at a relatively early stage of the disease. In progressive nonfluent aphasia atrophy is seen in the upper part of the left frontal lobe. Marked atrophy in the left temporal pole is observed in patients with semantic dementia, and asymmetrical atrophy around the ambient gyri is detected in patients who have dementia with grains. Although such focal atrophy can be observed on routine MRI, it is more easily detected on voxel-based morphometry and voxel-based specific regional analysis system for Alzheimer disease (VSRAD).
额颞叶变性（FTLD）在临床上已被分为3种亚型：额颞叶痴呆、语义性痴呆和进行性非流利性失语。FTLD的组织学亚型包括皮克病、皮质基底节变性、颗粒样痴呆、泛素阳性tau阴性包涵体痴呆以及伴有痴呆的肌萎缩侧索硬化。在本文中，我简要描述皮克病、进行性非流利性失语、语义性痴呆和颗粒样痴呆的磁共振成像（MRI）表现。在皮克病中，在疾病相对早期阶段，额叶和颞叶可见所谓的刀片样萎缩。在进行性非流利性失语中，左侧额叶上部可见萎缩。语义性痴呆患者左侧颞极有明显萎缩，颗粒样痴呆患者在环回周围检测到不对称萎缩。虽然在常规MRI上可观察到这种局灶性萎缩，但在基于体素的形态测量法和用于阿尔茨海默病的基于体素的特定区域分析系统（VSRAD）上更容易检测到。
