Meijboom Rozanna, Steketee Rebecca M E, Jiskoot Lize C, Bron Esther E, van der Lugt Aad, van Swieten John C, Smits Marion
Department of Radiology and Nuclear Medicine, Erasmus MC-University Medical Center Rotterdam, Rotterdam, Netherlands.
Center for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom.
Front Neurol. 2019 Nov 14;10:1207. doi: 10.3389/fneur.2019.01207. eCollection 2019.
Phenocopy frontotemporal dementia (phFTD) shares core characteristics with behavioral variant frontotemporal dementia (bvFTD), yet without associated cognitive deficits and brain abnormalities on conventional magnetic resonance imaging (MRI), and without progression. Using advanced MRI techniques, we previously observed subtle structural and functional brain changes in phFTD similar to bvFTD. The aim of the current study was to follow these as well as cognition in phFTD over time, by means of a descriptive case series. Cognition, gray matter (GM) volume and white matter (WM) microstructure, and perfusion of 6 phFTD patients were qualitatively compared longitudinally (3-years follow-up), and cross-sectionally with baseline data from 9 bvFTD patients and 17 controls. For functional brain changes, arterial spin labeling (ASL) was performed to assess GM perfusion. For structural brain changes, diffusion tensor imaging was performed to assess WM microstructure and T1w imaging to assess GM volume. MRI acquisition was performed at 3T (General Electric, US). Clinical profiles of phFTD cases at follow-up are described. At follow-up phFTD patients showed clinical symptomatology similar to bvFTD, but had a relatively stable clinical profile. Longitudinal qualitative comparisons in phFTD showed some deterioration of language and memory function, a stable pattern of structural brain abnormalities and increased perfusion over time. Additionally, both baseline and follow-up cognitive scores and structural values in phFTD were generally in between those of controls and bvFTD. Although a descriptive case series does not allow for strong conclusions, these observations in a unique longitudinal phFTD patient cohort are suggestive of the notion that phFTD and bvFTD may belong to the same disease spectrum. They may also provide a basis for further longitudinal studies in phFTD, specifically exploring the structural vs. functional brain changes. Such studies are essential for improved insight, accurate diagnosis, and appropriate treatment of phFTD.
表型模仿性额颞叶痴呆（phFTD）与行为变异型额颞叶痴呆（bvFTD）具有核心特征，但在传统磁共振成像（MRI）上无相关认知缺陷和脑异常，且无病情进展。利用先进的MRI技术，我们之前观察到phFTD患者存在与bvFTD相似的细微脑结构和功能变化。本研究的目的是通过描述性病例系列，对phFTD患者的这些变化以及认知情况进行长期随访。对6例phFTD患者的认知、灰质（GM）体积、白质（WM）微观结构和灌注情况进行纵向（3年随访）定性比较，并与9例bvFTD患者和17例对照的基线数据进行横断面比较。对于脑功能变化，采用动脉自旋标记（ASL）评估GM灌注。对于脑结构变化，采用扩散张量成像评估WM微观结构，采用T1加权成像评估GM体积。MRI扫描在3T（美国通用电气公司）设备上进行。描述了随访时phFTD病例的临床特征。随访时，phFTD患者表现出与bvFTD相似的临床症状，但临床特征相对稳定。phFTD患者的纵向定性比较显示，语言和记忆功能有一定程度的恶化，脑结构异常模式稳定，灌注随时间增加。此外，phFTD患者的基线和随访认知评分及结构值通常介于对照组和bvFTD患者之间。虽然描述性病例系列无法得出强有力的结论，但在独特的phFTD患者纵向队列中的这些观察结果提示，phFTD和bvFTD可能属于同一疾病谱。它们也可能为phFTD的进一步纵向研究提供基础，特别是探索脑结构与功能变化。此类研究对于深入了解、准确诊断和恰当治疗phFTD至关重要。
