Hess Christopher P
Department of Radiology and Biomedical Imaging, University of California, San Francisco, 505 Parnassus Avenue, Room L-358, San Francisco, CA 94143-0628, USA.
Magn Reson Imaging Clin N Am. 2009 May;17(2):215-24. doi: 10.1016/j.mric.2009.02.003.
With estimates of more than 5 million people with Alzheimer's disease (AD) now living in the United States and an increasing prevalence of the disease among the aging population, there is an urgent need for the development of reliable biomarkers for early diagnosis and evaluation of potential therapeutic interventions. Structural MR imaging, the focus of the most intense research in this area to date, has identified characteristic patterns of macroscopic atrophy within larger groups of patients who have clinically probable AD, particularly within the medial temporal lobes. These changes are thought to reflect underlying neuronal cell death, and as a result are consistently demonstrated only in the late stages of the disease. Paralleling the development of new molecular markers for AD pathology in nuclear medicine are a number of encouraging results in the application of functional, perfusion, and diffusion imaging which point to a growing role for MR imaging in the evaluation of AD. This article surveys current research on the use of diffusion MR imaging for the evaluation of patients who have mild cognitive impairment and AD, and summarizes the important unifying results that are beginning to emerge on the potential role for diffusion imaging in practice.
据估计，目前美国有超过500万人患有阿尔茨海默病（AD），且该疾病在老年人群中的患病率不断上升，因此迫切需要开发可靠的生物标志物，用于早期诊断和评估潜在的治疗干预措施。结构磁共振成像（MR成像）是迄今为止该领域研究最为密集的重点，已在临床上可能患有AD的较大患者群体中识别出宏观萎缩的特征模式，尤其是在内侧颞叶。这些变化被认为反映了潜在的神经元细胞死亡，因此仅在疾病晚期才能持续显现。与核医学中AD病理学新分子标记物的发展相平行的是，功能、灌注和扩散成像的应用取得了一些令人鼓舞的成果，这表明MR成像在AD评估中的作用日益增强。本文综述了目前关于使用扩散MR成像评估轻度认知障碍和AD患者的研究，并总结了扩散成像在实际应用中的潜在作用开始显现的重要统一结果。
