Oghabian Mohammad Ali, Batouli Seyed Amir Hossein, Norouzian Maryam, Ziaei Maryam, Sikaroodi Hajir
Medical Physics and Biomedical Engineering Department, Tehran University of Medical Sciences, Tehran, Iran.
J Res Med Sci. 2010 Mar;15(2):84-93.
Alzheimer's disease is the most common form of dementia which is still difficult to be differentiated from other types of brain disorders. Moreover, Mild Cognitive Impairment refers to the presence of cognitive impairments that is not severe enough to meet the criteria of Alzheimer's, and its diagnosis in early stages is so critical. There is currently no distinct method available for diagnosing Alzheimer's or Mild Cognitive Impairment, and their diagnosis needs a combination of different methods and assessments.
The aim of this study was to evaluate the effectiveness of functional Magnetic Resonance Imaging (fMRI) in differentiating between Alzheimer's, Mild Cognitive Impairment (MCI) and healthy aging. To prove fMRI's ability, resting-state brain activation patterns between these three groups of subjects were compared using Independent Component Analysis (ICA) algorithm. Forty age- and sex-matched subjects, 15 elderly, 11 MCI and 14 Alzheimer's subjects were examined.
The results showed that during a certain resting-state session, healthy aging brain benefits from larger area and greater intensity of activation (compared with MCI and Alzheimer's group) in Posterior Cingulate Cortex (PCC) region of the brain, as part of Default Mode Network.
This difference in activation pattern can be used as a diagnostic criterion in using fMRI for differentiating between Alzheimer's Disease (AD), MCI and healthy aging.
阿尔茨海默病是最常见的痴呆形式,目前仍难以与其他类型的脑部疾病相区分。此外,轻度认知障碍是指存在认知障碍,但严重程度不足以达到阿尔茨海默病的标准,其早期诊断至关重要。目前尚无明确的方法可用于诊断阿尔茨海默病或轻度认知障碍,其诊断需要结合不同的方法和评估。
本研究的目的是评估功能磁共振成像(fMRI)在区分阿尔茨海默病、轻度认知障碍(MCI)和健康衰老方面的有效性。为证明fMRI的能力,使用独立成分分析(ICA)算法比较了这三组受试者的静息态脑激活模式。对40名年龄和性别匹配的受试者进行了检查,其中15名老年人、11名MCI患者和14名阿尔茨海默病患者。
结果表明,在特定的静息态期间,作为默认模式网络的一部分,健康衰老的大脑在大脑后扣带回皮质(PCC)区域的激活面积更大、强度更高(与MCI和阿尔茨海默病组相比)。
这种激活模式的差异可作为使用fMRI区分阿尔茨海默病(AD)、MCI和健康衰老的诊断标准。