Please use this identifier to cite or link to this item:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/50817
Title: | 自發生理活動對描述阿茲海默症患者靜息態功能性核磁共振影像之影響 Effect of Spontaneous Physiology on Characterizing the Resting-State Functional Magnetic Resonance Imaging of Alzheimer’s Disease Patients |
Authors: | Yi-Tien Li 李宜恬 |
Advisor: | 林發暄(Fa-Hsuan Lin) |
Keyword: | 阿茲海默症,靜息態,默認網路模式,生理雜訊,RETROICOR,RVHRCOR,功能性核磁共振影像,老化, Alzheimer’s disease,resting-state,default mode network,physiological noise,RETROICOR,RVHRCOR,fMRI,aging, |
Publication Year : | 2016 |
Degree: | 碩士 |
Abstract: | 先前有許多研究指出阿茲海默症患者 (Alzheimer’s disease, AD) 相較於正常人具有不同默認網路模式 (Default mode network, DMN) 的特徵。然而,這些研究卻鮮少考慮了生理雜訊影響的因素。因此,本實驗將針對自發性生理活動對於描述阿茲海默症患者之默認網路模式的影響進行研究,其目的在於檢驗當由自發性心跳以及呼吸所造成的生理雜訊從靜息態功能性核磁共振影像 (functional magnetic resonance imaging, fMRI) 中去除後,其默認網路模式的特徵將會造成多少的改變。
靜息態功能性磁振造影經由T2*加權之平面回波成像 (Echo planer imaging, EPI) 擷取400秒的影像。心跳及呼吸的信號將分別由脈波血氧儀以及呼吸帶監測以及紀錄。我們利用RETROICOR (Gary H. Glover, 2000) 的方式去除與相位相關的生理假影。其餘相較低頻率之生理影響,例如:相同相位卻不同振幅之呼吸變異以及相同相位卻不同時間間隔的心跳速率變異,將由RVHRCOR (Chang and Glover, 2009) 的方式做校正。 校正生理訊號以前,阿茲海默症患者與正常對照組相比具有不同的默認網路模式之特徵,然而,這個差異在生理訊號影響被去除後將不能再被顯著地觀察到。此外,我們也發現阿茲海默症患者與正常對照組在由呼吸體積與心率變率有不同的功能性核磁共振影像反應。我們的研究結果顯示,控制與自發性生理活動相關之能性核磁共振影像信號在取得更加敏感及特異性的阿茲海默症患者之默認網路模式特徵上非常重要。 Studies have reported that the Alzheimer's disease (AD) patients have different default mode network (DMN) characteristics from normal subjects. However, few studies considered the contamination of physiological noise in DMN characterization. Here, we study the impact of spontaneous physiology on characterizing the DMN of AD patients. Cardiac and respiratory cycles were respectively recorded using a pulse oximeter and a respiration belt concurrently with resting-state fMRI measurements. We used RETROICOR to remove phase-locked physiological artifacts. Other low frequency physiological effects of the same phase but different amplitudes (for respiration variations) or intervals (for heart rate) were corrected by RVHRCOR. Without correcting physiological noise, AD patients show significantly different DMN characteristics from the healthy subjects. However, this difference became less significant physiological noise correction. We also found that the physiological response functions were different between AD patients and healthy subjects. Our results suggest the importance of controlling spontaneous physiology in using hemodynamic responses to achieve more sensitive and specific characterization of the DMN in AD patients and healthy subjects. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/50817 |
DOI: | 10.6342/NTU201600705 |
Fulltext Rights: | 有償授權 |
Appears in Collections: | 醫學工程學研究所 |
Files in This Item:
File | Size | Format | |
---|---|---|---|
ntu-105-1.pdf Restricted Access | 4.43 MB | Adobe PDF |
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.