本文選題：輕度認(rèn)知功能障礙 + 小世界特性　； 參考：《中國(guó)醫(yī)學(xué)影像技術(shù)》2014年05期

【摘要】：目的應(yīng)用靜息態(tài)fMRI觀察輕度認(rèn)知功能障礙(MCI)患者大腦功能網(wǎng)絡(luò)是否具有小世界特性。方法采集13例MCI患者(MCI組)和17名正常老年人(NC組)的大腦靜息態(tài)BOLD-fMRI數(shù)據(jù)。采用SPM 5軟件對(duì)圖像進(jìn)行預(yù)處理,將大腦分割為90個(gè)區(qū)域,計(jì)算90個(gè)區(qū)域間的相關(guān)系數(shù)。以矩陣稀疏度(Sparsity)為閾值,將相關(guān)矩陣轉(zhuǎn)換為網(wǎng)絡(luò)。計(jì)算網(wǎng)絡(luò)的聚類系數(shù)(C)和平均路徑長(zhǎng)度(L),若滿足γ=C/Crand1且λ=L/Lrand≈1(rand代表相應(yīng)隨機(jī)網(wǎng)絡(luò)),為則認(rèn)為大腦功能網(wǎng)絡(luò)具有小世界特性。采用雙樣本t檢驗(yàn)比較MCI組與NC組大腦功能網(wǎng)絡(luò)小世界參數(shù)的差異。結(jié)果在0.10~0.40閾值范圍內(nèi),MCI組和NC組均符合γ1且λ≈1。MCI組γ和δ均大于NC組,且在0.10≤Sparsity≤0.18時(shí)差異有統(tǒng)計(jì)學(xué)意義(P0.05);MCI組λ在各閾值處均小于NC組,在Sparsity=0.18、0.28和0.32處差異有統(tǒng)計(jì)學(xué)意義(P0.05)。結(jié)論 MCI患者大腦fMRI網(wǎng)絡(luò)具有小世界特性,且與正常老年人相比有所增強(qiáng)。
[Abstract]:Objective to observe the small world characteristics of cerebral functional network in patients with mild cognitive impairment (MCI) by resting fMRI. Methods brain resting BOLD-fMRI data of 13 MCI patients (MCI group) and 17 normal elderly (NC group) were collected. SPM5 software was used to preprocess the image. The brain was divided into 90 regions and the correlation coefficients between 90 regions were calculated. The correlation matrix is transformed into a network using matrix sparsity as the threshold. The clustering coefficient (C) and the average path length (L) of the network are calculated. If 緯 C / Cr and 位 L / L rand 鈮，

本文編號(hào)：2091063