本文關(guān)鍵詞：大鼠非酒精性脂肪肝的IDEAL-IQ和MRS評價　出處：《鄭州大學(xué)》2016年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 大鼠 非酒精性脂肪肝 磁共振成像 對比劑 MRS IDEAL-IQ

【摘要】：背景和目的隨著生活方式的改變和生活水平的提高,肥胖和脂肪肝人群比例逐漸上升。非酒精性脂肪肝病(Non-Alcoholic Fatty Liver Disease,NAFLD)已成為社會的通病。脂肪肝是可逆性病變,因此,早期診斷和治療脂肪肝是非常必要的,以防止肝脂肪變性的進(jìn)一步發(fā)展。肝臟病理穿刺是診斷脂肪肝評估的金標(biāo)準(zhǔn)。然而,病理穿刺具有創(chuàng)傷性,所以病理穿刺不能作為篩查和長期病情監(jiān)測的檢查方法。因此,學(xué)者正在研究非侵入性的方法來測量脂肪含量。中華醫(yī)學(xué)會2006年制定脂肪肝分級:F0(正常肝臟):脂肪變的肝細(xì)胞小于5%;F1:脂肪變的肝細(xì)胞為5%-30%,F2(輕度脂肪肝):脂肪變的肝細(xì)胞為31%-50%,F3(中度脂肪肝):脂肪變的肝細(xì)胞為51%-75%,F4(重度脂肪肝):脂肪變的肝細(xì)胞大于75%。目前能無創(chuàng)性測量脂肪含量的方法:超聲(Ultrasound,US),計算機(jī)斷層掃描(CT),MRI。超聲(US)對輕度脂肪變性不敏感、主觀性高,缺乏客觀指標(biāo)。計算機(jī)斷層掃描(Computed Tomography,CT)具有輻射性,不能作為篩查和長期病情監(jiān)測的檢查方法。磁共振成像被認(rèn)為是肝臟脂肪的非侵入性檢測和定量優(yōu)越的成像方法。目前用于脂肪肝評估的MRI的序列主要有:正反相位、MRS、IDEAL、IDEAL-IQ。材料與方法1.隨機(jī)選取60只清潔級健康雄性SD大鼠,大鼠平均周齡5.5周齡。體重94.6±8.9 g。實驗動物均由鄭州大學(xué)動物實驗中心提供。按照隨機(jī)數(shù)字表法將大鼠分為實驗組(46只)和對照組(14只),實驗組高脂飲食8周、12周,對照組正常飲食8、12周。按照掃描注射對比劑的濃度,大鼠又分為:低劑量組、中等劑量組、高劑量組。2.磁共振掃描:美國GE公司Discovvery MR 750 3.0T超導(dǎo)高場磁共振掃描機(jī)。掃描線圈:膝關(guān)節(jié)線圈。每組大鼠均在8周、12周行磁共振。掃描的序列有:T1加權(quán)成像(T1-Weighted Imaging,T1WI)、T2加權(quán)成像(T2-weighted imaging,T2WI)、彌散加權(quán)成像(Diffusion Weighted Imaging,DWI)、波譜(Magnetic Resonance Spectroscopy,MRS)、IDEAL-IQ。然后尾靜脈注射對比劑,注射對比劑后1 min、3 min行IDEAL-IQ掃描。在掃描結(jié)束后解剖去肝臟組織,進(jìn)行石蠟包埋,常規(guī)切片,行HE染色。3.后處理:通過通過GE后處理工作站進(jìn)行后處理:1、SAGE 7.0軟件處理MRS獲得脂峰下面積,通過計算得出脂肪含量;2、IDEAL-IQ進(jìn)行后處理,在對應(yīng)MRS掃描時定位體素塊相應(yīng)位置選擇感興趣區(qū)得到脂肪比值;3、對注射對比劑前后各個時間點的IDEAL-IQ相對應(yīng)的位置選擇感興趣區(qū)得到脂肪比值和R2*值。4、光鏡下觀察病理切片,按照脂肪浸潤的肝細(xì)胞數(shù)量占肝細(xì)胞總數(shù)的比例進(jìn)行分級。4.實驗數(shù)據(jù)運用SPSS17.0軟件進(jìn)行統(tǒng)計學(xué)分析,實驗數(shù)據(jù)采用均數(shù)±標(biāo)準(zhǔn)差表示。采用簡單線性回歸分析MRS測得的脂肪比值(Fat Fraction,FF)(即峰下面積比值)、IDEAL-IQ測得的脂肪比值(Fat Fraction,FF)分別與大鼠脂肪肝病理程度的相關(guān)性。采用ROC分析評價MRS、IDEAL-IQ診斷非酒精性脂肪肝的最佳界點。同一劑量組各個時間點的脂肪相對含量及R2*之間的比較采用重復(fù)測量方差分,同一測量時間不同組脂肪相對含量及R2*之間的比較采用單因素方差分析,并采用L-SD檢驗進(jìn)一步兩兩比較。P0.05提示差異有統(tǒng)計學(xué)意義。結(jié)果1.F0(脂肪變的肝細(xì)胞為5%)為Ⅰ級:9只;F1:脂肪變的肝細(xì)胞為5%-30%為Ⅱ級:11只;F2(脂肪變的肝細(xì)胞為31%-50%)為Ⅲ級:21只;F3(脂肪變的肝細(xì)胞為51%-75%)為Ⅳ級:13只;F4(脂肪變的肝細(xì)胞大于75%)為Ⅴ級:6只。2.IDEAL-IQ、MRS結(jié)果:(1).FF-IDEAL-IQⅠ級:4.63±0.60%;Ⅱ級:6.48±0.61%;Ⅲ級:9.10±1.89%;Ⅳ級:18.94±6.24%;Ⅴ級:37.67±6.17%。FF-IDEAL-IQ值與病理結(jié)果呈正相關(guān)(R=0.825,p0.01),ID IQ判定大鼠脂肪肝的閾值為7.31%。(2).FF-MRS:Ⅰ級:4.24±1.69%:Ⅱ級;7.90±1.90%;Ⅲ級:13.18+3.83%;Ⅳ級:20.71+10.15%:Ⅴ級:39.10±9.09%。FF-MRS與病理結(jié)果呈正相關(guān)(R=0.796,p0.01),MRS判定大鼠脂肪肝的閾值為10.56%。IDEAL-IQ與大鼠脂肪肝的病理程度相關(guān)性高于MRS。3.FF-IDEAL-IQ:(1).低劑量組:注射對比劑前與注射對比劑后1 min,3 min的差異均無統(tǒng)計學(xué)意義(F=2.280,P=0.116);(2).中等劑量組:注射對比劑前與注射對比劑后1 min,3 min的差異均無統(tǒng)計學(xué)意義(F=2.28,P=0.181);(3).高劑量組:注射對比劑前與注射對比劑后1 min,3 min的差異均無統(tǒng)計學(xué)意義(F=2.554,P=0.091)。(4).注射對比劑前:各劑量組FF的差異無統(tǒng)計學(xué)意義(F=0.108,P=0.898),(5).注射對比劑后1 min:各劑量組FF的差異無統(tǒng)計學(xué)意義(F=0.337,P=0.72)。(6).注射對比劑后3 min:各劑量組FF的差異無統(tǒng)計學(xué)意義(F=0.209,P=0.812)。4.R2*值:(1).低劑量組:注射對比劑前與注射對比劑后1min,3min的差異均有統(tǒng)計學(xué)意義(F=163.300,P=0.000);(2).中等劑量組:注射對比劑前與注射對比劑后1 min,3 min的差異均有統(tǒng)計學(xué)意義(F=347.457,P=0.00);(3).高劑量組:注射對比劑前與注射對比劑后1min,3 min的差異均有統(tǒng)計學(xué)意義(F=380.586,P=0.091);(4).注射對比劑前:各劑量組R2*值的差異無統(tǒng)計學(xué)意義(F=1.912,P=0.157);(5).注射對比劑后1 min:各劑量組R2*值的差異有統(tǒng)計學(xué)意義(F=5.236,P=0.008);(1).注射對比劑后3 min:各劑量組R2*值的差異有統(tǒng)計學(xué)意義(F=0.209,P=0.812)。結(jié)論1.FF-MRS與NAFL病理結(jié)果呈正相關(guān),MRS診斷脂肪肝的閾值為10.56%。2.FF-IDEAL-IQ與NAFL病理結(jié)果呈正相關(guān),IDEAL-IQ診斷脂肪肝的閾值為7.31%。3.DEAL IQ與大鼠脂肪肝的病理程度相關(guān)性高于MRS。4.低劑量、中等劑量、高劑量對比劑對大鼠脂肪肝模型中的FF-IDEAL-IQ值均無影響。5.IDEAL-IQ測量脂肪含量具有穩(wěn)定性。
[Abstract]:Background and objective: with the change of lifestyle and the improvement of living standards, the proportion of the fatty liver and obesity increased gradually. Nonalcoholic fatty liver disease (Non-Alcoholic Fatty Liver Disease, NAFLD) has become a social problem. Fatty liver is a reversible disease, therefore, early diagnosis and treatment of fatty liver is very necessary, in order to prevent the further development of fatty degeneration of the liver. The liver pathological biopsy is the gold standard for the diagnosis of fatty liver assessment. However, pathological biopsy is traumatic, so cannot be used as a method in the screening of pathological biopsy and long-term monitoring. Therefore, scholars are studying a non-invasive method to measure the fat content. The Chinese Medical Association in 2006 to develop fatty liver: classification F0 (normal liver): less than 5% of fatty liver cell fatty degeneration of liver cells; F1: 5%-30%, F2 (mild fatty liver): fatty degeneration of liver cells of 31%-50%, F3 (moderate fat Fatty liver): fatty degeneration of liver cells of 51%-75%, F4 (severe fatty liver): fatty degeneration of liver cells than 75%. currently can be a non-invasive method of measuring fat content: ultrasound (Ultrasound, US), computed tomography (CT), MRI. ultrasound (US) is not sensitive to mild fatty degeneration of subjectivity high, the lack of objective indicators. Computed tomography (Computed Tomography, CT) with radiation, can not be used as a method in the screening and long-term monitoring. Magnetic resonance imaging is non-invasive detection and quantitative imaging of fatty liver. The superior method currently used to evaluate the MRI sequence of fatty liver are: positive and negative MRS, IDEAL, IDEAL-IQ. phase, materials and methods of 1. randomly selected 60 clean grade healthy male SD rats, rats 5.5 weeks of age. The average age of 94.6 + 8.9 g. body weight of experimental animal by the Zhengzhou University animal experimental center. According to the random number table will be The rats were randomly divided into experimental group (46 rats) and control group (14 rats) and experimental group with high fat diet for 8 weeks, 12 weeks, the control group with normal diet 8,12 weeks. According to the concentration of scan contrast injection, rats were divided into low dose group, medium dose group, high dose group of.2. magnetic resonance scanning American GE company Discovvery MR 750 3.0T high field superconducting magnetic resonance scanner. Scanning coil: knee coil. The rats were 8 weeks, 12 weeks. Magnetic resonance scanning sequence: T1 weighted imaging (T1-Weighted Imaging, T1WI), T2 (T2-weighted imaging, T2WI weighted imaging, diffusion weighted) imaging (Diffusion Weighted Imaging, DWI (Magnetic), Resonance Spectroscopy, MRS spectrum, IDEAL-IQ.) and intravenous injection of contrast agent, after contrast agent injection 1 min, 3 min IDEAL-IQ scanning. After scanning the anatomy to liver tissue were embedded in paraffin, paraffin sections, stained with HE.3. postprocessing by: by GE Postprocessing workstation for postprocessing: 1, SAGE 7 software MRS lipid peak area, obtained by calculating the fat content; 2, IDEAL-IQ postprocessing, positioning in the corresponding MRS scanning voxel block corresponding to the position selection of region of interest are fat ratio; 3, to get fat injection ratio and R2* value of.4 the corresponding ratio of agent before and after each time point IDEAL-IQ to choose the location of region of interest, the pathological observation under light microscope, grading.4. experimental data using SPSS17.0 statistical analysis software according to the fatty infiltration of the liver cells accounted for the proportion of the total number of liver cells, the experimental data expressed by the mean and standard deviation. The regression analysis of fat the ratio of MRS measured by simple linear (Fat Fraction, FF) (i.e. peak area ratio), the ratio of fat measured by IDEAL-IQ (Fat Fraction, FF) were correlated with the pathological degree of fatty liver in rats. Using ROC analysis 璇勪環(huán)MRS,IDEAL-IQ璇婃柇闈為厭綺炬，

本文編號：1400213