【作者】 邢金子；

【导师】 刘爱连；

【作者基本信息】 大连医科大学 ， 影像医学与核医学， 2011， 硕士

【摘要】 目的:探讨3.0T血氧水平依赖功能MRI（fMRI-BOLD）技术对急性单侧输尿管梗阻大鼠肾血氧水平改变的评估。材料与方法:16只健康（Sprague Dawley ,SD）大鼠,体重为（336.6±14.5）g,10%水合氯醛,按照3.4ml/100g体重腹腔注射麻醉,其中3只因麻醉意外死亡出组,13只入组大鼠分别在结扎单侧输尿管前（梗阻前组）、结扎后1小时（梗阻后组）及解除结扎后1小时（解除组）进行常规MR轴位T2WI及冠状位BOLD序列扫描。观察T2WI像上不同组别间双肾皮髓质信号及解剖结构改变,分别进行不同组别间双肾皮、髓质信噪比对比分析;在ADW4.4工作站进行BOLD图像重建,测量三次扫描双肾皮髓质R₂^*值,分别进行不同组别间双肾皮质、髓质R₂^*值的对比分析。根据患侧肾盂扩张率不同,将其分为重度梗阻与轻度梗阻,并将其与R₂^*变化率进行对比分析;根据解除组患侧肾盂恢复率不同,将其分为缓解组与未缓解组,并分析其与梗阻程度及R₂^*变化率的关系。采用SPSS13.0软件配对t检验进行分析。结果:T2WI像上梗阻前组大鼠双肾皮质、髓质信噪比分别一致,左、右肾解剖结构清晰显示;梗阻后13只大鼠患侧肾实质信噪比均较梗阻前组明显增高（P<0.05）,皮、髓质分界欠清,肾盂均有不同程度扩张,健侧肾较梗阻前组未见明显变化;解除组患侧肾实质信噪比高于梗阻前组（P>0.05）,低于梗阻后组（P>0.05）,皮髓质分界清晰,肾盂扩张不同程度恢复,健侧肾较梗阻前组未见明显变化。梗阻前组大鼠左、右肾髓质R₂^*值分别为（33.65±5.22Hz,31.36±6.36Hz）,均高于相应肾皮质R₂^*值（25.41±4.62Hz,24.6±4.35Hz）,P<0.05;左肾与右肾皮质、髓质R₂^*值差异无统计学意义。梗阻后组患肾髓质R₂^*值（20.08±2.91Hz）低于梗阻前组髓质R₂^*值（P<0.05）,患侧肾皮质R₂^*值与梗阻前组皮质R₂^*值差异无统计学意义;健侧肾皮质R₂^*值（22.77±4.72Hz）略低于梗阻前肾皮质R₂^*值（P>0.05）,髓质R₂^*值（31.84±3.29Hz）略高于梗阻前组（P>0.05）。解除组患肾髓质R₂^*值（25.59±4.74Hz）低于梗阻前组髓质R₂^*值（P<0.05）,高于梗阻后组R₂^*值（P<0.05）,患侧皮质R₂^*值与梗阻前、后组皮质R₂^*值差异无统计学意义;解除组健侧肾皮质R₂^*值（22.24±3.60Hz）略低于梗阻后组,髓质R₂^*值（32.02±3.72Hz）略高于梗阻后组（P>0.05）。轻度梗阻R₂^*变化率低于重度梗阻。缓解组的梗阻程度及R₂^*变化率均低于未缓解组。结论:3.0T fMRI-BOLD技术通过测量R₂^*值能反映肾脏皮、髓质在正常情况下及急性单侧输尿管梗阻时氧代谢的变化,有助于理解其病理生理学机制,为早期单侧肾血氧水平改变的诊断提供可行的辅助手段,是一种简单、无创、可行的检查方法。更多还原

【Abstract】 Objective: To evaluate the renal oxygenation changes during acute unilateral ureteral obstruction in rats using blood oxygen level-dependent MR imaging（BOLD MRI） in 3.0 T MR.Methods: 16 healthy SD rats, 3 rats died because of anesthesia, 13 rats were performed kidney T2WI and coronal BOLD imaging respectively before UUO（obstruction former group）, 1hour afer UUO（obstruction group） and 1 hour after release of UUO （lift group）. Observed the signal and anatomical structure changes among the different groups of renal cortex and medulla, compared the SNR of renal parenchyma among three groups. BOLD images were reconstructed on 4.4 workstation, R₂^* values were determined in the cortex and medulla of the obstructed and the contrlateral nonobstructed kidneys, then comparative analysis of R₂^*values of renal cortex and medulla among different groups. According to the different affected side renal pelvis expansion rates, divided into mild obstruction and severe obstruction, then compared with the rate of R₂^* values changes; according to the different renal pelvis recovery rate, divided into relief group and no relief group, then analyze the relationship with obstructions and R₂^* changes.Results: The SNR between left and right renal were the same, and renal anatomy were showed clearly before UUO . After UUO the SNR of 13 rats affected side renal was significantly higher than before, the boundaries of cortex and medulla show blurry, and the pelviectasis in varying degrees. After release of UUO, the SNR higher than the obstruction former group, lower than the obstruction group, the boundaries got clearly, and the renal pelvis recovery in varying degrees. Before UUO, the R₂^* values of medulla was significantly higher than that of renal cortex, but during the UUO was associated with a decreased R₂^*in medulla, and after release of obstruction the medulla Objective: To evaluate the renal oxygenation changes during acute unilateral ureteral obstruction in rats using blood oxygen level-dependent MR imaging（BOLD MRI） in 3.0 T MR.Methods: 16 healthy SD rats, 3 rats died because of anesthesia, 13 rats were performed kidney T2WI and coronal BOLD imaging respectively before UUO（obstruction former group）, 1hour afer UUO（obstruction group） and 1 hour after release of UUO （lift group）. Observed the signal and anatomical structure changes among the different groups of renal cortex and medulla, compared the SNR of renal parenchyma among three groups. BOLD images were reconstructed on 4.4 workstation, R₂^* values were determined in the cortex and medulla of the obstructed and the contrlateral nonobstructed kidneys, then comparative analysis of R₂^*values of renal cortex and medulla among different groups. According to the different affected side renal pelvis expansion rates, divided into mild obstruction and severe obstruction, then compared with the rate of R₂^* values changes; according to the different renal pelvis recovery rate, divided into relief group and no relief group, then analyze the relationship with obstructions and R₂^* changes.Results: The SNR between left and right renal were the same, and renal anatomy were showed clearly before UUO . After UUO the SNR of 13 rats affected side renal was significantly higher than before, the boundaries of cortex and medulla show blurry, and the pelviectasis in varying degrees. After release of UUO, the SNR higher than the obstruction former group, lower than the obstruction group, the boundaries got clearly, and the renal pelvis recovery in varying degrees. Before UUO, the R₂^* values of medulla was significantly higher than that of renal cortex, but during the UUO was associated with a decreased R₂^*in medulla, and after release of obstruction the medulla更多还原