目的:探讨低剂量能谱计算机断层扫描(computed tomography,CT)单能量成像联合自适应统计迭代重建(adaptive statistical iterative reconstruction,ASiR)技术在兔VX2肝癌模型中的图像质量及对他的检出价值.方法:采用CT引导下穿刺法将VX...目的:探讨低剂量能谱计算机断层扫描(computed tomography,CT)单能量成像联合自适应统计迭代重建(adaptive statistical iterative reconstruction,ASiR)技术在兔VX2肝癌模型中的图像质量及对他的检出价值.方法:采用CT引导下穿刺法将VX2肝癌移植瘤植入24只新西兰大白兔肝左叶,于种植后14 d行能谱CT腹部增强扫描,采用40%ASiR重建动静脉期70 keV单能量图像,得到A组和B组图像.24 h后再对此批兔子行常规100kV腹部增强扫描,动静脉期图像使用滤波反投影(filtered back projection,FBP)算法重建,得到C组和D组图像.由两名放射学家对4组图像质量采用5分评分制法进行主观评分,观察者间一致性采用Kappa检验.测量4组图像背部肌肉标准差作为图像噪声,测量肝脏肿瘤信噪比(signal to noise ratio,SNR)和对比噪声比(contrast to noise ratio,CNR),A组与C组、B组与D组间均采用配对t检验比较.并记录两次扫描的CT剂量指数(CT dose index volume,CTDIvol)和有效辐射剂量(effective dose,ED),亦采用配对t检验比较.结果:22只大白兔种植成功,种植14 d后两种CT扫描均检出肿瘤24个.GSI模式扫描组有效辐射剂量较常规扫描组降低约27%(1.30 mSv±0.09 mSv vs 1.78 mSv±0.13 mSv,P=0.021).动脉期图像A组主观评分高于C组(4.09分±0.71分vs 3.80分±0.67分,P=0.049).静脉期图像B组主观评分高于D组(4.16分±0.67分vs 4.75分±0.65分,P=0.005).动脉期A组图像噪声低于C组(7.52 HU±1.12 HU vs 10.83 HU±2.17HU,P<0.001).静脉期B组图像噪声低于D组(8.25 HU±1.74 HU vs 11.55 HU±2.86 HU,P<0.001).A组肝肿瘤SNR和CNR均高于C组(P<0.05).B组肝肿瘤CNR高于D组,两组间SNR差异无统计学意义.结论:在兔VX2肝癌模型中,能谱CT单能量成像联合ASiR技术与常规扫描相比可降低辐射剂量,并提供良好的图像质量和肝癌病灶显示.展开更多
Objective: The purpose of this study was to evaluate the correlation between CT perfusion parameters and the hypoxia-inducible factor-1 alpha (HIF-1α), vascular en-dothelial growth factor (VEGF), matrix metalloprotei...Objective: The purpose of this study was to evaluate the correlation between CT perfusion parameters and the hypoxia-inducible factor-1 alpha (HIF-1α), vascular en-dothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and microvessel density (MVD) marked by CD34 molecular of rabbit VX2 liver tumors and to investigate the value of CT perfusion imaging in evaluating tumor angiogenesis. Material and methods: Twenty-four cases of rabbit VX2 liver tumor were performed by CT perfusion scanning. Hepatic artery perfusion (HAP), portal vein perfusion (PVP), total hepatic blood flow (THBF) and hepatic perfusion index (HPI) were measured by perfusion software. HIF-1α, VEGF and MMP-2 expression and MVD were detected in the 24 rabbit VX2 liver tumor tissue samples using immunohistochemical method. The correlation between the HIF-1α, VEGF, MMP-2 expression and MVD and CT perfusion parameters were analyzed. Results: Correlation analysis revealed that the expression of HIF-1α, MMP-2, MVD were positively related to the HAP, THBF, HPI (p < 0.01), but no relations with PVP (p > 0.05);and correlation analysis revealed that the expression of VEGF was positively related to the HAP, HPI (p 0.05). There was a positive relationship between the expression of HIF-1α, VEGF, MMP-2 and MVD (p < 0.01). Conclusions: CT perfusion imaging can reflect the blood perfusion of the rabbit VX2 liver tumors and evaluate the information of angiogenesis about tumors.展开更多
目的探讨125I粒子组织间植入诱导肝癌细胞凋亡的机制。比较不同活度125I粒子组织间植入诱导肿瘤细胞凋亡、抑制肿瘤细胞增殖的作用强度。方法将24只兔VX2肝癌模型随机分为3组,分别植入不同初始活度的125I粒子:0 m Ci组(对照组,n=8)、0.7...目的探讨125I粒子组织间植入诱导肝癌细胞凋亡的机制。比较不同活度125I粒子组织间植入诱导肿瘤细胞凋亡、抑制肿瘤细胞增殖的作用强度。方法将24只兔VX2肝癌模型随机分为3组,分别植入不同初始活度的125I粒子:0 m Ci组(对照组,n=8)、0.7 m Ci组(n=8)及1.0 m Ci组(n=8)。5周后处死实验兔,取出肿瘤病灶,检测125I粒子对肿瘤细胞凋亡、肿瘤生长相关因子表达的影响及caspase-3活性改变。结果不同初始活度125I粒子均可使肿瘤细胞凋亡率上升,Bcl-2、VEGF表达下调,Bax表达上调,1.0 m Ci125I粒子组作用均更加明显(P<0.05)。不同初始活度125I粒子可增加肿瘤组织中caspase-3活性,两治疗组间差异无明显统计学意义(P>0.05)。结论 125I粒子植入后不仅通过诱导肿瘤细胞凋亡抑制肿瘤生长、增殖,还影响凋亡相关基因及编码蛋白表达,抑制肿瘤细胞新生血管生成。展开更多
文摘目的:探讨低剂量能谱计算机断层扫描(computed tomography,CT)单能量成像联合自适应统计迭代重建(adaptive statistical iterative reconstruction,ASiR)技术在兔VX2肝癌模型中的图像质量及对他的检出价值.方法:采用CT引导下穿刺法将VX2肝癌移植瘤植入24只新西兰大白兔肝左叶,于种植后14 d行能谱CT腹部增强扫描,采用40%ASiR重建动静脉期70 keV单能量图像,得到A组和B组图像.24 h后再对此批兔子行常规100kV腹部增强扫描,动静脉期图像使用滤波反投影(filtered back projection,FBP)算法重建,得到C组和D组图像.由两名放射学家对4组图像质量采用5分评分制法进行主观评分,观察者间一致性采用Kappa检验.测量4组图像背部肌肉标准差作为图像噪声,测量肝脏肿瘤信噪比(signal to noise ratio,SNR)和对比噪声比(contrast to noise ratio,CNR),A组与C组、B组与D组间均采用配对t检验比较.并记录两次扫描的CT剂量指数(CT dose index volume,CTDIvol)和有效辐射剂量(effective dose,ED),亦采用配对t检验比较.结果:22只大白兔种植成功,种植14 d后两种CT扫描均检出肿瘤24个.GSI模式扫描组有效辐射剂量较常规扫描组降低约27%(1.30 mSv±0.09 mSv vs 1.78 mSv±0.13 mSv,P=0.021).动脉期图像A组主观评分高于C组(4.09分±0.71分vs 3.80分±0.67分,P=0.049).静脉期图像B组主观评分高于D组(4.16分±0.67分vs 4.75分±0.65分,P=0.005).动脉期A组图像噪声低于C组(7.52 HU±1.12 HU vs 10.83 HU±2.17HU,P<0.001).静脉期B组图像噪声低于D组(8.25 HU±1.74 HU vs 11.55 HU±2.86 HU,P<0.001).A组肝肿瘤SNR和CNR均高于C组(P<0.05).B组肝肿瘤CNR高于D组,两组间SNR差异无统计学意义.结论:在兔VX2肝癌模型中,能谱CT单能量成像联合ASiR技术与常规扫描相比可降低辐射剂量,并提供良好的图像质量和肝癌病灶显示.
文摘Objective: The purpose of this study was to evaluate the correlation between CT perfusion parameters and the hypoxia-inducible factor-1 alpha (HIF-1α), vascular en-dothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and microvessel density (MVD) marked by CD34 molecular of rabbit VX2 liver tumors and to investigate the value of CT perfusion imaging in evaluating tumor angiogenesis. Material and methods: Twenty-four cases of rabbit VX2 liver tumor were performed by CT perfusion scanning. Hepatic artery perfusion (HAP), portal vein perfusion (PVP), total hepatic blood flow (THBF) and hepatic perfusion index (HPI) were measured by perfusion software. HIF-1α, VEGF and MMP-2 expression and MVD were detected in the 24 rabbit VX2 liver tumor tissue samples using immunohistochemical method. The correlation between the HIF-1α, VEGF, MMP-2 expression and MVD and CT perfusion parameters were analyzed. Results: Correlation analysis revealed that the expression of HIF-1α, MMP-2, MVD were positively related to the HAP, THBF, HPI (p < 0.01), but no relations with PVP (p > 0.05);and correlation analysis revealed that the expression of VEGF was positively related to the HAP, HPI (p 0.05). There was a positive relationship between the expression of HIF-1α, VEGF, MMP-2 and MVD (p < 0.01). Conclusions: CT perfusion imaging can reflect the blood perfusion of the rabbit VX2 liver tumors and evaluate the information of angiogenesis about tumors.
文摘目的探讨125I粒子组织间植入诱导肝癌细胞凋亡的机制。比较不同活度125I粒子组织间植入诱导肿瘤细胞凋亡、抑制肿瘤细胞增殖的作用强度。方法将24只兔VX2肝癌模型随机分为3组,分别植入不同初始活度的125I粒子:0 m Ci组(对照组,n=8)、0.7 m Ci组(n=8)及1.0 m Ci组(n=8)。5周后处死实验兔,取出肿瘤病灶,检测125I粒子对肿瘤细胞凋亡、肿瘤生长相关因子表达的影响及caspase-3活性改变。结果不同初始活度125I粒子均可使肿瘤细胞凋亡率上升,Bcl-2、VEGF表达下调,Bax表达上调,1.0 m Ci125I粒子组作用均更加明显(P<0.05)。不同初始活度125I粒子可增加肿瘤组织中caspase-3活性,两治疗组间差异无明显统计学意义(P>0.05)。结论 125I粒子植入后不仅通过诱导肿瘤细胞凋亡抑制肿瘤生长、增殖,还影响凋亡相关基因及编码蛋白表达,抑制肿瘤细胞新生血管生成。
