中文摘要：

目的：应用对比剂动力学时间分辨成像（Time Resolved Imaging of Contrast Kinetics，TRICKS）技术增强磁共振血管成像（MR angiography．MRA）及弥散加权成像（Diffusion Weighted Imaging，DWI）技术活体动态监测兔VX2肌肉肿瘤生物学生长与血管生成，探讨肿瘤血管生成与肿瘤生长的关系。方法：30只新西兰白兔，每只均在右后腿肌肉内接种VX2肿瘤细胞1×10^7建立肿瘤模型。分别在肿瘤接种后第4、7、10、13、16天（每个时间点6只）分别进行T1WI、T2WI、DWI、TRICKS动态增强MRA及T1WI增强延迟扫描．活体监测兔VX2肌肉肿瘤血管生成，肿瘤标本HE及CD3l免疫组化染色进行验证。两住医师双盲法分别测量不同生长点肿瘤的长、短径及体积，并与大体病理标本比较；测定TRICKS增强动态MRA所能显示肿瘤血管的最小直径及形态变化；观察ADC值变化与肿瘤生长的关系。结果：（1）ADC值随着肿瘤体积的长大而逐渐增大。（2）MRI活体测定肿瘤大小与病理大体标本所测算肿瘤体积的差异无显著性。（3）TRICKS增强MRA动态显示肿瘤血管的最小直径为：0．85±0．12mm。（4）肿瘤血管生成具有从单一细小的胚芽到增多、增粗环绕肿瘤，直到形成扭曲、紊乱的肿瘤血管团的规律。结论：TRICKS增强MRA可实现对肿瘤生长与肿瘤血管生成的形态学监测。ADC值变化与肿瘤生长、坏死的生物学进程有一定的相关性。

英文摘要：

Objective：To study the feasibility of dynamic monitoring tumor growth and angiogenesis by time resolved imaging of contrast kinetics （TRICKS） and diffusion weighted imaging （DWI） technique on a 3T MR system in vivo, and elucidate the relationship between tumor angiogenesis and tumor growth. Methods：Thirty New Zealand white rabbits were implanted VX2 tumors in the right thigh muscle, then the rabbits received T1WI, T2WI, DWI, TRICKS enhanced MR angiography （MRA）and T1WI enhanced delaying scanning on 3T MR at 4, 7, 10, 13, 16 days （n=6 each time point） respectively after tumor implantation. The tumor angiogenesis were detected through imaging analysis in vivo. The results were verified by HE staining and CD31 immunohistochemistry of tumor tissue. The volume of tumor measured by MR images and tumor specimens were compared by two radiologist with double blind method. Also the morphologie process of tumor angiogenesis and changes of ADC value were monitored and analyzed. Results：（1） The ADC value was increasing with the tumor growing. （2） The volume of tumors measured by MR images and tumor specimens had no statistical significance. （3） The minimum diameter of tumor vessels displayed on MRA images was 0.85± 0.12mm. （4） The morphologic process of tumor angiogenesis was demonstrated as sprouting from pre-existing blood vessel, forming lots of new vessels around tumor, and forming the immature vessels web with lots of tortuous, dilated, irregular vessels penetrating into the tumor at last. Conclusions： The tumor growth and tumor angiogenesis morphology can be monitored by TRICKS-enhanced MRA. ADC value has a certain correlation with the biological process of tumor growth and necrosis.