采用诊断超声激励微泡的方法增强肿瘤组织的血流灌注，增加肿瘤组织局部阿霉素的释放。

选取健康雄性SD大鼠10只，双侧大腿内侧皮下种植Walker-256肿瘤20个，随机配对分为对照组（10例）与超声治疗组（10例）。治疗前后分别进行超声造影，对超声造影图像进行定量分析。治疗后获取部分肿瘤组织后行高效液相色谱法检测肿瘤组织的药物浓度，另外采用冰冻切片观察肿瘤组织内阿霉素的荧光强度。治疗组与对照组定量分析峰值强度（PI）、曲线下面积（AUC）及阿霉素药物质量浓度比较，采用配对t检验。

（1）超声治疗后视觉造影效果中，6个明显增强，4个无明显变化，定量分析PI及AUC明显高于治疗前（PI：75.74±17.67 vs 66.22±16.25，AUC：3354.91±796.15 vs 2937.52±677.51），差异均有统计学意义（t=-5.212、-5.259，P均<0.001）；（2）治疗组阿霉素药物质量浓度是对照组的1.2倍[（1.15±0.25）μg/g vs（0.96±0.21）μg/g]，差异有统计学意义（t=2.403，P<0.05）；（3）各组肿瘤组织光镜下表现：肿瘤细胞排列成条索状，核大深染，治疗组可见血管充血，有少量炎症细胞浸润；（4）激光共聚焦显微镜下可见治疗组肿瘤组织间质中外漏的阿霉素荧光明显多于对照组。

诊断超声激励微泡治疗可增强大鼠Walker-256肿瘤的血流灌注，有助于化疗药物局部释放。

To improve the chemotherapy drug delivery to tumor by enhancing the tumor vascular perfusion induced by diagnostic ultrasound combined with microbubbles.

Ten healthy male sprague-dawley (SD) rats with total twenty walker-256 tumors implanted in the two back legs were randomized to the two paired groups: controlled group (C, n=10) and treatment group (T, n=10). Tumors in the controlled group were ultrasonic sham operated, while in the treatment group were treated by diagnostic ultrasound combined with microbubbles. The treatment group were taken contrast-enhanced ultrasound (CEUS) before and after treatment and analyzed the quantitative parameters. The microbubbles used in the treatment and CEUS was a kind of self-made lipid microbubbles called Zhifuxian. The 0.02 ml microbubbles were bolus injected at CEUS, while during treatment, 0.04 ml microbubbles diluted into 1 ml saline solution were injected slowly at constant speed. Flushed by saline solution after treatment, the rats′ tumors were harvested into three parts: one for chemotherapy drug concentration detected by high performance liquid chromatography (HPLC), one for HE detection, and one for Dox fluorescence intensity detected by confocal laser scanning microscopy (CLSM). The peak intensity (PI) values, the area under curve (AUC) values and the Dox concentration of each group were analyzed by pared-samples t test.

(1) The contrast enhanced ultrasound quantitative analysis of the T group: PI value of the tumors before and after treatment were 66.22±16.25 and 75.74±17.67. The AUC values were 2937.52±677.51 and 3354.91±796.15. There was significant statistical difference between them (t=-5.212, -5.259, all P<0.05). (2) The Dox concentration of the T and C groups were (1.15±0.25) ug/g and (0.96±0.21) ug/g. There was significant statistical difference between them (t=2.403, P<0.05). The Dox concentration of the treatment group was 1.2 times of the controlled group. (3) The pathology results of T and C groups: the tumor cells were arranged in cords, with big round deep-stained nucleus. No pathological changes were observed in the controlled group, and there was no significant difference between the two groups. But in the treatment group, tumor vascular congestion and inflammatory cell infiltration could be observed. (4) The confocal laser scanning microscopy (CLSM) detection of the T and C groups: the Dox red fluorescence was distributed in the tumor tissue interstitial, and the fluorescence intensity and distribution area of the treatment group were significant higher than the controlled group.

Diagnostic ultrasound combined with microbubbles treatment could significantly increase the blood perfusion in the walker-256 tumors of SD rats. Taking advantage of this vascular effect, the chemotherapy drug Dox could be delivered much more to the tumor tissue along with circulating bloodstream. With the addition of the sonoporation effect induced by the cavitation of the microbubbles, the chemotherapy drugs could be released much more to the tumor interstitial tissue.