双次灌注法超声造影对兔VX2微小肝癌的观察

Contrast-enhanced ultrasound with double perfusion method in detection of rabbit VX2 micro-hepatocellular carcinoma

目的研究超声造影不同灌注法对直径〈10．0mm的兔VX2微小肝癌的检出率。方法将VX2瘤细胞接种于新西兰白兔大腿外侧皮下，制成荷瘤种兔并传代。将种兔VX2肿瘤在无菌条件下制成小瘤块，植入兔肝实质较厚处，制成带有VX2肿瘤的新西兰白兔30只，30只VX2肝肿瘤的新西兰白兔，分别经外周静脉采用单次和双次灌注法注射造影剂，与动物肝大体病理切面对照，观察不同造影方法检出微小肿瘤的敏感度。结果30只动物肝脏大体病理检查共检出41个微小肿瘤（其中3．0～5．0mm病灶15个，5．0～10．0mm病灶26个）。荷瘤兔肝VX2微小肿瘤超声造影增强方式呈“快进快退”表现，即在动脉相迅速增强，门脉相开始廓清，延迟相明显低于周围正常肝实质。其中单次灌注法共检出病灶数量为32个，其中3．0～5．0mm病灶7个，5．0～10．0mm病灶25个；双次灌注法共检出病灶数量为39个，其中3．0～5．0mm病灶13个，5．0～10．0mm病灶26个。单次和双次灌注法对微小肿瘤检出率分别为78％（32／41）和95％（39／41），差异具有统计学意义（，值为5．150，P值为0．023）。单次灌注法与双次灌注法对3．0～5．0mm病灶检出率分别为47％（7／15）和87％（13／15），差异具有统计学意义（X^2值为5．400，P值为O．025），对5．0～10．0mm病灶的检出率分别为96％（25／26）和100％（26／26），差异无统计学意义（X^2值为1．020，P值为0．500）。结论双次灌注法超声造影显著提高了微小肝癌（尤其是直径〈5．0mn病灶）的检出率。

Objective To study the detection rate of contrast-enhanced ultrasound （CEUS） with different perfusion methods on rabbit VX2 small hepatocellular carcinoma less than 10.0 mm. Methods VX2 tumor cells were inoculated into the subcutaneous tissue of New Zealand rabbit＇ s thigh. Then the plant tumor were cut into small blocks under sterile conditions and transplanted into hepatic parenchyma in 30 New Zealand rabbits. The contrast media was injected through peripheral vein by single and double perfusion methods. The detection rate of two methods were compared. Results There were 41 hepatocellular carcinoma lesions in the 30 rabbits. There were 15 lesions with size between 3.0 mm and 5.0 mm, and 26 lesions between 5.0 nun and 10.0 mm in diameter. On CEUS, the VX2 tumor presented fast-in and fast-out pattern. In arterial phase, the lesion was enhanced rapidly. In portal venous phase, contrast began to wash out from the carcinoma. In delay phase, the enhancement of lesion was significantly lower than the surrounding normal liver parenchyma. A total of 32 lesions were detected by single perfusion method, including 7 lesions ranging 3.0-5.0 mm and 25 lesions ranging 5.0-10.0 mm. A total of 39 lesions were detected by double perfusion method, including 13 lesions ranging 3.0-5.0 mm and 26 lesions ranging 5.0-10.0 mm. The detection rate of micro-hepatocellular carcinoma by single and double perfusion method was 78% and 95% respectively. The difference was statistically significant （X^2=5.150, P=0.023）. The detection rate of 3.0-5.0 mm lesions by single and double perfusion method was 47% and 87%, respectively. The difference was statistically significant （ X^2=5.400, P=0.025）. The detection rate of 5.0-10.0 mm lesions by single and double perfusion method was 96% and 100%, respectively. There was no statistically significant difference （X^2=1.020, P=0.500）. Conclusion The double perfusion method greatly promotes the detection of micro hepatocellular carcinoma, especially for the lesions less than 5.0 mm in diameter.