HAN Hong, JIN Yun-jie, LIU Rong, FAN Zhuo-yang, JI Zheng-biao, WANG Wen-ping
Objective To explore the value of quantitative analysis technique of contrast-enhanced ultrasound in early differentiation of residual tumor from inflammatory rim after laser ablation of rabbit VX2 liver tumors.Methods VX2 tumors were implanted on the livers of 16 New Zealand white rabbits, followed by laser ablation to create a partial ablation model of liver tumors.And then contrast-enhanced ultrasonography was performed at 1, 3, 7, and 14 days after ablation.The examination instrument was Toshiba Aplioi900 ultrasonic apparatus, and the ultrasonic contrast agent was SonoVue. Referring to the final pathological specimen, the images were replayed, and the regions of interest (ROI) were selected in normal liver, residual tumor, and hyperemic inflammatory rim for quantitative analysis respectively.The morphology of the time intensity curve(TIC) and the differences in the values of each quantitative parameter were compared between the residual tumor and the hyperemic inflammatory rim after ablation.Results A total of 70 ROI were delineated at different time points of 1, 3, 7 and 14 days after ablation, including 34 residual tumors and 36 inflammatory zones. The morphology of TIC was different between the residual tumor and the inflammatory rim around the ablation zone.The most common TIC morphology of contrast-enhanced ultrasound in residual tumor was the rapid rise and rapid fall type (22/34, 64.7%), while that of inflammation zone was the rapid rise and slow fall type (20/36, 55.6%) (P=0.002). On the third day after ablation, the quantitative parameters of contrast-enhanced ultrasound including peak intensity, time to peak, mean transit time, area under the curve, area under the curve of wash in and area under the curve of wash out were significantly different between the residual tumor and inflammatory zone (all P < 0.05).Conclusion Quantitative analysis of contrast-enhanced ultrasound has certain value in early differentiation of residual tumor and inflammatory rim after ablation of rabbit VX2 liver tumors.
