Peng Song, Zhou Ping, He Wei, Liao Manqiong, Chen Lili, Ma C-M
Department of Diagnostic Imaging, The Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, People's Republic of China.
Phys Med Biol. 2016 Sep 21;61(18):6754-6769. doi: 10.1088/0031-9155/61/18/6754. Epub 2016 Aug 31.
The purpose of this study is to comparatively assess the thermal versus mechanical effects of pulsed high intensity focused ultrasound (HIFU) treatment on hepatic tumors in vivo. Forty-five rabbits with hepatic VX2 tumors were randomly separated into three groups (15 animals per group) before HIFU ablation. The total HIFU energy (in situ) of 1250 J was used for each tumor for three groups. In groups I and II, animals were treated with 1 MHz pulsed ultrasound at 1 Hz pulsed repetition frequency (PRF), 0.5 duty cycle (0.5 s on and 0.5 s off) and10 s duration for one spot sonication. For group II, in addition to HIFU treatment, microbubbles (SonoVue, Bracco, Milan, Italy) were injected via vein before sonication acting as a synergist. In group III, animals were treated with 1 MHz pulsed ultrasound at 10 Hz PRF, 0.1 duty cycle (0.1 s on and 0.9 s off) and 10 s duration for one sonication. The total treatment spots were calculated according to the tumor volume. Tumors were examined with contrast-enhanced computed tomography (CECT) immediately prior to and post HIFU treatment. Histopathologic assessment was performed 3 h after treatment. Our study showed that all animals tolerated the HIFU treatment well. Our data showed that mechanical HIFU could lead to controlled injury in rabbit hepatic tumors with different histological changes in comparison to thermal HIFU with or without microbubbles.
本研究的目的是在体内比较评估脉冲高强度聚焦超声（HIFU）治疗对肝肿瘤的热效应与机械效应。45只患有肝VX2肿瘤的兔子在HIFU消融术前被随机分为三组（每组15只动物）。三组中每个肿瘤均使用1250 J的总HIFU能量（原位）。在第一组和第二组中，动物接受1 MHz脉冲超声治疗，脉冲重复频率（PRF）为1 Hz，占空比为0.5（开0.5 s，关0.5 s），每次点超声处理持续10 s。对于第二组，除HIFU治疗外，在超声处理前经静脉注射微泡（声诺维，意大利布瑞柯公司，米兰）作为增效剂。在第三组中，动物接受1 MHz脉冲超声治疗，PRF为10 Hz，占空比为0.1（开0.1 s，关0.9 s），每次超声处理持续10 s。根据肿瘤体积计算总的治疗点数。在HIFU治疗前后立即用对比增强计算机断层扫描（CECT）检查肿瘤。治疗后3小时进行组织病理学评估。我们的研究表明，所有动物对HIFU治疗耐受性良好。我们的数据表明，与有或无微泡的热HIFU相比，机械HIFU可导致兔肝肿瘤可控性损伤，并伴有不同的组织学变化。
