Sasaki Kazuaki, Medan Mohamed S, Azuma Takashi, Kawabata Ken-ichi, Shimoda Minoru, Umemura Shin-ichiro
Central Research Laboratory, Hitachi, Ltd., Tokyo, Japan.
J Vet Med Sci. 2006 Oct;68(10):1069-74. doi: 10.1292/jvms.68.1069.
We fabricated a prototype 3.25-MHz split-focus therapeutic transducer combined with a small 6.5-MHz imaging ultrasonic probe for transrectal treatment of prostate cancer and evaluated the feasibility of using split-focus high-intensity focused ultrasound (HIFU) to ablate localized tumor tissue without injuring the surrounding organs. We therefore established a localized tumor model by inoculating VX2 tumor into rabbit livers. The localized VX2 tumors of nine rabbits were transdermally treated with split-focus ablation at a peak intensity in water of 6 kW/cm2 for 4 s (6 shots) under the guidance of ultrasonic B-mode imaging. Necropsy a day after treatment found the surface of the livers and gastrointestinal tracts to be grossly normal. The VX2 tumors were completely coagulated and were surrounded by ablated liver tissue. The six shots of split-focus HIFU destroyed the VX2 tumors without injuring the liver surfaces or the surrounding organs. These results suggest that split-focus HIFU ablation could be an effective treatment of localized tumors.
我们制造了一个3.25兆赫兹的分裂聚焦治疗换能器原型，它与一个小型6.5兆赫兹的成像超声探头相结合，用于经直肠治疗前列腺癌，并评估了使用分裂聚焦高强度聚焦超声（HIFU）消融局部肿瘤组织而不损伤周围器官的可行性。因此，我们通过将VX2肿瘤接种到兔肝脏中建立了局部肿瘤模型。在超声B模式成像引导下，对9只兔子的局部VX2肿瘤进行经皮分裂聚焦消融治疗，水中峰值强度为6千瓦/平方厘米，持续4秒（6次发射）。治疗后一天进行尸检发现肝脏和胃肠道表面大体正常。VX2肿瘤完全凝固，周围是消融的肝组织。6次发射的分裂聚焦HIFU摧毁了VX2肿瘤，而未损伤肝脏表面或周围器官。这些结果表明，分裂聚焦HIFU消融可能是治疗局部肿瘤的有效方法。
