著者

山本 聡 牧野 雄一 清水 太一 川本 祥太郎 小野木 真哉 桝田 晃司

出版者

一般社団法人 日本コンピュータ外科学会

雑誌

日本コンピュータ外科学会誌 (ISSN:13449486)

巻号頁・発行日

vol.23, no.1, pp.15-22, 2021 (Released:2021-02-04)

参考文献数

22

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The purpose of this study is to develop a support software to place ultrasound transducer, which produces local acoustic radiation force, for active induction of a micro object, representing a thin catheter, through blood vessel network. First, based on the image analysis of 3D blood vessel network, which was obtained using echography, the system calculates the possible area of the ultrasound transducer to be able to induce a micro object to desired path in blood vessel network. Meanwhile, due to the shape of body surface and the position of the ribs, which was obtained by an optical position sensor, the common area with the body surface was derived. Then, considering the position and the movable area of the robot, which grasps and moves the ultrasound transducer, the system indicates the candidate commands for the robot. To verify the system performance, we have conducted a simulation for active induction experiment of thin catheter through blood vessel network of a normal volunteer subject. As the result, we confirmed the variation of the thin catheter induction according to both body posture and breathing condition.

著者

出町 文 重原 伸彦 江田 廉 澤口 冬威 望月 剛 桝田 晃司 宮本 義孝 千葉 敏雄

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.51, no.6, pp.374-383, 2013-12-10 (Released:2014-03-28)

参考文献数

20

被引用文献数

2

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We have previously reported our attempts for active control of microbubble aggregations, by making use of Bjerknes force, which acts to propel microbubbles and to adjust the size of aggregations. However, because we have used simple shape of artificial blood vessels, the behavior of aggregations in a capillary, e.g., probability to obstruct in bloodstream, possibility of embolization, has not been predicted. Thus we measured the sticked area of produced aggregation on a wall of artificial blood vessel before evaluating the volume flown to downstream. First we prepared the straight path model of artificial blood vessel with the diameter of 2 mm to produce aggregation by emitting ultrasound against flow, which conditions were with 5 MHz and 300-500 kPa-pp. The size of aggregation increased according to the sound pressure, whereas there would be an optimal flow velocity and suspension density to obtain maximum trapped performance. The flat rate of aggregation showed that sound pressure works to compress the shape of aggregation rather than the effect of flow velocity. Then we derived the conditions to obtain a desired volume of aggregation to apply to the multi-bifurcation model of artificial blood vessel, which has repeatedly divided paths until the middle of the model from the inflow path of 2 mm to the minimum diameter of 0.5 mm, to confirm the behavior of an aggregation. Using the flow velocity of 20 mm/s, maximum sound pressure of 300 kPa, and suspension density of 0.08 μl/ml, the volume of aggregation was expected to be 0.6 mm3, which is greater than the section area of the narrow path in the bifurcation model. The result showed that the aggregation, in 50 s after the injection of the suspension, flaked off the vessel wall, flew to downstream, and was caught at a bifurcation. Finally we clearly confirmed that the aggregation blocked a path, where colored water could not penetrate to downstream.