“…By making use of microbubble aggregations, the effects of ultrasound therapy would be expected by accelerating the temperature increase in thermal therapy [1,2] and inducing sonoporation [3] to allow the uptake of larger molecules into cells in physical drug delivery [4,5]. Though the mechanism to form aggregation is very complex, because of the connection among various parameters, various researches related to microbubble aggregations were experimentally and theoretically investigated [6][7][8][9][10][11]. However, because of the difficulty to produce a capillary-mimicking artificial blood vessel, the behavior of aggregations in a capillary, e.g., probability to obstruct in bloodstream, shape destruction of the aggregation, etc, has not been predicted.…”