高强度聚焦超声立体定向治疗并联机器人对离体猪肝脏组织的损伤效应

Injury effects in porcine liver tissue in vitro by 3D-guided HIFU treatment parallel robot

目的探讨自主研制的高强度聚焦超声立体定向治疗并联机器人在换能器摆动模式下对离体猪肝脏组织的损伤效应。方法离体猪肝脏组织分为换能器摆动组和换能器固定组,采用该装置在不同辐照时间和辐照深度下分别进行定点脉冲辐照,测量生物学焦域体积及其中心距组织表面距离,并取靶区组织进行病理学检查。比较两组间生物学焦域体积测值以及换能器摆动组生物学焦域中心距组织表面的距离与预设辐照深度间的差异,并分析辐照深度及辐照时间对生物学焦域的影响。结果辐照靶区形成凝固性坏死区,与周围组织分界清楚。在相同辐照剂量下,两组所产生的生物学焦域体积测值间差异无统计学意义(P>0.05)。生物学焦域中心距组织表面的距离与预设辐照深度间差异无统计学意义(P>0.05)。在相同辐照参数下,生物学焦域体积随辐照时间增加而增大,随辐照深度增加而减小。结论高强度聚焦超声立体定向治疗并联机器人在换能器摆动模式下对离体猪肝脏组织可产生有效、精确的损伤,生物学焦域与辐照时间和辐照深度有关。

Objective To assess injury effects of porcine liver in vitro in rotary radiation mode with studied 3D-guided HIFU treatment parallel robot.Methods In vitro porcine liver tissues were divided into two groups regarding the rotary radiation mode and the fixed position radiation mode.All tissues were irradiated by different irradiation depth and irradiation time in turn.Both the volume of biological focal region and the distance between the necrosis center and the tissue surface were tested,and the irradiated tissues were pathologically examined.The effects upon the volume of biological focal region by different irradiation depth and irradiation time were also studied.Results Coagulative necrosis took place at the preset position with clear border with nearby normal tissue.By the same radiation dose,there was no notable difference in the volume of biological focal region between two groups（P〉0.05）,nor hotable difference between preset depth and irradiation depth（P〉0.05）.When radiation conditions were all the same,the volume of biological focal region increased as the irradiation time increased,and it decreased as irradiation depth increased.Conclusion The studied machine is able to introduce exact and effective injury in tissue in the rotary radiation mode.The size of biologic focus region is determined by irradiation depth and irradiation time.