Basic research of high-voltage X-ray CT converging radiotherapy

在这笔资金的帮助下，我们完成了一个人体胸部模型，它是基于M.Crysty设计的椭球形状的数字模型。该模型类似于人类男性胸部的简化模型，包括肺实质，其中包含一个直径为2厘米的球形肿瘤(GTV)。用EGS4程序进行了蒙特卡罗模拟，并对模拟结果进行了分析。较低能量的X射线辐照表明，无论是在入射方向还是在垂直入射方向，都表现出良好的平坦度。另一方面，由于体模胸部密度不均匀，2002年，我们改装了一台螺旋CT扫描仪用于诊断。该CT设备已安装在我们部门的实验目的，目的是为了供应商的合作工作。使用微室和钻石探测器进行实际的基本剂量测定。还进行了胶片测量等。还模拟了呼吸运动，并进行了动物研究。下一步的项目，包括计算机模拟和剂量计算，目前正在进行研究。

Helped by the grant, we have completed a human chest phantom, which is based on a ellipsoid-shaped numerical phantom designed by M.Crysty. The phantom resembles a simplified model of human male chest and includes lung parenchyma in which a spherical tumor (GTV) of 2 cm diameter is included.A narrow beam of X-ray collimated to 3cm in diameter, was used to irradiate the phantom. A Monte-Carlo simulation was performed with EGS4 code and the result was analyzed. Lower energy X-ray irradiation indicated good flatness both in the direction of the beam incidence and perpendicular to it. On the other hand, due to the inhomogeneous density in the phantom chest,In 2002, we modified a helical CT scanner for diagnostic purpose. The CT device had been installed for experimental purposes at our department for the aim of a corporative work of the vender. Actual basic dosimetories were performed using micro-chamber and a diamond detector. Film measurements etc.were also performed. Respiration movements were also simulated and animal studies were carried out. Next step project that includes computer simulations and dose calculations, are now on-going study.