RTS-200S放疗二维自动扫描测量水箱的研制

目的 本研究组在参考国外先进技术的基础上历时5年研制成功了先进的放疗剂量自动化检测大型仪器。该机适用于医院放疗科和省级放射卫生检测机构对放疗设备的验收检测。对于放疗计划系统需要的大量临床物理参数可以实现快速测量。方法 采用2个电离室为扫描探头和检测探头，利用最新的自动化测量和控制技术，可以快速方便和准确地扫描测量各种型号医用直线加速器、X刀和60Co远距离治疗机的射线束参数。通过计算机控制多细分步进电机驱动精密机械传动系统，使该系统的扫描定位精度小于0．1mm；实现对放疗射线束的水平和垂直方向的扫描，对放射治疗射野的离轴比和百分深度等参数实现快速的测量。结果RTS-200放疗二维自动扫描水箱系统扫描测量的加速器x射线的Profide和PDD测量曲线比较平滑，对X射线的均整度，对称性等数据的分析结果与Varian公司的测量结果吻合；从测量PDD曲线可以看出，15MV的测量的D10／Dmax的分析值与Varian公司的测量标称值接近。结论 RTS-200S放疗二维自动扫描测量水箱的性能完全可以满足测量医用加速器的射线束特性的需要。

Development of RTS-200S 2D automatic scanning dose measuring water phantom for radiotherapy

Objective To developt a 2D automatic scanning water phantom, being applicable for acceptance tests of radiotherapy equipment and quick measurements of clinical physical parameters for radiotherapy beams and suitable for use in radiotherapy departments and provincial monitoring institutions. Methods Two chambers were used as a scanning detector and a beam monitor, respectively.Modern automatic techniques were adopted in the scanning system so as to realize rapid and accurate measurement for medical linear accelerator, X-knife and Co-60 therapy beams.The precision of scanning position was less than±0. 1 mm by means of computer-controlled stepper motors. Results RTS-200S enabled user to acquire data of beam profiles, depth dose curve.RTP software program integrated data collec`tion, analysis, output and storage.The measuring results were in agreement with those measured by Varian company. Conclusion The RTS-200S water phantom and electronic control are excellent in both accuracy and reliability for measuring beam speciality of radiotherapy units.