In this research work, a simple homemade cubic phantom was designed to validate the Image-Guided Radiotherapy (IGRT) set up and verified with the help of tungsten fiducial markers (size 2–3 mm) inserted into the cubic phantom. Phantom made up of Styrofoam, was scanned with the help of 16 slice Toshiba CT scanner where each slice was of 1 mm thickness and HU level set to −1000. A radio-opaque contrast medium was rubbed on the phantom to visualize the scanner images. Once the iso-center had been marked on a phantom with the help of in-room positioning laser and the fields (RT-LAT and AP) were applied on the contoured body of the phantom in Varian’s ARIA-11 Eclipse dosimeter software, the same position of the phantom was reproduced on Varian’s Linear Accelerator DHX. Known shifts of 3.0 to 30.0 mm from the marked iso-center were applied on the phantom by moving the couch in all six directions one by one. On each applied couch shift, an x-ray image of the phantom was acquired with the help of an MV portal imager of Linac in AP and RT-LAT direction. This image was superimposed with a reference image of phantom and shift accuracy calculated by ARIA-11 software was noted down. It turned out that irrespective of the position of the phantom on the couch, the calculated corrected shift and deviation from reference position was always between1–2 mm which is the required accuracy for IGRT according to International Atomic Energy Agency (IAEA). This process was repeated 40 times and each time, the corrected shift came out to be1–2 mm. We can conclude that our system is safe and accurate enough to perfectly position the actual patient for IGRT.

在这项研究工作中，设计了一个简单的自制立方体模型来验证图像引导放射治疗 (IGRT) 的设置，并在插入立方体模型的钨基准标记（尺寸 2-3 毫米）的帮助下进行验证。由聚苯乙烯泡沫塑料制成的模型在 16 片东芝 CT 扫描仪的帮助下进行扫描，其中每片厚度为 1 毫米，HU 水平设置为 -1000。在体模上涂抹不透射线的造影剂以显示扫描仪图像。一旦在室内定位激光的帮助下在体模上标记了等中心，并且在 Varian 的 ARIA-11 Eclipse 剂量计软件中将场（RT-LAT 和 AP）应用到体模的轮廓体上，同样的体模的位置在瓦里安的直线加速器 DHX 上再现。已知的 3.0 到 30 的班次。通过在所有六个方向上一一移动沙发，将距离标记的等中心 0 mm 应用到体模上。在每次应用沙发移位时，在 AP 和 RT-LAT 方向的直线加速器 MV 门户成像仪的帮助下，获取了体模的 X 射线图像。该图像与模型的参考图像叠加，并记下由 ARIA-11 软件计算的移位精度。结果表明，无论模型在沙发上的位置如何，计算出的校正偏移和与参考位置的偏差始终在 1-2 毫米之间，这是国际原子能机构 (IAEA) 要求的 IGRT 精度。这个过程重复了 40 次，每次校正的偏移量为 1-2 毫米。我们可以得出结论，我们的系统足够安全和​​准确，可以完美地定位实际患者进行 IGRT。