QA OF TREATMENT DELIVERY BY MEANS OF OVERLAID DIGITIZED SIMULATOR PORT FILMS

“质量保证(QA)的一致性 放射治疗配药是一种连续的 无论是在地方上还是在全国范围内，这都是一种关切。强盗雇佣了经纬仪， 直接在两个模拟器上投影对齐和尺寸信息 预定治疗区域的胶片和所有相应的入口 图像。该项目是覆盖来自数字化模拟器的图像 以及端口胶片、电子门户图像和数字重建 从CT数据中分割图像以确定准确性 和辐射场对准相对于 目标和关键的解剖结构。目前，一种扫描激光器 密度计已被获取。这使得我们可以将两者数字化 模拟器和端口胶片进行比较。数字化仪的软件 还允许我们以特殊格式读取和写入文件 对于我们的门户成像单元是必要的，以便图像可以被利用 通过这种方式。此外，我们还开发了软件来 从任何成像模式获取图像胶片图像并旋转 并对其进行扩展，以便可以立即使用 比较一下。已经开发了其他软件来结合 任意给定患者的CT和MRI图像数据以准确 确定目标卷。目前的研究涉及到 一种多通道外基准系统的研制 提高了图像配准精度。此外，还使用了 替代湿法的商用数字成像荧光粉印版 正在探索射野成像中的胶片乳剂。“

"The quality assurance (QA) of the consistency of radiation treatment delivery with the prescription is a continual concern, locally as well as nationally. The ROB employs graticules, projecting alignment and size information directly on both simulator films of the intended treatment fields and all corresponding portal images. This project is to overlay images from digitized simulator and port films, electronic portal images and digitally reconstructed segmental images from CT data in order to determine the accuracy and repeatability of radiation field alignment with respect to the target and critical anatomical structures. Currently a scanning laser densitometer has been acquired. This permits us to digitize both simulator and port films for comparison. Software for the digitizer also allows us to read and write files in the special formats necessary for our portal imaging unit, so that images can be utilized from this modality. Additionally we have developed software to acquire images film images from any imaging modality and to rotate and scale them so that they can be available for immediate comparison. Additional software has been developed to combine CT and MRI image data of any given patient to accurately determine target volumes. Current research involved the development of a multimodality external fiducial system for improving image registration accuracy. Addiaionally, the use of commercial digital imaging phosphor plates as a substitute for wet film emulsions in portal imaging is being explored."