Avadhani J S, Pradhan A S, Sankar A, Viswanathan P S
Department of Medical Physics, Tata Memorial Hospital, Bombay, India.
Radiother Oncol. 1995 Oct;37(1):71-3. doi: 10.1016/0167-8140(95)01615-n.
In clinical situations large numbers of rectangular divergent blocks are required at different off-axis positions from central axis to shield sensitive organs. Superiority of divergent blocks over non-divergent blocks on a flat tray lies in improving the dose homogeneity. A method has been developed to minimize the number of divergent shielding blocks by using a concave tray at the collimator. The results of use of a single divergent block are similar to that of the use of several divergent blocks, each to match at different off-axis positions in the radiation beam. This type of single concave tray thus provides a considerable ease of handling divergent blocks in a busy radiotherapy centre.
在临床情况下，需要大量矩形发散挡块在离中心轴不同的离轴位置来屏蔽敏感器官。在平板托盘上，发散挡块相对于非发散挡块的优势在于提高剂量均匀性。已经开发出一种方法，通过在准直器处使用凹形托盘来减少发散屏蔽挡块的数量。使用单个发散挡块的结果与使用几个发散挡块的结果相似，每个发散挡块在辐射束中的不同离轴位置进行匹配。因此，这种类型的单个凹形托盘在繁忙的放射治疗中心提供了相当大的便利，便于处理发散挡块。
