beam type - static, 所有的出束控制點的屬性是不變的
- dynamic,在一個或多個控制點的屬性是可變的,gantry運動中出束
STATIC = All Control Point Sequence (300A,0111) attributes remain unchanged between consecutive pairs of control points with changing Cumulative Meterset Weight (300A,0134). DYNAMIC = One or more Control Point Sequence (300A,0111) attributes change between one or more consecutive pairs of control points with changing Cumulative Meterset Weight (300A,0134).
beam technical - step and shoot,MLC變化到某個形狀,出束,再變化,再出束,不會同時進行。
- sliding window,MLC連續(xù)變化,連續(xù)出束,同時進行。
planning type - 2D, general plan,常規(guī)計劃;
- Conformal,適形計劃;
- IMRT,調(diào)強計劃;
- conformal arc,適形拉弧治療,MLC實行變化
- burst arc,西門子的模式,只能在很小的弧度內(nèi)連續(xù)出束,當MLC移動時是不能出束的,只有當MLC形狀已經(jīng)適形完成,才會在很小的弧度出束
- continuous arc,例如醫(yī)科達的VMAT和瓦里安的Rapid arc,在指定弧度內(nèi)連續(xù)出束,且同時MLC性狀發(fā)生變化。
Burst mode delivery differs from continuous mode delivery, used by Elekta's VMAT (Elekta Ltd, Crawley, UK) and Varian's RapidArc (Varian Medical Systems, Palo Alto, CA, USA) implementations, in that dose is not delivered while MLC leaves are moving. Instead, dose is delivered in bursts over very short arc angles and only after an MLC segment shape has been completely formed and verified by the controller.
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