This is a recent technique where the field shape conforms three dimensionally to the tumor. Multiple 2 0r 3mm CT sections are taken. Images are transferred to the 3D treatment planning system.
The planning target volume (PTV) is marked in every CT section. The critical structures in each section are outlined.
The beams are positioned. Multileaf collimation is done to get a field conforming to the target volume sparing the normal tissues.
Dose prescription and computation is done. Plan evaluation by a Dose Volume Histogram (DVH) is mandatory.
Optimization is a systematic computerized process that generates a large number of plans rapidly, to finalize the optimal plan.
Quality assurance is the crucial step in all modern radiotherapy modalities.
The dose deliver is confirmed with acrylic phantoms to be doubly sure that the treatment is accurate