Learn More
The optimization of intensity distributions and the delivery of intensity-modulated treatments with dynamic multi-leaf collimators (MLC) offer important improvements to three-dimensional conformal radiotherapy. In this study, a nine-beam intensity-modulated prostate plan was generated using the inverse radiotherapy technique. The resulting fluence profiles(More)
The fundamental question of how many equispaced coplanar intensity-modulated photon beams are required to obtain an optimum treatment plan is investigated in a dose escalation study for a typical prostate tumor. Furthermore, optimization of beam orientations to improve dose distributions is explored. A dose-based objective function and a fast gradient(More)
PURPOSE To improve the local control of patients with adenocarcinoma of the prostate we have implemented intensity modulated radiation therapy (IMRT) to deliver a prescribed dose of 81 Gy. This method is based on inverse planning and the use of dynamic multileaf collimators (DMLC). Because IMRT is a new modality, a major emphasis was on the quality(More)
The application of a multiple fixed field technique employing individually shaped and intensity-modulated beams makes it possible to produce dose distributions of high conformity even in the case of concave target volumes. With the technique presented here arbitrary intensity-modulated beams for the practical solution of the inverse problem can be(More)
PURPOSE/OBJECTIVE For complex planning situations where organs at risk (OAR) surrounding the target volume place stringent constraints, intensity-modulated treatments with photons provide a promising solution to improve tumor control and/or reduce side effects. One approach for the clinical implementation of intensity-modulated treatments is the use of a(More)
When intensity-modulated fields are created using a multileaf collimator with dynamic leaf movement the potential problem for underdosage beneath the tongue-and-groove interleaf regions has been identified and a solution based on leaf-movement synchronization has been provided by Van Santvoort and Heijmen. Their first-order analysis ignored the transmission(More)
Substantial improvement in conformal radiotherapy is possible using modulated irradiation fields. Such modulated fields may be generated even with conventional accelerators by means of individual metal compensators or with the recently available dynamic multileaf collimators (MLC). For treatment planning a new kind of planning program is required that can(More)
Intensity modulation provides greatly increased control, leading to superior dose distributions with a potential for improved clinical outcome. It also allows us to compensate for deviations from the expected patterns in dose distributions caused by the lateral transport of radiation. This is important not only to produce more homogeneous dose distributions(More)