BACKGROUND Intensity-modulated radiation therapy (IMRT) uses solid compensators or multileaf collimators to modulate the intensity of radiation in each field, delivering highly conformal dose distributions. This technique allows treating volumes with concave shapes when the target is close to a critical structure. The movement of multileaf collimator under computer control can modulate the dose...

Radiation therapy is subject to uncertainties that need to be accounted for when determining a suitable treatment plan for a cancer patient. For lung and liver tumors, the presence of breathing motion during treatment is a challenge to the effective and reliable delivery of the radiation. In this paper, we build a model of motion uncertainty using probability density functions that describe bre...

In intensity-modulated radiation therapy (IMRT) not only is the shape of the beam controlled, but combinations of open and closed multileaf collimators modulate the intensity as well. In this paper, we offer a mixed integer programming approach which allows optimization over beamlet fluence weights as well as beam and couch angles. Computational strategies, including a constraint and column gen...

3 Sammanfattning (Swedish) 4 Original papers 5 Abbreviations 6

When Policy Topic is covered Intensity-modulated radiation therapy (IMRT) may be considered medically necessary as a technique to deliver whole breast irradiation in patients receiving treatment for left-sided breast cancer after breast-conserving surgery when all the following conditions have been met:  Significant cardiac radiation exposure cannot be avoided using alternative radiation techn...

Three-dimensional (3D) image-based treatment planning and new delivery technologies have spurred the implementation of external beam radiation therapy techniques, in which the high-dose region is conformed much more closely to the target volume than previously possible, thus reducing the volume of normal tissues receiving a high dose. This form of external beam irradiation is referred to as 3D ...

PURPOSE To investigate the role of beam orientation optimization in intensity-modulated radiation therapy (IMRT) and to examine the potential benefits of noncoplanar intensity-modulated beams. METHODS AND MATERIALS A beam orientation optimization algorithm was implemented. For this purpose, system variables were divided into two groups: beam position (gantry and table angles) and beam profile...