All inverse planning involves weight optimization. Beamlet-based Inverse Planning (BBIP) irradiates complex target volumes with a large number of small beams. The number of small beams or beamlets is often more than one thousand. The optimization process adjusts the weights of these beams to produce a desired dose distribution. Delivery of this large number of small beams is challenging, but ma...

PURPOSE To develop a real-time target position estimation method using stereoscopic kilovoltage (kV)/megavoltage (MV) imaging and external respiratory monitoring, and to investigate the performance of a dynamic multileaf collimator tracking system using this method. METHODS AND MATERIALS The real-time three-dimensional internal target position estimation was established by creating a time-var...

PURPOSE To perform a quantitative study to verify that the mechanical field center coincides with the radiation field center when both are off from the isocenter during the single-isocenter technique in linear accelerator-based SRS/SBRT procedure to treat multiple lesions. METHODS We developed an innovative method to measure this accuracy, called the off-isocenter Winston-Lutz test, and here ...

Shape matrix decomposition is a subproblem in radiation therapy planning. A given fluence matrix A has to be decomposed into a sum of shape matrices corresponding to homogeneous fields that can be shaped by a multileaf collimator (MLC). We solve the problem of minimizing the delivery time for an approximation of A satisfying certain prescribed bounds, under the additional condition that the use...