Smoothing intensity-modulated treatment delivery under hardware constraints
- 3 December 2002
- journal article
- Published by Wiley in Medical Physics
- Vol. 29 (12), 2937-2945
- https://doi.org/10.1118/1.1521121
Abstract
A method is developed to smooth intensity-modulated beam delivery while considering hardware constraints. The method uses matrix algebra to model MLC leaf motion and hardware constraints such as interleaf digitization, synchronization requirements, and intersegment field abutment to deliver intensity modulated beam sequences. It was implemented and demonstrated for simulated and clinical intensity modulated cases. The simulated cases included intensity distributions from 3 x 3 to 30 x 30 in dimension with 1,000 intensity levels. The clinical examples included four treatments sites: prostate, head and neck, lung, and esophagus cancers. In particular, we studied the relationships between the intensity levels, segment numbers and their influence on the dose-volume histograms of the inversely optimized IMRT treatment plans. It was found that a significant reduction in the leaf segment numbers was achieved by applying the smoothing approach. The effects were found to be more significant for the unconstrained delivery than for the constrained delivery. The effects were also found to be more sensitive for the complex intensity distributions such as the head-and-neck cases than for the less complex ones such as the prostate cases. These results demonstrated the feasibility of maintaining inversely optimized treatment plans under acceptable tolerance levels while smoothing IMRT treatments with hardware constraints.Keywords
This publication has 14 references indexed in Scilit:
- Depth dose enhancement of electron beams subject to external uniform longitudinal magnetic fields: A Monte Carlo studyMedical Physics, 2002
- Implementing multiple static field delivery for intensity modulated beamsMedical Physics, 2001
- Minimizing the number of segments in a delivery sequence for intensity‐modulated radiation therapy with a multileaf collimatorMedical Physics, 2001
- Smoothing intensity-modulated beam profiles to improve the efficiency of deliveryMedical Physics, 2001
- Hardware-sensitive optimization for intensity modulated radiotherapyPhysics in Medicine & Biology, 2000
- Comparison of algorithms for multileaf collimator field segmentationMedical Physics, 1999
- Minimizing static intensity modulation delivery time using an intensity solid paradigmInternational Journal of Radiation Oncology*Biology*Physics, 1999
- An optimized leaf-setting algorithm for beam intensity modulation using dynamic multileaf collimatorsPhysics in Medicine & Biology, 1998
- Dynamic multileaf collimation without `tongue-and-groove' underdosage effectsPhysics in Medicine & Biology, 1996
- Realization and verification of three-dimensional conformal radiotherapy with modulated fieldsInternational Journal of Radiation Oncology*Biology*Physics, 1994