Mini and Micro Multileaf Collimators
نویسندگان
چکیده
Multiple arc or multiple field convergent beam irradiation techniques have been used extensively for stereotactic radiosurgery (SRS) or radiotherapy (SRT) of small lesions. A major problem is that dose distributions produced by employing rectangular or circular collimators are of simple convex shape and therefore do not allow conformal treatment of irregularly shaped lesions. The use of multiple overlapping spherical treatments results in some field shaping advantages and permits the treatment of larger tumors. Disadvantages of this multiple isocenter technique include the increased treatment time and the substantial dose inhomogeneity that is the result of overlap of multiple fields. This dose inhomogeneity correlates significantly with side-effects and increased morbidity for those patients, as has been shown by Nedzi et al. [10]. Improved tumor dose homogeneity can be accomplished by using a field shaping device, which can form the optimal field shape for each beam direction.
منابع مشابه
Beam characteristic of P.E collimators Add-on multileaf collimator
Introduction: Multileaf collimators (MLCs) are computer-controlled devices which are Useful and cost-effective tools for conformal therapy and intensity modulation radiotherapy (IMRT). Nowadays MLCs are important and standard configuration of the new medical linear accelerators which are substitute of conventional Blocks and has eliminated the ...
متن کاملA New Sequential Extraction Heuristic for Optimizing the Delivery of Cancer Radiation Treatment Using Multileaf Collimators
delivery of cancer radiation treatment using multileaf collimators Davaasteren Baatar, Natashia Boland, Robert Johnston Department of Mathematics and Statistics, The University of Melbourne, Victoria 3010, Australia, {[email protected], [email protected], , [email protected]} Horst W. Hamacher Department of Mathematics, University of Kaiserslautern, 67653 Kaiserslautern, Germany,...
متن کاملValidation of calculations for electrons modulated with conventional photon multileaf collimators.
Treating shallow tumors with a homogeneous dose while simultaneously minimizing the dose to distal critical organs remains a challenge in radiotherapy. One promising approach is modulated electron radiotherapy (MERT). Due to the scattering properties of electron beams, the commercially provided secondary and tertiary photon collimation systems are not conducive for electron beam delivery when s...
متن کاملOptimal Sequencing of Dynamic Multileaf Collimators
Dynamic multileaf collimator (DMLC)-intensity modulated radiation therapy (IMRT) is used to delivery intensity-modulated beams using an MLC, with the leaves in motion. DMLC-IMRT requires the conversion of a radiation fluence map into a leaf sequence file that controls the movement of the MLC while the beam is on. It is imperative that the fluence map delivered using the leaf sequence file be as...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 1999