نتایج جستجو برای: pencil beam

تعداد نتایج: 116960  

2016
A. N. Schreuder S. G. Hedrick J. R. Renegar T. J. Netherton H. Chen M. D. Blakey M. E. Artz B. H. Robison

After many years of development, proton therapy is finally reaching the point of mass adoption in clinical practice. Advances in particle accelerator technology and improved dose delivery techniques have provided strong driving forces for expanded use. Pencil beam scanning (PBS) is the generic name for radiation dose delivery to a target volume using individually controlled small pencil beams o...

Journal: :Strahlentherapie und Onkologie : Organ der Deutschen Rontgengesellschaft ... [et al] 2007
Marius Treutwein Ludwig Bogner

BACKGROUND AND PURPOSE For several years three-dimensional treatment-planning systems have used pencil beam algorithms in the calculation of electron fields. Nowadays, exact Monte Carlo methods are commercially available, showing good correspondence to experimental results. Clinical examples are investigated to find differences in the dose distribution of treatment plans, which are calculated w...

Journal: :journal of biomedical physics and engineering 0
t r verma king george medical university,up;lucknow n k painuly king george medical university, up, lucknow, indiaسازمان اصلی تایید شده: 0 دانشگاه های خارج از کشور s p mishra سازمان اصلی تایید شده: 0 دانشگاه های خارج از کشور m shajahan n singh king george medical university, up, lucknow, india m l b bhatt dr.ram manohar lohia institute of medical sciences, lucknow, indiaسازمان اصلی تایید شده: 0 دانشگاه های خارج از کشور

background: inclusion of inhomogeneity corrections in intensity modulated small fields always makes conformal irradiation of lung tumor very complicated in accurate dose delivery. objective: in the present study, the performance of five algorithms via monte carlo, pencil beam, convolution, fast superposition and superposition were evaluated in lung cancer intensity modulated radiotherapy planni...

Background: Recent studies in eye plaque brachytherapy have shown a considerable difference between the dosimetric results using water phantom and a model of human eye containing realistic materials. In spite of this fact, there is a lack of simulation studies based on such a model in proton therapy literatures. In the presented work, the effect of utilizing an eye model with ocular media on pr...

Journal: :Symposium - International Astronomical Union 2003

Journal: :Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology 2006
Tufve Nyholm Jörgen Olofsson Anders Ahnesjö Mikael Karlsson

BACKGROUND AND PURPOSE New treatment techniques in radiotherapy employ increasing dose calculation complexity in treatment planning. For an adequate check of the results coming from a modern treatment planning system, clinical tools with almost the same degree of generality and accuracy as the planning system itself are needed. To fulfil this need we propose a photon pencil kernel parameterizat...

Journal: :Physics in medicine and biology 2012
Benjamin Clasie Nicolas Depauw Maurice Fransen Carles Gomà Hamid Reza Panahandeh Joao Seco Jacob B Flanz Hanne M Kooy

Proton, as well as other ion, beams applied by electro-magnetic deflection in pencil-beam scanning (PBS) are minimally perturbed and thus can be quantified a priori by their fundamental interactions in a medium. This a priori quantification permits an optimal reduction of characterizing measurements on a particular PBS delivery system. The combination of a priori quantification and measurements...

Journal: :The Astrophysical Journal 1994

Journal: :Monthly Notices of the Royal Astronomical Society 2001

Journal: :SIAM Journal on Mathematical Analysis 2020

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