English
Related papers

Related papers: A Successive LP Approach with C-VaR Type Constrain…

200 papers

We conduct a theoretical study of various solution methods for the adaptive fractionation problem. The two messages of this paper are: (i) dynamic programming (DP) is a useful framework for adaptive radiation therapy, particularly adaptive…

Medical Physics · Physics 2012-02-16 Jagdish Ramakrishnan , David Craft , Thomas Bortfeld , John N. Tsitsiklis

Background: Radiotherapy treatment planning involves solving large-scale optimization problems that are often approximated and solved sub-optimally due to time constraints. Central to these problems is the dose influence matrix which…

Medical Physics · Physics 2024-10-02 Mojtaba Tefagh , Gourav Jhanwar , Masoud Zarepisheh

Today, intensity-modulated radiation therapy (IMRT) is one of the methods used to treat brain tumors. In conventional treatment planning methods, after identifying planning target volume (PTV), and organs at risk (OARs), and determining the…

Quantitative Methods · Quantitative Biology 2023-05-15 Mobina Naeemi , Mohamad Reza Esmaeili , Iraj Abedi

We apply the superiorization methodology to the intensity-modulated radiation therapy (IMRT) treatment planning problem. In superiorization, linear voxel dose inequality constraints are the fundamental modeling tool within which a…

Medical Physics · Physics 2022-07-28 Florian Barkmann , Yair Censor , Niklas Wahl

Interior point methods (IPMs) are a common approach for solving linear programs (LPs) with strong theoretical guarantees and solid empirical performance. The time complexity of these methods is dominated by the cost of solving a linear…

Optimization and Control · Mathematics 2022-02-04 Gregory Dexter , Agniva Chowdhury , Haim Avron , Petros Drineas

We consider continuous-time stochastic optimal control problems featuring Conditional Value-at-Risk (CVaR) in the objective. The major difficulty in these problems arises from time-inconsistency, which prevents us from directly using…

Optimization and Control · Mathematics 2020-05-27 Christopher W. Miller , Insoon Yang

We propose a novel optimization model for volumetric modulated arc therapy (VMAT) planning that directly optimizes deliverable leaf trajectories in the treatment plan optimization problem, and eliminates the need for a separate…

Medical Physics · Physics 2014-03-05 Dávid Papp , Jan Unkelbach

Noncoplanar radiation therapy treatment planning has the potential to improve dosimetric quality as compared to traditional coplanar techniques. Likewise, automated treatment planning algorithms can reduce a planner's active treatment…

Medical Physics · Physics 2022-01-19 Charles Huang , Yong Yang , Lei Xing

A central problem in the field of radiation therapy (RT) is how to optimally deliver dose to a patient in a way that fully accounts for anatomical position changes over time. As current RT is a static process, where beam intensities are…

Medical Physics · Physics 2019-09-04 Rodney D. Wiersma , Xinmin Liu

In multi-stage radiotherapy, a patient is treated in several stages separated by weeks or months. This regimen has been motivated mostly by radiobiological considerations, but also provides an approach to reduce normal tissue dose by…

We consider the effects of parameter uncertainty on the optimal radiation schedule in the context of the linear-quadratic model. Our interest arises from the observation that if inter-patient variations in OAR and tumor sensitivities to…

Tissues and Organs · Quantitative Biology 2015-06-05 Hamidreza Badri , Yoichi Watanabe , Kevin Leder

Stereotactic body radiotherapy (SBRT) is characterized by delivering a high amount of dose in a short period of time. In SBRT the dose is delivered using open fields (e.g., beam's-eye-view) known as "apertures". Mathematical methods can be…

Medical Physics · Physics 2015-06-15 Hamed Yarmand , David Craft

Precision medicine involves developing individualized treatment regimes (ITRs) which allow for treatment decisions to be tailored to patient characteristics. Naturally, the identification of the optimal regime, that is, the rule which…

Methodology · Statistics 2025-09-30 Misha Dolmatov , Erica E. M. Moodie , David A. Stephens , Dipankar Bandyopadhyay

Conventional beam orientation optimization (BOO) algorithms for IMRT assume that the same set of beam angles is used for all treatment fractions. In this paper we present a BOO formulation based on group sparsity that simultaneously…

Medical Physics · Physics 2018-03-14 Daniel O'Connor , Dan Nguyen , Dan Ruan , Victoria Yu , Ke Sheng

Purpose: This study explores the feasibility of dose-escalated proton beam therapy (dPBT) for Locally Advanced Pancreatic Cancer (LAPC) patients by modeling common patient scenarios using current clinically-adopted practices. Methods: Five…

Medical Physics · Physics 2025-07-30 M. A. McIntyre , J. Midson , P. Wilson , P Gorayski , C. E. Hsieh , S. W. Wu , E. Bezak

Delineating and planning with respect to regions suspected to contain microscopic tumor cells is an inherently uncertain task in radiotherapy. The recently proposed \textit{clinical target distribution} (CTD) is an alternative to the…

Medical Physics · Physics 2023-04-26 Ivar Bengtsson , Anders Forsgren , Albin Fredriksson

In many sequential decision-making problems we may want to manage risk by minimizing some measure of variability in costs in addition to minimizing a standard criterion. Conditional value-at-risk (CVaR) is a relatively new risk measure that…

Artificial Intelligence · Computer Science 2014-07-14 Yinlam Chow , Mohammad Ghavamzadeh

A new delivery option for cancer centers equipped with linear accelerators fitted with multi-leaf collimators (MLC) -- i.e. centers which can perform intensity modulated radiation therapy (IMRT) -- is rotational delivery. In rotational…

Medical Physics · Physics 2009-10-27 David Craft , Thomas Bortfeld

Purpose: To demonstrate the feasibility of fast Monte Carlo (MC) based inverse biological planning for the treatment of head and neck tumors in spot-scanning proton therapy. Methods: Recently, a fast and accurate Graphics Processor Unit…

Medical Physics · Physics 2016-10-11 H. Wan Chan Tseung , J. Ma , C. R. Kreofsky , D. Ma , C. Beltran

Individualized treatment rules (ITRs) are considered a promising recipe to deliver better policy interventions. One key ingredient in optimal ITR estimation problems is to estimate the average treatment effect conditional on a subject's…

Methodology · Statistics 2021-03-16 Hongming Pu , Bo Zhang