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A fast and robust constraint-based online re-optimization approach for automated online adaptive intensity modulated proton therapy in head and neck cancer

Oud, Michelle (author), Breedveld, Sebastiaan (author), Rojo-Santiago, Jesús (author), Giżyńska, Marta Krystyna (author), Kroesen, Michiel (author), Habraken, S.J.M. (author), Perko, Z. (author), Heijmen, Ben (author), Hoogeman, M.S. (author)

Objective. In head-and-neck cancer intensity modulated proton therapy, adaptive radiotherapy is currently restricted to offline re-planning, mitigating the effect of slow changes in patient anatomies. Daily online adaptations can potentially improve dosimetry. Here, a new, fully automated online re-optimization strategy is presented. In a...

journal article 2024

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PTV-based VMAT vs. robust IMPT for head-and-neck cancer: A probabilistic uncertainty analysis of clinical plan evaluation with the Dutch model-based selection

Rojo-Santiago, Jesús (author), Korevaar, Erik (author), Perko, Z. (author), Both, Stefan (author), Habraken, S.J.M. (author), Hoogeman, M.S. (author)

Background and purpose: In the Netherlands, head-and-neck cancer (HNC) patients are referred for proton therapy (PT) through model-based selection (MBS). However, treatment errors may compromise adequate CTV dose. Our aims are: (i) to derive probabilistic plan evaluation metrics on the CTV consistent with clinical metrics; (ii) to evaluate...

journal article 2023

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Robustness analysis of CTV and OAR dose in clinical PBS-PT of neuro-oncological tumors: prescription-dose calibration and inter-patient variation with the Dutch proton robustness evaluation protocol

Rojo-Santiago, Jesús (author), Habraken, S.J.M. (author), Romero, Alejandra Méndez (author), Lathouwers, D. (author), Wang, Yibing (author), Perko, Z. (author), Hoogeman, M.S. (author)

Objective. The Dutch proton robustness evaluation protocol prescribes the dose of the clinical target volume (CTV) to the voxel-wise minimum (VWmin) dose of 28 scenarios. This results in a consistent but conservative near-minimum CTV dose (D98%,CTV). In this study, we analyzed (i) the correlation between VWmin/voxel-wise maximum (VWmax)...

journal article 2023

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Sub-second photon dose prediction via transformer neural networks

Pastor Serrano, O. (author), Dong, Peng (author), Huang, Charles (author), Xing, Lei (author), Perko, Z. (author)

Background: Fast dose calculation is critical for online and real-time adaptive therapy workflows. While modern physics-based dose algorithms must compromise accuracy to achieve low computation times, deep learning models can potentially perform dose prediction tasks with both high fidelity and speed. Purpose: We present a deep learning...

journal article 2023

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A Deterministic Adjoint-Based Semi-Analytical Algorithm for Fast Response Change Computations in Proton Therapy

Burlacu, T. (author), Lathouwers, D. (author), Perko, Z. (author)

In this paper we propose a solution to the need for a fast particle transport algorithm in Online Adaptive Proton Therapy capable of cheaply, but accurately computing the changes in patient dose metrics as a result of changes in the system parameters. We obtain the proton phase-space density through the product of the numerical solution to...

journal article 2023

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A probabilistic deep learning model of inter-fraction anatomical variations in radiotherapy

Pastor Serrano, O. (author), Habraken, S.J.M. (author), Hoogeman, M.S. (author), Lathouwers, D. (author), Schaart, D.R. (author), Nomura, Yusuke (author), Xing, Lei (author), Perko, Z. (author)

Objective. In radiotherapy, the internal movement of organs between treatment sessions causes errors in the final radiation dose delivery. To assess the need for adaptation, motion models can be used to simulate dominant motion patterns and assess anatomical robustness before delivery. Traditionally, such models are based on principal...

journal article 2023

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Millisecond speed deep learning based proton dose calculation with Monte Carlo accuracy

Pastor Serrano, O. (author), Perko, Z. (author)

Objective. Next generation online and real-time adaptive radiotherapy workflows require precise particle transport simulations in sub-second times, which is unfeasible with current analytical pencil beam algorithms (PBA) or Monte Carlo (MC) methods. We present a deep learning based millisecond speed dose calculation algorithm (DoTA)...

journal article 2022

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An online adaptive plan library approach for intensity modulated proton therapy for head and neck cancer

Oud, Michelle (author), Breedveld, Sebastiaan (author), Giżyńska, Marta (author), Kroesen, Michiel (author), Hutschemaekers, Stefan (author), Habraken, S.J.M. (author), Petit, Steven (author), Perko, Z. (author), Heijmen, Ben (author), Hoogeman, M.S. (author)

Background and purpose: In intensity modulated proton therapy (IMPT), the impact of setup errors and anatomical changes is commonly mitigated by robust optimization with population-based setup robustness (SR) settings and offline replanning. In this study we propose and evaluate an alternative approach based on daily plan selection from...

journal article 2022

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A fully adaptive nonintrusive reduced-order modelling approach for parametrized time-dependent problems

Alsayyari, F.S. (author), Perko, Z. (author), Tiberga, M. (author), Kloosterman, J.L. (author), Lathouwers, D. (author)

We present an approach to build a reduced-order model for nonlinear, time-dependent, parametrized partial differential equations in a nonintrusive manner. The approach is based on combining proper orthogonal decomposition (POD) with a Smolyak hierarchical interpolation model for the POD coefficients. The sampling of the high-fidelity model to...

journal article 2021

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Accurate assessment of a Dutch practical robustness evaluation protocol in clinical PT with pencil beam scanning for neurological tumors

Rojo-Santiago, Jesús (author), Habraken, S.J.M. (author), Lathouwers, D. (author), Méndez Romero, Alejandra (author), Perko, Z. (author), Hoogeman, M.S. (author)

Background and purpose: Scenario-based robust optimization and evaluation are commonly used in proton therapy (PT) with pencil beam scanning (PBS) to ensure adequate dose to the clinical target volume (CTV). However, a statistically accurate assessment of the clinical application of this approach is lacking. In this study, we assess target...

journal article 2021

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A semi-supervised autoencoder framework for joint generation and classification of breathing

Pastor Serrano, O. (author), Lathouwers, D. (author), Perko, Z. (author)

Background and objective: One of the main problems with biomedical signals is the limited amount of patient-specific data and the significant amount of time needed to record the sufficient number of samples needed for diagnostic and treatment purposes. In this study, we present a framework to simultaneously generate and classify biomedical...

journal article 2021

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How should we model and evaluate breathing interplay effects in IMPT?

Pastor Serrano, O. (author), Habraken, S.J.M. (author), Lathouwers, D. (author), Hoogeman, M.S. (author), Schaart, D.R. (author), Perko, Z. (author)

Breathing interplay effects in Intensity Modulated Proton Therapy (IMPT) arise from the interaction between target motion and the scanning beam. Assessing the detrimental effect of interplay and the clinical robustness of several mitigation techniques requires statistical evaluation procedures that take into account the variability of...

journal article 2021

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Preliminary uncertainty and sensitivity analysis of the Molten Salt Fast Reactor steady-state using a Polynomial Chaos Expansion method

Santanoceto, M. (author), Tiberga, M. (author), Perko, Z. (author), Dulla, Sandra (author), Lathouwers, D. (author)

In this work, we present the results of a preliminary uncertainty quantification and sensitivity analysis study of the Molten Salt Fast Reactor (MSFR) behavior at steady-state performed by applying a non-intrusive Polynomial Chaos Expansion (PCE) approach. An in-house high-fidelity multi-physics simulation tool is used as reactor reference...

journal article 2021

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Technical Note: Investigating interplay effects in pencil beam scanning proton therapy with a 4D XCAT phantom within the RayStation treatment planning system

den Boer, E. (author), Wulff, Jörg (author), Mäder, UIf (author), Engwall, Erik (author), Bäumer, Christian (author), Perko, Z. (author), Timmermann, Beate (author)

Purpose: Pencil beam scanning (PBS) for moving targets is known to be impacted by interplay effects. Four-dimensional computed tomography (4DCT)-based motion evaluation is crucial for understanding interplay and developing mitigation strategies. Availability of high-quality 4DCTs with variable breathing traces is limited. Purpose of this work...

journal article 2021

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Analysis of the Molten Salt Fast Reactor using reduced-order models

Alsayyari, F.S. (author), Tiberga, M. (author), Perko, Z. (author), Kloosterman, J.L. (author), Lathouwers, D. (author)

In this paper, we present a reduced-order modeling approach to study the Molten Salt Fast Reactor (MSFR). Our approach is nonintrusive and based on the proper orthogonal decomposition method. We include adaptivity in selecting the sampling points both in time and parameter space. Steady-state and transient analysis were both performed using...

journal article 2021

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Uncertainty quantification in steady state simulations of a molten salt system using polynomial chaos expansion analysis

Santanoceto, M. (author), Tiberga, M. (author), Perko, Z. (author), Dulla, Sandra (author), Lathouwers, D. (author)

Uncertainty Quantification (UQ) of numerical simulations is highly relevant in the study and design of complex systems. Among the various approaches available, Polynomial Chaos Expansion (PCE) analysis has recently attracted great interest. It belongs to non-intrusive spectral projection methods and consists of constructing system responses...

conference paper 2020

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Addressing Ambiguities in Constrained Sensitivity Analysis for Reactor Physics Problems

Seo, Jeongwon (author), Abdel-Khalik, Hany (author), Perko, Z. (author)

This paper presents an algorithm for completing sensitivity analysis that respects linear constraints placed on the associated model’s input parameters. Any sensitivity analysis (linear or nonlinear, local or global) focuses on measuring the impact of input parameter variations on model responses of interest, which may require the analyst to...

journal article 2020

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Influence of Micro-Pore Connectivity and Micro-Fractures on Calcium Leaching of Cement Pastes: A Coupled Simulation Approach

Perko, Janez (author), Ukrainczyk, Neven (author), Šavija, B. (author), Phung, Quoc Tri (author), Koenders, Eddie A. B. (author)

A coupled numerical approach is used to evaluate the influence of pore connectivity and microcracks on leaching kinetics in fully saturated cement paste. The unique advantage of the numerical model is the ability to construct and evaluate a material with controlled properties, which is very difficult under experimental conditions. Our analysis...

journal article 2020

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Fast and fully-automated multi-criterial treatment planning for adaptive HDR brachytherapy for locally advanced cervical cancer

Oud, Michelle (author), Kolkman-Deurloo, Inger Karine (author), Mens, J.W. (author), Lathouwers, D. (author), Perko, Z. (author), Heijmen, Ben (author), Breedveld, Sebastiaan (author)

Purpose: To develop and evaluate a fast, automated multi-criterial treatment planning approach for adaptive high-dose-rate (HDR) intracavitary + interstitial brachytherapy (BT) for locally advanced cervical cancer. Methods and materials: Twenty-two previously delivered single fraction MRI-based HDR treatment plans (SF_clin) were...

journal article 2020

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A nonintrusive adaptive reduced order modeling approach for a molten salt reactor system

Alsayyari, F.S. (author), Tiberga, M. (author), Perko, Z. (author), Lathouwers, D. (author), Kloosterman, J.L. (author)

We use a novel nonintrusive adaptive Reduced Order Modeling method to build a reduced model for a molten salt reactor system. Our approach is based on Proper Orthogonal Decomposition combined with locally adaptive sparse grids. Our reduced model captures the effect of 27 model parameters on k_eff of the system and the spatial...

journal article 2020