Evidence map›Paper›PMID 41477292›Full record

ArticlePrecision radiation oncology2025

Experimental design and control methods for dose rate optimization in a synchrotron-based proton therapy beamline.

Jason Tang, Daniel Liu, Jacob Mathew, Sabrina Campelo, Lawrence Bronk, Paige Taylor, Yuting Li, Fada Guan

Abstract read
In one paragraph

Article in Precision radiation oncology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

  1. Article
  2. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Jason TangDepartment of Radiation Physics The University of Texas MD Anderson Cancer Center Houston USA.
Daniel LiuDepartment of Radiation Physics The University of Texas MD Anderson Cancer Center Houston USA.
Jacob MathewDepartment of Radiation Physics The University of Texas MD Anderson Cancer Center Houston USA.
Sabrina CampeloDepartment of Radiation Physics The University of Texas MD Anderson Cancer Center Houston USA.
Lawrence BronkDepartment of Radiation Physics The University of Texas MD Anderson Cancer Center Houston USA.
Paige TaylorDepartment of Radiation Physics The University of Texas MD Anderson Cancer Center Houston USA.
Yuting LiDepartment of Radiation Physics The University of Texas MD Anderson Cancer Center Houston USA.
Fada GuanDepartment of Radiation Physics The University of Texas MD Anderson Cancer Center Houston USA.

Funding

Tumor Evolution and Metastasis ProgramP30CA016672 · NCI · UNIVERSITY OF TX MD ANDERSON CAN CTR · PI DIANE BODURKA · 1985 to 2026
$290.8M
NCI NIH HHS P30 CA016672
6 · The paper itself

Abstract

Background: Ultra-high dose rate radiotherapy (typically defined >40 Gy/s) has shown promise for enhanced normal tissue sparing while maintaining tumor control, termed the FLASH effect when this biological response is observed. However, precise dose rate control remains a technical challenge in proton therapy systems, particularly for research applications investigating dose rate effects. Purpose: To develop and validate a passive beam modulation technique using tungsten scatterers for controllable dose rate adjustment in a synchrotron-based proton therapy beamline without modifying accelerator parameters. Methods: We investigated dose rate modulation using tungsten foils of varying thicknesses (0.1-3.5 mm) positioned upstream in an 87.2 MeV experimental proton beamline. Monte Carlo simulations using Geant4 were performed to model the dose rate variation as a function of the tungsten scatter's thickness. Experimental validation was conducted using an Advanced Markus ionization chamber for dose rate measurements and EBT-XD radiochromic films for lateral dose profile analysis. Five tungsten thicknesses were tested with full-spill deliveries (∼1400 monitor units (MUs), and ∼100 milliseconds (ms) pulse width). Results: An inverse exponential relationship between dose rate and scatterer thickness was observed, with measured dose rates ranging from 288.9±0.7 Gy/s (0.1 mm tungsten) to 10.2±0.2 Gy/s (3.5 mm tungsten). Experimental measurements validated the accuracy of Monte Carlo predictions at the standard condition (1400 MU delivered in 100 ms) by falling within the 95% confidence intervals. Lateral beam profiles demonstrated progressive broadening with increased scatterer thickness, and the film measurements showed good agreements with Monte Carlo simulation (<2% difference at beam center). Conclusions: Tungsten scatterer thickness modulation provides a practical, controllable method for dose rate adjustment spanning conventional to FLASH regimes. This passive approach enables precise dose rate control for preclinical radiobiological research without requiring modifications of accelerator structure and parameters.

Indexed as

dose rateFLASH radiotherapyMonte Carlo simulationproton therapyradiochromic filmsynchrotrontungsten foil

Identifiers

PMID41477292
PMCPMC12750309

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.