Evidence map›Paper›PMID 40657672›Full record

ArticleJournal of applied clinical medical physics2025

Feasibility of a normoxic N-vinylpyrrolidone-based polymer gel (VIPET) dosimeter for three-dimensional proton beam measurements.

Ai Nakaoka, Kenji Hotta, Taeko Matsuura, Yoshihiko Hoshino, Hidenobu Tachibana

Abstract read
In one paragraph

Article in Journal of applied clinical medical physics, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing 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

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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

1 citing paper in PubMed.

  1. 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

5 authors.

Ai NakaokaRadiation Safety and Quality Assurance Division, National Cancer Center Hospital East, Chiba, Japan.
Kenji HottaRadiation Safety and Quality Assurance Division, National Cancer Center Hospital East, Chiba, Japan.
Taeko MatsuuraDivision of Applied Quantum Science and Engineering Faculty of Engineering, Hokkaido University, Hokkaido, Japan.
Yoshihiko HoshinoDepartment of Radiology, Gunma University Hospital, Gunma, Japan.
Hidenobu TachibanaRadiation Safety and Quality Assurance Division, National Cancer Center Hospital East, Chiba, Japan.

Funding

JSPS KAKENHI JP 24K22101JST FOREST Program JPMJFR200X
6 · The paper itself

Abstract

backgroundGel dosimeters enable three-dimensional dose measurement in x-ray and charged-particle therapies. A normoxic N-vinylpyrrolidone-based polymer gel (VIPET) dosimeter is expected to provide high-precision proton dose measurements. However, reports on the fundamental performance of VIPET gel dosimeters in proton beam measurement are limited, and the accuracy of position and dose measurements still needs to be determined. PURPOSE: We evaluated the accuracy of the VIPET gel dosimeter in proton beam measurement.

methodsProton beams of 190 MeV were delivered at dose rates of 2 and 8 Gy/min, and N-vinylpyrrolidone-based polymer gel dosimeters containing an inorganic salt as a sensitizer (iVIPET) were irradiated with a 10 × 10 cm

resultsA strong linear relationship was observed in the 0-30 Gy range. Dose uncertainties were in the range 1%-3%. Three sets of percentage depth dose measurements showed good agreement within 1.6%. Energy (LET) dependence led to measured peak doses being 23% lower than the treatment planning system (TPS) calculations. Proton energy effects in the plateau region were limited and dose rate effects were not recognized. Beam profiles in the axes parallel and perpendicular to the beam axis showed variations of approximately 1.2% and 1.3%, respectively, compared with the TPS calculations. The SPR was consistent with the TPS derived from CT values (1.03).

conclusionsThe VIPET dosimeter showed high reproducibility and uniformity in range and dose measurements of proton therapy beams without energy dependency in the plateau region or dose rate dependency in 2-8 Gy/min. The dosimeter also showed energy (LET) dependence comparable with that reported in previous studies.

Indexed as

Phantoms, ImagingPolymersProton TherapyPyrrolidinonesRadiation DosimetersRadiometryRadiotherapy Planning, Computer-AssistedFeasibility StudiesGelsHumansLinear Energy TransferRadiotherapy DosageRadiotherapy, Intensity-ModulatedGelsN-vinyl-2-pyrrolidinonePolymersPyrrolidinonespolymer gel dosimeterproton beamVIPET

Identifiers

PMID40657672
PMCPMC12257340

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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.