ArticleJournal of applied clinical medical physics2026
A practical framework for routine verification of Spot Position Monitor coordinate consistency in scanned carbon-ion radiotherapy.
Article in Journal of applied clinical medical physics, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
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.
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.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundLog file-based patient specific quality assurance (PSQA) in scanned particle therapy relies on the consistency of spot position information recorded by the spot position monitor (SPM), but practical methods for routine independent verification of these coordinates remain limited. PURPOSE: This study describes a practical framework for routine verification of SPM coordinate consistency using independent scintillator-based measurements in raster-scanning carbon-ion radiotherapy.
methodsReference spot positions were measured at the isocenter plane using a scintillator-based detector. Corresponding SPM-recorded spot coordinates were extracted from delivery log files. The two coordinate sets were aligned using a similarity transformation accounting for translation, rotation, and isotropic scaling. Post-transformation root-mean-square (RMS) residuals were used as a practical consistency metric reflecting the agreement between SPM-reported and independently measured spot positions under routine QA conditions.
resultsAfter similarity transformation, the median RMS residual across all investigated accelerator energies and irradiation ports was 1.45 mm, with an interquartile range of 1.36-1.63 mm. No statistically significant difference was detected across accelerator energies, whereas a significant difference was observed among irradiation ports.
conclusionsThe proposed framework provides a practical approach for routine verification of SPM coordinate consistency and for establishing facility-specific baselines through longitudinal monitoring. The RMS residual should not be interpreted as the intrinsic positional error of the SPM alone, but to provide a framework for establishing a facility-specific baseline for monitoring the agreement between SPM-reported and independently measured spot coordinates under routine QA conditions.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
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.