Evidence map›Paper›PMID 42775600›Full record

ArticleJournal of applied clinical medical physics2026

Comparative evaluation of VoxelMorpand conventional deformable image registration algorithms for thoracic 4D-CT in radiotherapy.

Mizuha Sakai, Megumi Nakao, Hideaki Hirashima, Masahiro Yoneyama, Noriko Kishi, Takashi Mizowaki, Mitsuhiro Nakamura

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In one paragraph

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.

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4 · The record

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5 · Who and what money

Authors and funding

7 authors.

Mizuha SakaiDepartment of Advanced Medical Physics, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan.
Megumi NakaoDepartment of Biomedical Engineering and Intelligence, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan.
Hideaki HirashimaDepartment of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan.
Masahiro YoneyamaDepartment of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan.
Noriko KishiDepartment of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan.
Takashi MizowakiDepartment of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan.
Mitsuhiro NakamuraDepartment of Advanced Medical Physics, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan.

Funding

JSPS 23K24282
6 · The paper itself

Abstract

backgroundDeformable image registration (DIR) is essential for thoracic four-dimensional computed tomography (4D-CT)-based radiotherapy applications. Recently, deep learning-based DIR methods such as VoxelMorph have been proposed; however, their performance relative to clinically used DIR algorithms remains unclear. PURPOSE: This study aimed to evaluate the DIR accuracy of VoxelMorph for thoracic 4D-CT and to compare it with conventional clinical and research-oriented DIR methods. MATERIALS AND

methodsThoracic 4D-CT data from 64 lung cancer patients were retrospectively analyzed. End-inhalation and end-exhalation phase images were used for DIR. VoxelMorph was trained using 50 cases, with 4 for validation and 10 for testing. DIR performance on the test dataset was compared with Demons (SimpleITK), modified Demons (Eclipse), and ANACONDA (RayStation). Accuracy was evaluated by mean absolute error (MAE) of CT values computed within the body region, whereas Dice similarity coefficient (DSC) and 95th percentile of Hausdorff distance (HD95) were evaluated within the lung label.

resultsThe median MAE decreased from 67.56 HU before DIR to 52.32 HU with modified Demons, 37.39 HU with Demons, 36.18 HU with ANACONDA, and 36.83 HU with VoxelMorph. The median DSC increased from 0.91 to 0.95 for modified Demons, 0.97 for Demons and ANACONDA, and 0.98 for VoxelMorph. The median HD95 was 3.0 mm for modified Demons, 3.1 mm for Demons, 2.0 mm for ANACONDA, and 2.5 mm for VoxelMorph. Overall, VoxelMorph demonstrated competitive accuracy, significantly outperforming modified Demons (adjusted p < 0.05), while showing smaller inter-case variability and markedly reduced processing time.

conclusionsVoxelMorph demonstrated DIR performance comparable to that of clinically used algorithms for thoracic 4D-CT, with high overlap accuracy, relatively low inter-case variability and shorter processing times under the evaluated implementation conditions. These findings suggest its potential as research-oriented DIR framework, although further validation under standardized conditions is required before routine clinical implementation.

Indexed as

AlgorithmsFour-Dimensional Computed TomographyImage Processing, Computer-AssistedLung NeoplasmsRadiotherapy Planning, Computer-AssistedFemaleHumansMaleRadiotherapy DosageRadiotherapy, Intensity-ModulatedRetrospective Studiesdeep‐learning based DIRDeformable image registrationlung cancerThoracic 4D‐CTVoxelMorph

Identifiers

PMID42775600
PMCPMC13598922

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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.