Evidence map›Paper›PMID 41732734›Full record

ArticlePhysics and imaging in radiation oncology2026

Inverse consistency error for validating deformable image registration: an explorative study on computational phantoms.

Gianfranco Loi, Marco Fusella, Stefania Zara, Marica Vagni, Nicola Michielli, Orlando Zaccaria, Lorenzo Placidi, Pierfrancesco Franco, Filippo Molinari, Christian Fiandra

Abstract read
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Article in Physics and imaging in radiation oncology, 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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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

10 authors.

Gianfranco LoiAzienda Ospedaliero-Universitaria Maggiore della Carità, Novara, Italy.
Marco FusellaAbano Terme Hospital, Department of Radiation Oncology, Abano Terme, Padua, Italy.
Stefania ZaraTecnologie Avanzate Srl, Turin, Italy.
Marica VagniUniversità Cattolica del Sacro Cuore, Campus di Roma, Rome, Italy.
Nicola MichielliPoliToBIOMed Lab, Department of Electronics and Telecommunications, Politecnico di Torino, Turin, Italy.
Orlando ZaccariaTecnologie Avanzate Srl, Turin, Italy.
Lorenzo PlacidiDiagnostic Imaging and Oncological Radiotherapy Department Fondazione Policlinico Universitario A. Gemelli, Rome, Italy.
Pierfrancesco FrancoAzienda Ospedaliero-Universitaria Maggiore della Carità, Novara, Italy.
Filippo MolinariPoliToBIOMed Lab, Department of Electronics and Telecommunications, Politecnico di Torino, Turin, Italy.
Christian FiandraAzienda Ospedaliero Universitaria (AOU) Città della Salute e della Scienza, Presidio Molinette, Turin, Italy.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Background and Purpose: Validation of deformable image registration (DIR) remains predominantly contourbased; this study evaluated inverse consistency error (ICE) as an automated voxelwise metric for DIR accuracy. Materials and Methods: Synthetic ground-truth DVFs were generated using geometric and head-and-neck (HN) digital phantoms undergoing controlled global and local deformations. DIR was performed with the ANACONDA algorithm in RayStation. ICE maps derived from clinical DVFs were compared with ground-truth registration error (GTRE), target registration error (TRE) from 20 anatomical landmarks, and mean distance to agreement (MDA) for 22 propagated ROIs. Results: Ground-truth DVFs showed negligible ICE values, confirming mathematical invertibility. In HN phantoms, median ICE and GTRE were 0.8 ± 0.2 mm and 1.6 ± 0.4 mm, respectively. ICE correlated strongly with GTRE (R = 0.85, p < 0.001) and moderately with TRE (R = 0.68, p < 0.001). No significant correlation was found with contourbased MDA (2.47 ± 0.18 mm). Voxel-wise analysis showed that ICE captured spatial patterns of uncertainty consistent with regions of higher GTRE, while underestimating error for global homogeneous deformations >15 mm due to DIR regularisation. Across all datasets, ICE correctly identified high-uncertainty subregions that were not detected by contour-based metrics. Conclusions: ICE enables automated voxel-wise quantification of DIR uncertainty directly from clinical DVFs. It complements traditional contour-based metrics and may support patient-specific QA and more reliable dose mapping in adaptive and re-irradiation radiotherapy workflows.

Indexed as

Deformable image registrationInverse consistency errorQuality assuranceRegistration uncertaintyVoxel wise validation

Identifiers

PMID41732734
PMCPMC12925039

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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.