{
  "abstract": "Accurate patient-specific mean glandular dose (MGD) estimation in breast computed tomography (BCT) requires anatomically realistic models, but high-resolution patient-derived phantoms impose high computational demands on Monte Carlo (MC) dosimetry. We previously developed and validated an EGSnrc-based framework for synchrotron propagation-based phase-contrast BCT (PB-PCT) for the first-in-human study at the Australian Synchrotron. With participant imaging commencing, this study aimed to optimize phantom spatial resolution and MC efficiency while maintaining MGD accuracy, for a rapid patient-specific dosimetry. Four patient-specific heterogeneous breast phantoms with varying volume and glandularity were generated from PB-PCT images of mastectomy specimens acquired at 35 keV. The highest-resolution phantom for each specimen served as the reference. Phantoms were downsampled by increasing in-plane voxel size and slice thickness, and MGD was recalculated using EGSnrc/DOSXYZnrc. A 4.5% difference from reference MGD was adopted as the accuracy criterion. Primary photon histories were then reduced to determine the minimum required for acceptable MC precision. A common voxel size of 0.30 x 0.30 x 3.00 mm3 maintained MGD within 4.5% of reference for all four phantoms while reducing voxel number by approximately 20-31-fold. MGD was more sensitive to in-plane voxel size than slice thickness, supporting anisotropic downsampling. Reduced-resolution phantoms enabled a 15-fold reduction in photon histories to 2 x 10^8 while maintaining acceptable statistical uncertainty. Combined optimization reduced computation time from approximately 1600 to 72 min, a 22-fold acceleration. Patient-specific phantoms can be substantially downsampled while maintaining MGD accuracy and markedly reducing computational burden. This optimization provides a foundation for future real-time patient-specific BCT dosimetry.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.03263",
  "author_total": 12,
  "authors": [
    {
      "name": "Amir Entezam"
    },
    {
      "name": "Ashkan Pakzad"
    },
    {
      "name": "Christopher J. Hall"
    },
    {
      "name": "Anton Maksimenko"
    },
    {
      "name": "Matthew J. Cameron"
    },
    {
      "name": "Adam Round"
    },
    {
      "name": "Seyedamir T. Taba"
    },
    {
      "name": "Keith A. Nugent"
    },
    {
      "name": "Daniel Häusermann"
    },
    {
      "name": "Patrick C. Brennan"
    },
    {
      "name": "Timur E. Gureyev"
    },
    {
      "name": "Harry M. Quiney"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/dcjwgh931277r.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.03263",
  "fulltext_url": null,
  "id": "dcjwgh931277r",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.03263",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.med-ph"
    ],
    [
      "openalex",
      "2740|Digital Radiography and Breast Imaging"
    ]
  ],
  "openalex": "W7208746526",
  "pdf_url": "https://arxiv.org/pdf/2609.03263",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-03",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/dcjwgh931277r.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:31Z",
      "native_id": "2609.03263",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.03263"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:physics.med-ph",
      "subfield": "biological-medical"
    }
  ],
  "title": "Fast Patient-Specific Breast CT Dosimetry: 22-Fold Acceleration of Monte Carlo MGD Estimation",
  "title_text": "Fast Patient-Specific Breast CT Dosimetry: 22-Fold Acceleration of Monte Carlo MGD Estimation",
  "type": "preprint",
  "updated_at": "2026-10-30T12:18:31Z",
  "url": "https://research.draconitic.com/paper/dcjwgh931277r",
  "venue": "arXiv",
  "versions": []
}