{
  "abstract": "Quantitative Photoacoustic Tomography (QPAT) aims to recover spatially varying optical and acoustic tissue parameters by utilizing the photoacoustic effect. The associated inverse problem is highly ill-conditioned due to strong coupling between optical absorption, optical scattering, density, and speed of sound. To alleviate the ill-conditioned nature of this problem, an externally generated ultrasonic wavefield is incorporated in addition to photoacoustic sources, resulting in a multimodal formulation of QPAT. We present a fully coupled, one-step QPAT reconstruction method for the simultaneous recovery of optical absorption, density, and compressibility directly from measurement data, with speed of sound obtained as a derived property. Conventional QPAT and multimodal QPAT arise as special cases within the proposed method. The approach is formulated as a PDE-constrained optimization problem, and the Fréchet derivative of the complete forward model is derived using an optimize-then-discretize adjoint state method. Two-dimensional numerical simulations demonstrate accurate reconstruction of optical absorption, density, and compressibility.",
  "abstract_shown": true,
  "affiliations": [
    "Corresponding author.",
    "Luleå University of Technology, Department of Computer Science, Electrical- and Space Engineering, Sweden"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 2,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Manne Segerlund"
    },
    {
      "affs": [
        1
      ],
      "name": "Torbjörn Löfqvist"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/a1gh8dmgx5psh.bib",
  "cited_by": 1,
  "doi": "10.1016/j.pacs.2026.100872",
  "fulltext_url": "http://www.sciencedirect.com/science/article/pii/S2213597926000789",
  "id": "a1gh8dmgx5psh",
  "issns": [
    "2213-5979"
  ],
  "landing_url": "https://doi.org/10.1016/j.pacs.2026.100872",
  "language": "en",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "lcc",
      "QC1-999"
    ],
    [
      "lcc",
      "QC221-246"
    ],
    [
      "lcc",
      "QC350-467"
    ],
    [
      "openalex",
      "2204|Photoacoustic and Ultrasonic Imaging"
    ]
  ],
  "openalex": "W7204227906",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-29",
  "publisher": "Elsevier",
  "ris": "https://research.draconitic.com/paper/a1gh8dmgx5psh.ris",
  "sources": [
    {
      "first_seen": "2026-10-31T14:22:26Z",
      "native_id": "081b05fa2c004191b2479e5d9d38d3b6",
      "source": "doaj",
      "url": "https://doi.org/10.1016/j.pacs.2026.100872"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "lcc:QC350-467",
      "subfield": "optics-photonics"
    }
  ],
  "title": "A multimodal adjoint-state formulation of Quantitative Photoacoustic Tomography with external acoustic sources",
  "title_text": "A multimodal adjoint-state formulation of Quantitative Photoacoustic Tomography with external acoustic sources",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T14:22:26Z",
  "url": "https://research.draconitic.com/paper/a1gh8dmgx5psh",
  "venue": "Photoacoustics",
  "versions": []
}