eprintid: 10067950 rev_number: 17 eprint_status: archive userid: 608 dir: disk0/10/06/79/50 datestamp: 2019-02-19 12:20:42 lastmod: 2021-12-16 01:28:55 status_changed: 2019-02-19 12:20:42 type: article metadata_visibility: show creators_name: Javaherian, A creators_name: Holman, S title: A continuous adjoint for photo-acoustic tomography of the brain ispublished: pub divisions: UCL divisions: B04 divisions: C05 divisions: F42 note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. abstract: We present an optimisation framework for photo-acoustic tomography of the brain based on a system of coupled equations that describe the propagation of sound waves in linear isotropic inhomogeneous and lossy elastic media with absorption and physical dispersion following a frequency power law using fractional Laplacian operators. The adjoint of the associated continuous forward operator is derived, and a numerical framework for computing this adjoint based on a k-space pseudo-spectral method is presented. We analytically show that the derived continuous adjoint matches the adjoint of an associated discretised forward operator. We include this adjoint in a first-order positivity constrained optimisation algorithm that is regularised by total variation minimisation, and show that the iterates monotonically converge to a minimiser of an objective function, even in the presence of some error in estimating the physical parameters of the medium. date: 2018-08 date_type: published publisher: IOP PUBLISHING LTD official_url: https://doi.org/10.1088/1361-6420/aac530 oa_status: green full_text_type: other language: eng primo: open primo_central: open_green article_type_text: Article verified: verified_manual elements_id: 1572124 doi: 10.1088/1361-6420/aac530 language_elements: English lyricists_name: Javaherian, Ashkan lyricists_id: AJAVA16 actors_name: Javaherian, Ashkan actors_id: AJAVA16 actors_role: owner full_text_status: public publication: Inverse Problems volume: 34 number: 8 pages: 31 issn: 1361-6420 citation: Javaherian, A; Holman, S; (2018) A continuous adjoint for photo-acoustic tomography of the brain. Inverse Problems , 34 (8) 10.1088/1361-6420/aac530 <https://doi.org/10.1088/1361-6420%2Faac530>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10067950/1/Javaherian_continuous_adjoint.pdf