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Donato S, Brombal L, Arana Peña LM, Arfelli F, Contillo A, Delogu P, Di Lillo F, Di Trapani V, Fanti V, Longo R, Oliva P, Rigon L, Stori L, Tromba G, Golosio B. Optimization of a customized simultaneous algebraic reconstruction technique algorithm for phase-contrast breast computed tomography. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac65d4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 04/08/2022] [Indexed: 12/22/2022]
Abstract
Abstract
Objective. To introduce the optimization of a customized GPU-based simultaneous algebraic reconstruction technique (cSART) in the field of phase-contrast breast computed tomography (bCT). The presented algorithm features a 3D bilateral regularization filter that can be tuned to yield optimal performance for clinical image visualization and tissues segmentation. Approach. Acquisitions of a dedicated test object and a breast specimen were performed at Elettra, the Italian synchrotron radiation (SR) facility (Trieste, Italy) using a large area CdTe single-photon counting detector. Tomographic images were obtained at 5 mGy of mean glandular dose, with a 32 keV monochromatic x-ray beam in the free-space propagation mode. Three independent algorithms parameters were optimized by using contrast-to-noise ratio (CNR), spatial resolution, and noise texture metrics. The results obtained with the cSART algorithm were compared with conventional SART and filtered back projection (FBP) reconstructions. Image segmentation was performed both with gray scale-based and supervised machine-learning approaches. Main results. Compared to conventional FBP reconstructions, results indicate that the proposed algorithm can yield images with a higher CNR (by 35% or more), retaining a high spatial resolution while preserving their textural properties. Alternatively, at the cost of an increased image ‘patchiness’, the cSART can be tuned to achieve a high-quality tissue segmentation, suggesting the possibility of performing an accurate glandularity estimation potentially of use in the realization of realistic 3D breast models starting from low radiation dose images. Significance. The study indicates that dedicated iterative reconstruction techniques could provide significant advantages in phase-contrast bCT imaging. The proposed algorithm offers great flexibility in terms of image reconstruction optimization, either toward diagnostic evaluation or image segmentation.
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Brombal L, Arana Peña LM, Arfelli F, Longo R, Brun F, Contillo A, Di Lillo F, Tromba G, Di Trapani V, Donato S, Menk RH, Rigon L. Motion artifacts assessment and correction using optical tracking in synchrotron radiation breast CT. Med Phys 2021; 48:5343-5355. [PMID: 34252212 PMCID: PMC9291820 DOI: 10.1002/mp.15084] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 05/12/2021] [Accepted: 06/21/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose The SYRMA‐3D collaboration is setting up a breast computed tomography (bCT) clinical program at the Elettra synchrotron radiation facility in Trieste, Italy. Unlike the few dedicated scanners available at hospitals, synchrotron radiation bCT requires the patient's rotation, which in turn implies a long scan duration (from tens of seconds to few minutes). At the same time, it allows the achievement of high spatial resolution. These features make synchrotron radiation bCT prone to motion artifacts. This article aims at assessing and compensating for motion artifacts through an optical tracking approach. Methods In this study, patients’ movements due to breathing have been first assessed on seven volunteers and then simulated during the CT scans of a breast phantom and a surgical specimen, by adding a periodic oscillatory motion (constant speed, 1 mm amplitude, 12 cycles/minute). CT scans were carried out at 28 keV with a mean glandular dose of 5 mGy. Motion artifacts were evaluated and a correction algorithm based on the optical tracking of fiducial marks was introduced. A quantitative analysis based on the structural similarity (SSIM) index and the normalized mean square error (nMSE) was performed on the reconstructed CT images. Results CT images reconstructed through the optical tracking procedure were found to be as good as the motionless reference image. Moreover, the analysis of SSIM and nMSE demonstrated that an uncorrected motion of the order of the system's point spread function (around 0.1 mm in the present case) can be tolerated. Conclusions Results suggest that a motion correction procedure based on an optical tracking system would be beneficial in synchrotron radiation bCT.
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Affiliation(s)
- Luca Brombal
- Department of Physics, University of Trieste, Trieste, Italy.,Division of Trieste, Istituto Nazionale di Fisica Nucleare, Trieste, Italy
| | - Lucia Mariel Arana Peña
- Department of Physics, University of Trieste, Trieste, Italy.,Division of Trieste, Istituto Nazionale di Fisica Nucleare, Trieste, Italy
| | - Fulvia Arfelli
- Department of Physics, University of Trieste, Trieste, Italy.,Division of Trieste, Istituto Nazionale di Fisica Nucleare, Trieste, Italy
| | - Renata Longo
- Department of Physics, University of Trieste, Trieste, Italy.,Division of Trieste, Istituto Nazionale di Fisica Nucleare, Trieste, Italy
| | - Francesco Brun
- Division of Trieste, Istituto Nazionale di Fisica Nucleare, Trieste, Italy.,Department of Engineering and Architecture, University of Trieste, Trieste, Italy
| | | | | | | | - Vittorio Di Trapani
- Department of Physical sciences, Earth and environment, University of Siena, Siena, Italy.,Division of Pisa, Istituto Nazionale di Fisica Nucleare, Pisa, Italy
| | - Sandro Donato
- Department of Physics, University of Calabria, Arcavacata di Rende, Cosenza, Italy.,Division of Frascati, Istituto Nazionale di Fisca Nucleare, Frascati, Rome, Italy
| | - Ralf Hendrik Menk
- Division of Trieste, Istituto Nazionale di Fisica Nucleare, Trieste, Italy.,Elettra-Sincrotrone Trieste S.C.p.A., Trieste, Italy.,Department of Medical Imaging, University of Saskatchewan, Saskatoon, Canada
| | - Luigi Rigon
- Department of Physics, University of Trieste, Trieste, Italy.,Division of Trieste, Istituto Nazionale di Fisica Nucleare, Trieste, Italy
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Piai A, Contillo A, Arfelli F, Bonazza D, Brombal L, Assunta Cova M, Delogu P, Di Trapani V, Donato S, Golosio B, Mettivier G, Oliva P, Rigon L, Taibi A, Tonutti M, Tromba G, Zanconati F, Longo R. Quantitative characterization of breast tissues with dedicated CT imaging. Phys Med Biol 2019; 64:155011. [PMID: 31234148 DOI: 10.1088/1361-6560/ab2c29] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A quantitative characterization of the soft tissues composing the human breast is achieved by means of a monochromatic CT phase-contrast imaging system, through accurate measurements of their attenuation coefficients within the energy range of interest for breast CT clinical examinations. Quantitative measurements of linear attenuation coefficients are performed on tomographic reconstructions of surgical samples, using monochromatic x-ray beams from a synchrotron source and a free space propagation setup. An online calibration is performed on the obtained reconstructions, in order to reassess the validity of the standard calibration procedure of the CT scanner. Three types of healthy tissues (adipose, glandular, and skin) and malignant tumors, when present, are considered from each sample. The measured attenuation coefficients are in very good agreement with the outcomes of similar studies available in the literature, although they span an energy range that was mostly neglected in the previous studies. No globally significant differences are observed between healthy and malignant dense tissues, although the number of considered samples does not appear sufficient to address the issue of a quantitative differentiation of tumors. The study assesses the viability of the proposed methodology for the measurement of linear attenuation coefficients, and provides a denser sampling of attenuation data in the energy range useful to breast CT.
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Affiliation(s)
- Anna Piai
- Department of Physics, University of Trieste, Via Valerio 2, 34127 Trieste, Italy. INFN Division of Trieste, Via Valerio 2, 34127 Trieste, Italy. Present address: Department of Physics, University of Milan, Via G. Celoria 16, 20133 Milano, Italy
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Longo R, Arfelli F, Bonazza D, Bottigli U, Brombal L, Contillo A, Cova MA, Delogu P, Di Lillo F, Di Trapani V, Donato S, Dreossi D, Fanti V, Fedon C, Golosio B, Mettivier G, Oliva P, Pacilè S, Sarno A, Rigon L, Russo P, Taibi A, Tonutti M, Zanconati F, Tromba G. Advancements towards the implementation of clinical phase-contrast breast computed tomography at Elettra. JOURNAL OF SYNCHROTRON RADIATION 2019; 26:1343-1353. [PMID: 31274463 DOI: 10.1107/s1600577519005502] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 04/23/2019] [Indexed: 06/09/2023]
Abstract
Breast computed tomography (BCT) is an emerging application of X-ray tomography in radiological practice. A few clinical prototypes are under evaluation in hospitals and new systems are under development aiming at improving spatial and contrast resolution and reducing delivered dose. At the same time, synchrotron-radiation phase-contrast mammography has been demonstrated to offer substantial advantages when compared with conventional mammography. At Elettra, the Italian synchrotron radiation facility, a clinical program of phase-contrast BCT based on the free-space propagation approach is under development. In this paper, full-volume breast samples imaged with a beam energy of 32 keV delivering a mean glandular dose of 5 mGy are presented. The whole acquisition setup mimics a clinical study in order to evaluate its feasibility in terms of acquisition time and image quality. Acquisitions are performed using a high-resolution CdTe photon-counting detector and the projection data are processed via a phase-retrieval algorithm. Tomographic reconstructions are compared with conventional mammographic images acquired prior to surgery and with histologic examinations. Results indicate that BCT with monochromatic beam and free-space propagation phase-contrast imaging provide relevant three-dimensional insights of breast morphology at clinically acceptable doses and scan times.
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Affiliation(s)
- Renata Longo
- Department of Physics, University of Trieste, 34127 Trieste, Italy
| | - Fulvia Arfelli
- Department of Physics, University of Trieste, 34127 Trieste, Italy
| | - Deborah Bonazza
- Department of Medical Science, Cattinara Hospital, University of Trieste, 34149 Trieste, Italy
| | - Ubaldo Bottigli
- Department of Physical Sciences, Earth and Environment, University of Siena, 53100 Siena, Italy
| | - Luca Brombal
- Department of Physics, University of Trieste, 34127 Trieste, Italy
| | - Adriano Contillo
- Department of Physics and Earth Science, University of Ferrara, 44122 Ferrara, Italy
| | - Maria A Cova
- Department of Medical Science, Cattinara Hospital, University of Trieste, 34149 Trieste, Italy
| | - Pasquale Delogu
- Department of Physical Sciences, Earth and Environment, University of Siena, 53100 Siena, Italy
| | - Francesca Di Lillo
- Department of Physics `E. Pancini', University of Napoli `Federico II', 80126 Napoli, Italy
| | - Vittorio Di Trapani
- Department of Physical Sciences, Earth and Environment, University of Siena, 53100 Siena, Italy
| | - Sandro Donato
- Department of Physics, University of Trieste, 34127 Trieste, Italy
| | - Diego Dreossi
- Elettra-Sincrotrone Trieste SCpA, 34149 Trieste, Italy
| | - Viviana Fanti
- Department of Physics, University of Cagliari, 09042 Monserrato (CA), Italy
| | | | - Bruno Golosio
- Department of Physics, University of Cagliari, 09042 Monserrato (CA), Italy
| | - Giovanni Mettivier
- Department of Physics `E. Pancini', University of Napoli `Federico II', 80126 Napoli, Italy
| | | | - Serena Pacilè
- Elettra-Sincrotrone Trieste SCpA, 34149 Trieste, Italy
| | - Antonio Sarno
- Department of Physics `E. Pancini', University of Napoli `Federico II', 80126 Napoli, Italy
| | - Luigi Rigon
- Department of Physics, University of Trieste, 34127 Trieste, Italy
| | - Paolo Russo
- Department of Physics `E. Pancini', University of Napoli `Federico II', 80126 Napoli, Italy
| | - Angelo Taibi
- Department of Physics and Earth Science, University of Ferrara, 44122 Ferrara, Italy
| | - Maura Tonutti
- ASUITS, Trieste University Hospital, Department of Radiology, 34100 Trieste, Italy
| | - Fabrizio Zanconati
- Department of Medical Science, Cattinara Hospital, University of Trieste, 34149 Trieste, Italy
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Brombal L, Golosio B, Arfelli F, Bonazza D, Contillo A, Delogu P, Donato S, Mettivier G, Oliva P, Rigon L, Taibi A, Tromba G, Zanconati F, Longo R. Monochromatic breast computed tomography with synchrotron radiation: phase-contrast and phase-retrieved image comparison and full-volume reconstruction. J Med Imaging (Bellingham) 2018; 6:031402. [PMID: 30525064 DOI: 10.1117/1.jmi.6.3.031402] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 07/18/2018] [Indexed: 11/14/2022] Open
Abstract
A program devoted to performing the first in vivo synchrotron radiation (SR) breast computed tomography (BCT) is ongoing at the Elettra facility. Using the high spatial coherence of SR, phase-contrast (PhC) imaging techniques can be used. The latest high-resolution BCT acquisitions of breast specimens, obtained with the propagation-based PhC approach, are herein presented as part of the SYRMA-3D collaboration effort toward the clinical exam. Images are acquired with a 60 - μ m pixel dead-time-free single-photon-counting CdTe detector. The samples are imaged at 32 and 38 keV in a continuous rotating mode, delivering 5 to 20 mGy of mean glandular dose. Contrast-to-noise ratio (CNR) and spatial resolution performances are evaluated for both PhC and phase-retrieved images, showing that by applying the phase-retrieval algorithm a five-time CNR increase can be obtained with a minor loss in spatial resolution across soft tissue interfaces. It is shown that, despite having a poorer CNR, PhC images can provide a sharper visualization of microcalcifications, thus being complementary to phase-retrieved images. Furthermore, the first full-volume scan of a mastectomy sample ( 9 × 9 × 3 cm 3 ) is reported. This investigation into surgical specimens indicates that SR BCT in terms of CNR, spatial resolution, scan duration, and scan volume is feasible.
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Affiliation(s)
- Luca Brombal
- University of Trieste, Department of Physics, Trieste, Italy.,INFN Division of Trieste, Trieste, Italy
| | - Bruno Golosio
- University of Cagliari, Department of Physics, Cagliari, Italy.,INFN Division of Cagliari, Cagliari, Italy
| | - Fulvia Arfelli
- University of Trieste, Department of Physics, Trieste, Italy.,INFN Division of Trieste, Trieste, Italy
| | - Deborah Bonazza
- University of Trieste, Department of Medical Science, Cattinara Hospital, Trieste, Italy
| | - Adriano Contillo
- University of Ferrara, Department of Physics and Earth Science, Ferrara, Italy.,INFN Division of Ferrara, Ferrara, Italy
| | - Pasquale Delogu
- University of Siena, Department of Physical Sciences, Earth and Environment, Siena, Italy.,INFN Division of Pisa, Pisa, Italy
| | - Sandro Donato
- University of Trieste, Department of Physics, Trieste, Italy.,INFN Division of Trieste, Trieste, Italy
| | - Giovanni Mettivier
- University of Napoli Federico II, Department of Physics, Napoli, Italy.,INFN Division of Napoli, Napoli, Italy
| | - Piernicola Oliva
- University of Sassari, Department of Chemistry and Pharmacy, Sassari, Italy.,INFN Division of Cagliari, Cagliari, Italy
| | - Luigi Rigon
- University of Trieste, Department of Physics, Trieste, Italy.,INFN Division of Trieste, Trieste, Italy
| | - Angelo Taibi
- University of Ferrara, Department of Physics and Earth Science, Ferrara, Italy.,INFN Division of Ferrara, Ferrara, Italy
| | | | - Fabrizio Zanconati
- University of Trieste, Department of Medical Science, Cattinara Hospital, Trieste, Italy
| | - Renata Longo
- University of Trieste, Department of Physics, Trieste, Italy.,INFN Division of Trieste, Trieste, Italy
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Brombal L, Donato S, Brun F, Delogu P, Fanti V, Oliva P, Rigon L, Di Trapani V, Longo R, Golosio B. Large-area single-photon-counting CdTe detector for synchrotron radiation computed tomography: a dedicated pre-processing procedure. JOURNAL OF SYNCHROTRON RADIATION 2018; 25:1068-1077. [PMID: 29979168 DOI: 10.1107/s1600577518006197] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
Large-area CdTe single-photon-counting detectors are becoming more and more attractive in view of low-dose imaging applications due to their high efficiency, low intrinsic noise and absence of a scintillating screen which affects spatial resolution. At present, however, since the dimensions of a single sensor are small (typically a few cm2), multi-module architectures are needed to obtain a large field of view. This requires coping with inter-module gaps and with close-to-edge pixels, which generally show a non-optimal behavior. Moreover, high-Z detectors often show gain variations in time due to charge trapping: this effect is detrimental especially in computed tomography (CT) applications where a single tomographic image requires hundreds of projections continuously acquired in several seconds. This work has been carried out at the SYRMEP beamline of the Elettra synchrotron radiation facility (Trieste, Italy), in the framework of the SYRMA-3D project, which aims to perform the world's first breast-CT clinical study with synchrotron radiation. An ad hoc data pre-processing procedure has been developed for the PIXIRAD-8 CdTe single-photon-counting detector, comprising an array of eight 30.7 mm × 24.8 mm modules tiling a 246 mm × 25 mm sensitive area, which covers the full synchrotron radiation beam. The procedure consists of five building blocks, namely dynamic flat-fielding, gap seaming, dynamic ring removal, projection despeckling and around-gap equalization. Each block is discussed and compared, when existing, with conventional approaches. The effectiveness of the pre-processing is demonstrated for phase-contrast CT images of a human breast specimen. The dynamic nature of the proposed procedure, which provides corrections dependent upon the projection index, allows the effective removal of time-dependent artifacts, preserving the main image features including phase effects.
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Affiliation(s)
- Luca Brombal
- Department of Physics, University of Trieste, 34127 Trieste, Italy
| | - Sandro Donato
- Department of Physics, University of Trieste, 34127 Trieste, Italy
| | | | - Pasquale Delogu
- Department of Physical Sciences, Earth and Environment, University of Siena, 53100 Siena, Italy
| | - Viviana Fanti
- Department of Physics, University of Cagliari, 09042 Monserrato (CA), Italy
| | | | - Luigi Rigon
- Department of Physics, University of Trieste, 34127 Trieste, Italy
| | - Vittorio Di Trapani
- Department of Physical Sciences, Earth and Environment, University of Siena, 53100 Siena, Italy
| | - Renata Longo
- Department of Physics, University of Trieste, 34127 Trieste, Italy
| | - Bruno Golosio
- Department of Physics, University of Cagliari, 09042 Monserrato (CA), Italy
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