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Dale R, Zheng B, Orihuela-Espina F, Ross N, O’Sullivan TD, Howard S, Dehghani H. Deep learning-enabled high-speed, multi-parameter diffuse optical tomography. JOURNAL OF BIOMEDICAL OPTICS 2024; 29:076004. [PMID: 39035576 PMCID: PMC11259453 DOI: 10.1117/1.jbo.29.7.076004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2024] [Revised: 05/22/2024] [Accepted: 06/20/2024] [Indexed: 07/23/2024]
Abstract
Significance Frequency-domain diffuse optical tomography (FD-DOT) could enhance clinical breast tumor characterization. However, conventional diffuse optical tomography (DOT) image reconstruction algorithms require case-by-case expert tuning and are too computationally intensive to provide feedback during a scan. Deep learning (DL) algorithms front-load computational and tuning costs, enabling high-speed, high-fidelity FD-DOT. Aim We aim to demonstrate a simultaneous reconstruction of three-dimensional absorption and reduced scattering coefficients using DL-FD-DOT, with a view toward real-time imaging with a handheld probe. Approach A DL model was trained to solve the DOT inverse problem using a realistically simulated FD-DOT dataset emulating a handheld probe for human breast imaging and tested using both synthetic and experimental data. Results Over a test set of 300 simulated tissue phantoms for absorption and scattering reconstructions, the DL-DOT model reduced the root mean square error by 12 % ± 40 % and 23 % ± 40 % , increased the spatial similarity by 17 % ± 17 % and 9 % ± 15 % , increased the anomaly contrast accuracy by 9 % ± 9 % (μ a ), and reduced the crosstalk by 5 % ± 18 % and 7 % ± 11 % , respectively, compared with model-based tomography. The average reconstruction time was reduced from 3.8 min to 0.02 s for a single reconstruction. The model was successfully verified using two tumor-emulating optical phantoms. Conclusions There is clinical potential for real-time functional imaging of human breast tissue using DL and FD-DOT.
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Affiliation(s)
- Robin Dale
- University of Birmingham, School of Computer Science, Medical Imaging Lab, Birmingham, United Kingdom
| | - Biao Zheng
- University of Birmingham, School of Computer Science, Medical Imaging Lab, Birmingham, United Kingdom
| | - Felipe Orihuela-Espina
- University of Birmingham, School of Computer Science, Medical Imaging Lab, Birmingham, United Kingdom
| | - Nicholas Ross
- University of Notre Dame, Department of Electrical Engineering, Notre Dame, Indiana, United States
| | - Thomas D. O’Sullivan
- University of Notre Dame, Department of Electrical Engineering, Notre Dame, Indiana, United States
| | - Scott Howard
- University of Notre Dame, Department of Electrical Engineering, Notre Dame, Indiana, United States
| | - Hamid Dehghani
- University of Birmingham, School of Computer Science, Medical Imaging Lab, Birmingham, United Kingdom
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2
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Soydan DA, Top CB, Gençer NG. On the utilization of the adjoint method in microwave tomography. INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING 2024; 40:e3818. [PMID: 38556485 DOI: 10.1002/cnm.3818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 03/14/2024] [Accepted: 03/17/2024] [Indexed: 04/02/2024]
Abstract
In microwave imaging, the adjoint method is widely used for the efficient calculation of the update direction, which is then used to update the unknown model parameter. However, the utilization and the formulation of the adjoint method differ significantly depending on the imaging scenario and the applied optimization algorithm. Because of the problem-specific nature of the adjoint formulations, the dissimilarities between the adjoint calculations may be overlooked. Here, we have classified the adjoint method formulations into two groups: the direct and indirect methods. The direct method involves calculating the derivative of the cost function, whereas, in the indirect method, the derivative of the predicted data is calculated. In this review, the direct and indirect adjoint methods are presented, compared, and discussed. The formulations are explicitly derived using the two-dimensional wave equation in frequency and time domains. Finite-difference time-domain simulations are conducted to show the different uses of the adjoint methods for both single source-multiple receiver, and multiple transceiver scenarios. This study demonstrated that an appropriate adjoint method selection is significant to achieve improved computational efficiency for the applied optimization algorithm.
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Affiliation(s)
- Damla Alptekin Soydan
- Electrical and Electronics Engineering Department, Middle East Technical University, Ankara, Turkey
- ASELSAN A.Ş, Ankara, Turkey
| | | | - Nevzat G Gençer
- Electrical and Electronics Engineering Department, Middle East Technical University, Ankara, Turkey
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3
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Ren W, Ni R. Noninvasive Visualization of Amyloid-Beta Deposits in Alzheimer's Amyloidosis Mice via Fluorescence Molecular Tomography Using Contrast Agent. Methods Mol Biol 2024; 2785:271-285. [PMID: 38427199 DOI: 10.1007/978-1-0716-3774-6_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Alzheimer's disease is pathologically featured by the accumulation of amyloid-beta (Aβ) plaque and neurofibrillary tangles. Compared to small animal positron emission tomography, optical imaging features nonionizing radiation, low cost, and logistic convenience. Optical detection of Aβ deposits is typically implemented by 2D macroscopic imaging and various microscopic techniques assisted with Aβ-targeted contrast agents. Here, we introduce fluorescence molecular tomography (FMT), a macroscopic 3D fluorescence imaging technique, convenient for in vivo longitudinal monitoring of the animal brain without the involvement of cranial window opening operation. This chapter aims to provide the protocols for FMT in vivo imaging of Aβ deposits in the brain of rodent model of Alzheimer's disease. The materials, stepwise method, notes, limitations of FMT, and emerging opportunities for FMT techniques are presented.
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Affiliation(s)
- Wuwei Ren
- School of Information Science and Technology, ShanghaiTech University, Shanghai, China.
| | - Ruiqing Ni
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
- Institute for Biomedical Engineering, ETH Zurich & University of Zurich, Zurich, Switzerland
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4
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Vanegas M, Mireles M, Xu E, Yan S, Fang Q. Compact breast shape acquisition system for improving diffuse optical tomography image reconstructions. BIOMEDICAL OPTICS EXPRESS 2023; 14:1579-1593. [PMID: 37078036 PMCID: PMC10110328 DOI: 10.1364/boe.481092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/23/2022] [Accepted: 01/04/2023] [Indexed: 05/03/2023]
Abstract
Diffuse optical tomography (DOT) has been investigated for diagnosing malignant breast lesions, but its accuracy relies on model-based image reconstructions, which in turn depends on the accuracy of breast shape acquisition. In this work, we have developed a dual-camera structured light imaging (SLI) breast shape acquisition system tailored for a mammography-like compression setting. Illumination pattern intensity is dynamically adjusted to account for skin tone differences, while thickness-informed pattern masking reduces artifacts due to specular reflections. This compact system is affixed to a rigid mount that can be installed into existing mammography or parallel-plate DOT systems without the need for camera-projector re-calibration. Our SLI system produces sub-millimeter resolution with a mean surface error of 0.26 mm. This breast shape acquisition system results in more accurate surface recovery, with an average 1.6-fold reduction in surface estimation errors over a reference method via contour extrusion. Such improvement translates to 25% to 50% reduction in mean squared error in the recovered absorption coefficient for a series of simulated tumors 1-2 cm below the skin.
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Affiliation(s)
- Morris Vanegas
- Department of Bioengineering, Northeastern University, Boston, MA 02115, USA
| | - Miguel Mireles
- Department of Bioengineering, Northeastern University, Boston, MA 02115, USA
| | - Edward Xu
- Department of Bioengineering, Northeastern University, Boston, MA 02115, USA
| | - Shijie Yan
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA 02115, USA
| | - Qianqian Fang
- Department of Bioengineering, Northeastern University, Boston, MA 02115, USA
- Department of Electrical and Computer Engineering, Northeastern University, Boston, MA 02115, USA
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5
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Yuliansyah DR, Pan MC, Hsu YF. Sensor-to-Image Based Neural Networks: A Reliable Reconstruction Method for Diffuse Optical Imaging of High-Scattering Media. SENSORS (BASEL, SWITZERLAND) 2022; 22:9096. [PMID: 36501794 PMCID: PMC9741421 DOI: 10.3390/s22239096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/16/2022] [Accepted: 11/20/2022] [Indexed: 06/17/2023]
Abstract
Imaging tasks today are being increasingly shifted toward deep learning-based solutions. Biomedical imaging problems are no exception toward this tendency. It is appealing to consider deep learning as an alternative to such a complex imaging task. Although research of deep learning-based solutions continues to thrive, challenges still remain that limits the availability of these solutions in clinical practice. Diffuse optical tomography is a particularly challenging field since the problem is both ill-posed and ill-conditioned. To get a reconstructed image, various regularization-based models and procedures have been developed in the last three decades. In this study, a sensor-to-image based neural network for diffuse optical imaging has been developed as an alternative to the existing Tikhonov regularization (TR) method. It also provides a different structure compared to previous neural network approaches. We focus on realizing a complete image reconstruction function approximation (from sensor to image) by combining multiple deep learning architectures known in imaging fields that gives more capability to learn than the fully connected neural networks (FCNN) and/or convolutional neural networks (CNN) architectures. We use the idea of transformation from sensor- to image-domain similarly with AUTOMAP, and use the concept of an encoder, which is to learn a compressed representation of the inputs. Further, a U-net with skip connections to extract features and obtain the contrast image, is proposed and implemented. We designed a branching-like structure of the network that fully supports the ring-scanning measurement system, which means it can deal with various types of experimental data. The output images are obtained by multiplying the contrast images with the background coefficients. Our network is capable of producing attainable performance in both simulation and experiment cases, and is proven to be reliable to reconstruct non-synthesized data. Its apparent superior performance was compared with the results of the TR method and FCNN models. The proposed and implemented model is feasible to localize the inclusions with various conditions. The strategy created in this paper can be a promising alternative solution for clinical breast tumor imaging applications.
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Affiliation(s)
| | - Min-Chun Pan
- Department of Mechanical Engineering, National Central University, Taoyuan City 320, Taiwan
| | - Ya-Fen Hsu
- Department of Surgery, Landseed International Hospital, Taoyuan City 324, Taiwan
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6
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Zhang N, Zhang Q, Nurmikko A. Sub-mm resolution tomographic imaging in turbid media by an ultra-high density multichannel approach. BIOMEDICAL OPTICS EXPRESS 2022; 13:5926-5936. [PMID: 36733739 PMCID: PMC9872878 DOI: 10.1364/boe.470724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 10/05/2022] [Accepted: 10/05/2022] [Indexed: 05/09/2023]
Abstract
We demonstrate an ultra-high-density source-detector (SD) diffuse optical tomography system scalable to thousands of combinatorial SD pairs per cm3 of total voxel volume. We demonstrate the imaging of dynamic targets (including phantom arteries) with 100 um resolution at over 10 Hz frame rate within turbid media (> 60 MFP). Further, as a step toward a wearable mobile imager, we introduce monolithic mm-size dense semiconductor laser array chips as sources for potential unobtrusive epidermal tomographic use.
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Affiliation(s)
- Ning Zhang
- School of Engineering, Brown University, 184 Hope St, Providence, RI, 02912, USA
| | - Quan Zhang
- Massachusetts General Hospital, Harvard Medical School, 13th Street, Charlestown, MA, 02129, USA
| | - Arto Nurmikko
- School of Engineering, Brown University, 184 Hope St, Providence, RI, 02912, USA
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7
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Ben Yedder H, Cardoen B, Shokoufi M, Golnaraghi F, Hamarneh G. Multitask Deep Learning Reconstruction and Localization of Lesions in Limited Angle Diffuse Optical Tomography. IEEE TRANSACTIONS ON MEDICAL IMAGING 2022; 41:515-530. [PMID: 34606449 DOI: 10.1109/tmi.2021.3117276] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Diffuse optical tomography (DOT) leverages near-infrared light propagation through tissue to assess its optical properties and identify abnormalities. DOT image reconstruction is an ill-posed problem due to the highly scattered photons in the medium and the smaller number of measurements compared to the number of unknowns. Limited-angle DOT reduces probe complexity at the cost of increased reconstruction complexity. Reconstructions are thus commonly marred by artifacts and, as a result, it is difficult to obtain an accurate reconstruction of target objects, e.g., malignant lesions. Reconstruction does not always ensure good localization of small lesions. Furthermore, conventional optimization-based reconstruction methods are computationally expensive, rendering them too slow for real-time imaging applications. Our goal is to develop a fast and accurate image reconstruction method using deep learning, where multitask learning ensures accurate lesion localization in addition to improved reconstruction. We apply spatial-wise attention and a distance transform based loss function in a novel multitask learning formulation to improve localization and reconstruction compared to single-task optimized methods. Given the scarcity of real-world sensor-image pairs required for training supervised deep learning models, we leverage physics-based simulation to generate synthetic datasets and use a transfer learning module to align the sensor domain distribution between in silico and real-world data, while taking advantage of cross-domain learning. Applying our method, we find that we can reconstruct and localize lesions faithfully while allowing real-time reconstruction. We also demonstrate that the present algorithm can reconstruct multiple cancer lesions. The results demonstrate that multitask learning provides sharper and more accurate reconstruction.
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8
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Nouizi F, Algarawi M, Erkol H, Luk A, Gulsen G. Multiwavelength photo-magnetic imaging algorithm improved for direct chromophore concentration recovery using spectral constraints. APPLIED OPTICS 2021; 60:10855-10861. [PMID: 35200850 DOI: 10.1364/ao.439250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 11/12/2021] [Indexed: 06/14/2023]
Abstract
Multiwavelength photo-magnetic imaging (PMI) is a novel combination of diffuse optics and magnetic resonance imaging, to the best of our knowledge, that yields tissue chromophore concentration maps with high resolution and quantitative accuracy. Here, we present the first experimental results, to the best of our knowledge, obtained using a spectrally constrained PMI image reconstruction method, where chromophore concentration maps are directly recovered, unlike the conventional two-step approach that requires an intermediate step of reconstructing wavelength-dependent absorption coefficient maps. The imposition of the prior spectral information into the PMI inverse problem improves the reconstructed image quality and allows recovery of highly quantitative concentration maps, which are crucial for effective cancer detection and characterization. The obtained results demonstrate the higher performance of the direct reconstruction method. Indeed, the reconstructed concentration maps are not only of higher quality but also obtained approximately 2 times faster than the conventional method.
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9
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Mudeng V, Kim M, Choe SW. Objective Numerical Evaluation of Diffuse, Optically Reconstructed Images Using Structural Similarity Index. BIOSENSORS 2021; 11:504. [PMID: 34940261 PMCID: PMC8699273 DOI: 10.3390/bios11120504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Revised: 12/06/2021] [Accepted: 12/06/2021] [Indexed: 05/13/2023]
Abstract
Diffuse optical tomography is emerging as a non-invasive optical modality used to evaluate tissue information by obtaining the optical properties' distribution. Two procedures are performed to produce reconstructed absorption and reduced scattering images, which provide structural information that can be used to locate inclusions within tissues with the assistance of a known light intensity around the boundary. These methods are referred to as a forward problem and an inverse solution. Once the reconstructed image is obtained, a subjective measurement is used as the conventional way to assess the image. Hence, in this study, we developed an algorithm designed to numerically assess reconstructed images to identify inclusions using the structural similarity (SSIM) index. We compared four SSIM algorithms with 168 simulated reconstructed images involving the same inclusion position with different contrast ratios and inclusion sizes. A multiscale, improved SSIM containing a sharpness parameter (MS-ISSIM-S) was proposed to represent the potential evaluation compared with the human visible perception. The results indicated that the proposed MS-ISSIM-S is suitable for human visual perception by demonstrating a reduction of similarity score related to various contrasts with a similar size of inclusion; thus, this metric is promising for the objective numerical assessment of diffuse, optically reconstructed images.
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Affiliation(s)
- Vicky Mudeng
- Department of Medical IT Convergence Engineering, Kumoh National Institute of Technology, Gumi 39253, Korea;
- Department of Electrical Engineering, Institut Teknologi Kalimantan, Balikpapan 76127, Indonesia
| | - Minseok Kim
- Department of Mechanical System Engineering, Kumoh National Institute of Technology, Gumi 39177, Korea
- Department of Aeronautics, Mechanical and Electronic Convergence Engineering, Kumoh National Institute of Technology, Gumi 39177, Korea
| | - Se-woon Choe
- Department of Medical IT Convergence Engineering, Kumoh National Institute of Technology, Gumi 39253, Korea;
- Department of IT Convergence Engineering, Kumoh National Institute of Technology, Gumi 39253, Korea
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10
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Wang HL, Chen JW, Yang SH, Lo YC, Pan HC, Liang YW, Wang CF, Yang Y, Kuo YT, Lin YC, Chou CY, Lin SH, Chen YY. Multimodal Optical Imaging to Investigate Spatiotemporal Changes in Cerebrovascular Function in AUDA Treatment of Acute Ischemic Stroke. Front Cell Neurosci 2021; 15:655305. [PMID: 34149359 PMCID: PMC8209306 DOI: 10.3389/fncel.2021.655305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 05/10/2021] [Indexed: 01/03/2023] Open
Abstract
Administration of 12-(3-adamantan-1-yl-ureido)-dodecanoic acid (AUDA) has been demonstrated to alleviate infarction following ischemic stroke. Reportedly, the main effect of AUDA is exerting anti-inflammation and neovascularization via the inhibition of soluble epoxide hydrolase. However, the major contribution of this anti-inflammation and neovascularization effect in the acute phase of stroke is not completely elucidated. To investigate the neuroprotective effects of AUDA in acute ischemic stroke, we combined laser speckle contrast imaging and optical intrinsic signal imaging techniques with the implantation of a lab-designed cranial window. Forepaw stimulation was applied to assess the functional changes via measuring cerebral metabolic rate of oxygen (CMRO2) that accompany neural activity. The rats that received AUDA in the acute phase of photothrombotic ischemia stroke showed a 30.5 ± 8.1% reduction in the ischemic core, 42.3 ± 15.1% reduction in the ischemic penumbra (p < 0.05), and 42.1 ± 4.6% increase of CMRO2 in response to forepaw stimulation at post-stroke day 1 (p < 0.05) compared with the control group (N = 10 for each group). Moreover, at post-stroke day 3, increased functional vascular density was observed in AUDA-treated rats (35.9 ± 1.9% higher than that in the control group, p < 0.05). At post-stroke day 7, a 105.4% ± 16.4% increase of astrocytes (p < 0.01), 30.0 ± 10.9% increase of neurons (p < 0.01), and 65.5 ± 15.0% decrease of microglia (p < 0.01) were observed in the penumbra region in AUDA-treated rats (N = 5 for each group). These results suggested that AUDA affects the anti-inflammation at the beginning of ischemic injury and restores neuronal metabolic rate of O2 and tissue viability. The neovascularization triggered by AUDA restored CBF and may contribute to ischemic infarction reduction at post-stroke day 3. Moreover, for long-term neuroprotection, astrocytes in the penumbra region may play an important role in protecting neurons from apoptotic injury.
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Affiliation(s)
- Han-Lin Wang
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Jia-Wei Chen
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Shih-Hung Yang
- Department of Mechanical Engineering, National Cheng Kung University, Tainan, Taiwan
| | - Yu-Chun Lo
- The Ph.D. Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Han-Chi Pan
- National Laboratory Animal Center, Taipei, Taiwan
| | - Yao-Wen Liang
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Ching-Fu Wang
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yi Yang
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yun-Ting Kuo
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Yi-Chen Lin
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chin-Yu Chou
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Sheng-Huang Lin
- Department of Neurology, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan.,Department of Neurology, School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - You-Yin Chen
- Department of Biomedical Engineering, National Yang Ming Chiao Tung University, Taipei, Taiwan.,The Ph.D. Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
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11
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Radford J, Lyons A, Tonolini F, Faccio D. Role of late photons in diffuse optical imaging. OPTICS EXPRESS 2020; 28:29486-29495. [PMID: 33114848 DOI: 10.1364/oe.402503] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 09/08/2020] [Indexed: 06/11/2023]
Abstract
The ability to image through turbid media, such as organic tissues, is a highly attractive prospect for biological and medical imaging. This is challenging, however, due to the highly scattering properties of tissues which scramble the image information. The earliest photons that arrive at the detector are often associated with ballistic transmission, whilst the later photons are associated with complex paths due to multiple independent scattering events and are therefore typically considered to be detrimental to the final image formation process. In this work, we report on the importance of these highly diffuse, "late" photons for computational time-of-flight diffuse optical imaging. In thick scattering materials, >80 transport mean free paths, we provide evidence that including late photons in the inverse retrieval enhances the image reconstruction quality. We also show that the late photons alone have sufficient information to retrieve images of a similar quality to early photon gated data. This result emphasises the importance in the strongly diffusive regime of fully time-resolved imaging techniques.
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12
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Development of digital breast tomosynthesis and diffuse optical tomography fusion imaging for breast cancer detection. Sci Rep 2020; 10:13127. [PMID: 32753578 PMCID: PMC7403423 DOI: 10.1038/s41598-020-70103-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 07/20/2020] [Indexed: 02/06/2023] Open
Abstract
Diffuse optical tomography (DOT) non-invasively measures the functional characteristics of breast lesions using near infrared light to probe tissue optical properties. This study aimed to evaluate a new digital breast tomosynthesis (DBT)/DOT fusion imaging technique and obtain preliminary data for breast cancer detection. Twenty-eight women were prospectively enrolled and underwent both DBT and DOT examinations. DBT/DOT fusion imaging was created after acquisition of both examinations. Two breast radiologists analyzed DBT and DOT images independently, and then finally evaluated the fusion images. The diagnostic performance of each reading session was compared and interobserver agreement was assessed. The technical success rate was 96.4%, with one failure due to an error during DOT data storage. Among the 27 women finally included in the analysis, 13 had breast cancer. The areas under the receiver operating characteristic curve (AUCs) for DBT were 0.783 and 0.854 for readers 1 and 2, respectively. DOT showed comparable diagnostic performance to DBT for both readers. The AUCs were significantly improved (P = 0.004) when the DBT/DOT fusion images were used. Interobserver agreements were highest for the DBT/DOT fusion images. In conclusion, this study suggests that DBT/DOT fusion imaging technique appears to be a promising tool for breast cancer diagnosis.
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Algarawi M, Erkol H, Luk A, Ha S, Ünlü MB, Gulsen G, Nouizi F. Resolving tissue chromophore concentration at MRI resolution using multi-wavelength photo-magnetic imaging. BIOMEDICAL OPTICS EXPRESS 2020; 11:4244-4254. [PMID: 32923039 PMCID: PMC7449711 DOI: 10.1364/boe.397538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/24/2020] [Accepted: 06/30/2020] [Indexed: 06/11/2023]
Abstract
Photo-magnetic imaging (PMI) is an emerging optical imaging modality that showed great performance on providing absorption maps with high resolution and quantitative accuracy. As a multi-modality technology, PMI warms up the imaged object using a near infrared laser while temperature variation is measured using magnetic resonance imaging. By probing tissue at multiple wavelengths, concentration of the main tissue chromophores such as oxy- and deoxy-hemoglobin, lipid, and water are obtained then used to derive functional parameters such as total hemoglobin concentration and relative oxygen saturation. In this paper, we present a multi-wavelength PMI system that was custom-built to host five different laser wavelengths. After recovering the high-resolution absorption maps, a least-squared minimization process was used to resolve the different chromophore concentration. The performance of the system was experimentally tested on a phantom with two different dyes. Their concentrations were successfully assessed with high spatial resolution and average accuracy of nearly 80%.
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Affiliation(s)
- Maha Algarawi
- Center for Functional Onco-Imaging, University of California Irvine, CA 92697, USA
- Department of Physics and Astronomy, University of California Irvine, CA 92697, USA
| | - Hakan Erkol
- Department of Physics, Bogazici University, Istanbul, Turkey
| | - Alex Luk
- Center for Functional Onco-Imaging, University of California Irvine, CA 92697, USA
| | | | - Mehmet B. Ünlü
- Department of Physics, Bogazici University, Istanbul, Turkey
| | - Gultekin Gulsen
- Center for Functional Onco-Imaging, University of California Irvine, CA 92697, USA
- Department of Physics and Astronomy, University of California Irvine, CA 92697, USA
- Department of Radiological Sciences, University of California Irvine, CA 92697, USA
| | - Farouk Nouizi
- Center for Functional Onco-Imaging, University of California Irvine, CA 92697, USA
- Department of Radiological Sciences, University of California Irvine, CA 92697, USA
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14
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Ren W, Jiang J, Costanzo Mata AD, Kalyanov A, Ripoll J, Lindner S, Charbon E, Zhang C, Rudin M, Wolf M. Multimodal imaging combining time-domain near-infrared optical tomography and continuous-wave fluorescence molecular tomography. OPTICS EXPRESS 2020; 28:9860-9874. [PMID: 32225585 DOI: 10.1364/oe.385392] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/02/2020] [Indexed: 06/10/2023]
Abstract
Fluorescence molecular tomography (FMT) emerges as a powerful non-invasive imaging tool with the ability to resolve fluorescence signals from sources located deep in living tissues. Yet, the accuracy of FMT reconstruction depends on the deviation of the assumed optical properties from the actual values. In this work, we improved the accuracy of the initial optical properties required for FMT using a new-generation time-domain (TD) near-infrared optical tomography (NIROT) system, which effectively decouples scattering and absorption coefficients. We proposed a multimodal paradigm combining TD-NIROT and continuous-wave (CW) FMT. Both numerical simulation and experiments were performed on a heterogeneous phantom containing a fluorescent inclusion. The results demonstrate significant improvement in the FMT reconstruction by taking the NIROT-derived optical properties as prior information. The multimodal method is attractive for preclinical studies and tumor diagnostics since both functional and molecular information can be obtained.
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15
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Method for Quantitative Broadband Diffuse Optical Spectroscopy of Tumor-Like Inclusions. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10041419] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A hybrid reflectance-based diffuse optical imaging (DOI) technique combining discrete wavelength frequency-domain (FD) near-infrared spectroscopy (NIRS) with broadband continuous wave NIRS measurements was developed to quantify the broadband optical properties of deep tumor-like inclusions. This method was developed to more accurately measure the broadband optical properties of human tumors using a compact handheld imaging probe and without requiring a priori spectral constraints. We simulated the reconstruction of absorption and scattering spectra (650–1000 nm) of human breast tumors in a homogeneous background at depths of 0 to 10 mm. The hybrid DOI technique demonstrated enhanced performance in reconstruction of optical absorption with a mean accuracy over all 71 wavelengths of 8.39% versus 32.26% for a 10 mm deep tumor with the topographic DOI method. The new hybrid technique was also tested and validated on two heterogeneous tissue-simulating phantoms with inclusion depths of 2, 7, and 9 mm. The mean optical absorption accuracy over all wavelengths was similarly improved up to 5x for the hybrid DOI method versus topographic DOI for the deepest inclusions.
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16
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Improving Localization of Deep Inclusions in Time-Resolved Diffuse Optical Tomography. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9245468] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Time-resolved diffuse optical tomography is a technique used to recover the optical properties of an unknown diffusive medium by solving an ill-posed inverse problem. In time-domain, reconstructions based on datatypes are used for their computational efficiency. In practice, most used datatypes are temporal windows and Fourier transform. Nevertheless, neither theoretical nor numerical studies assessing different datatypes have been clearly expressed. In this paper, we propose an overview and a new process to compute efficiently a long set of temporal windows in order to perform diffuse optical tomography. We did a theoretical comparison of these large set of temporal windows. We also did simulations in a reflectance geometry with a spherical inclusion at different depths. The results are presented in terms of inclusion localization and its absorption coefficient recovery. We show that (1) the new windows computed with the developed method improve inclusion localization for inclusions at deep layers, (2) inclusion absorption quantification is improved at all depths and, (3) in some cases these windows can be equivalent to frequency based reconstruction at GHz order.
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Broadband Time Domain Diffuse Optical Reflectance Spectroscopy: A Review of Systems, Methods, and Applications. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9245465] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
This review presents recent developments and a wide overview of broadband time domain diffuse optical spectroscopy (TD-DOS). Various topics including physics of photon migration, advanced instrumentation, methods of analysis, applications covering multiple domains (tissue chromophore, in vivo studies, food, wood, pharmaceutical industry) are elaborated. The key role of standardization and recent studies in that direction are discussed. Towards the end, a brief outlook is presented on the current status and future trends in broadband TD-DOS.
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Daly MJ, Chan H, Muhanna N, Akens MK, Wilson BC, Irish JC, Jaffray DA. Intraoperative cone-beam CT spatial priors for diffuse optical fluorescence tomography. ACTA ACUST UNITED AC 2019; 64:215007. [DOI: 10.1088/1361-6560/ab4917] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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19
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Khan AF, Zhang F, Yuan H, Ding L. Dynamic Activation Patterns of the Motor Brain Revealed by Diffuse Optical Tomography . ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2019; 2019:6028-6031. [PMID: 31947220 DOI: 10.1109/embc.2019.8857370] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Diffuse optical tomography (DOT), a subset of functional near-infrared spectroscopy (fNIRS), is a noninvasive functional imaging modality for studying the human brain in normal and diseased conditions. It measures changes in concentrations of oxygenated hemoglobin (HbO) and deoxygenated hemoglobin (Hb) in the blood vasculature of the brain. In contrast to functional magnetic resonance imaging (fMRI), the gold standard in human brain imaging, DOT offers the advantage of higher temporal resolution, portability, lower cost, multiple contrasts and usability for persons who cannot otherwise utilize MRI-based imaging modalities, including bedridden patients and infants, etc. The goal of the present study was to evaluate performance of a DOT method in studying dynamic patterns of brain activations involving motor control. CW-fNIRS data were acquired in four sessions from a healthy male participant when he performed a motor task in a block-design experiment. Results from experimental data showed pronounced activity in the primary motor cortex (M1), contralateral to the clenching hand. It was further observed that the M1 activity was consistent over four sessions. Furthermore, temporal dynamics of motor activity at each session further revealed well-sequenced activation patterns among M1, premotor cortex (PMC), and supplementary motor area (SMA). Timed ipsilateral motor activity suppression was also observed several seconds after the onset of contralateral M1 activity. More importantly, these temporal dynamics were similarly observed in all four sessions. These preliminary results suggest that the DOT method has the sensitivity, reliability, and spatio-temporal resolutions to study activities originated from the motor cortices. A full-scope evaluation and validation in more participants on the motor system can establish it as a promising neuroimaging tool to study, such as, infants at the risk of cerebral palsy or elders with Parkinson's due to its portability and usability in clinical environments.
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Mosca S, Dey P, Tabish TA, Palombo F, Stone N, Matousek P. Spatially Offset and Transmission Raman Spectroscopy for Determination of Depth of Inclusion in Turbid Matrix. Anal Chem 2019; 91:8994-9000. [PMID: 31246425 PMCID: PMC7006960 DOI: 10.1021/acs.analchem.9b01222] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
We
propose an approach for the prediction of the depth of a single
buried object within a turbid medium combining spatially offset Raman
spectroscopy (SORS) and transmission Raman spectroscopy (TRS) and
relying on differential attenuation of individual Raman bands brought
about by the spectral variation of matrix absorption (and scattering).
The relative degree of the Raman band changes is directly related
to the path length of Raman photons traveling through the medium,
thereby encoding the information on the depth of the object within
the matrix. Through a calibration procedure with root mean square
error of calibration (RMSEC) = 3.4%, it was possible to predict the
depth of a paracetamol (acetaminophen) inclusion within a turbid matrix
consisting of polyethylene (PE) by monitoring the relative intensity
of two Raman bands of paracetamol exhibiting differential absorption
by the matrix. The approach was shown to be largely insensitive to
variations of the amount of the inclusion (paracetamol) and to the
overall thickness of the turbid matrix (PE) with a root mean square
error of prediction (RMSEP) maintained below 10% for the tested cases.
This represents a major advantage over previously demonstrated comparable
depth determination Raman approaches (with the exception of full Raman
tomography requiring complex mathematical reconstruction algorithms).
The obtained experimental data validate the proposed approach as an
effective tool for the noninvasive determination of the depth of buried
objects in turbid media with potential applications including determining
noninvasively the depth of a lesion in cancer diagnosis in vivo.
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Affiliation(s)
- Sara Mosca
- Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory , UK Research and Innovation , Harwell Campus, Harwell OX11 0QX , United Kingdom
| | - Priyanka Dey
- School of Physics and Astronomy , University of Exeter , Exeter EX4 4QL , United Kingdom
| | - Tanveer A Tabish
- School of Physics and Astronomy , University of Exeter , Exeter EX4 4QL , United Kingdom
| | - Francesca Palombo
- School of Physics and Astronomy , University of Exeter , Exeter EX4 4QL , United Kingdom
| | - Nicholas Stone
- School of Physics and Astronomy , University of Exeter , Exeter EX4 4QL , United Kingdom
| | - Pavel Matousek
- Central Laser Facility, Research Complex at Harwell, STFC Rutherford Appleton Laboratory , UK Research and Innovation , Harwell Campus, Harwell OX11 0QX , United Kingdom
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Xu S, Shihab Uddin KM, Zhu Q. Improving DOT reconstruction with a Born iterative method and US-guided sparse regularization. BIOMEDICAL OPTICS EXPRESS 2019; 10:2528-2541. [PMID: 31149382 PMCID: PMC6524590 DOI: 10.1364/boe.10.002528] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 03/14/2019] [Accepted: 03/20/2019] [Indexed: 05/22/2023]
Abstract
Ultrasound (US)-guided diffuse optical tomography (DOT) is a promising low-cost imaging technique for diagnosis and assessment of breast cancer. US-guided DOT is best implemented in reflection geometry, which can be co-registered with US pulse-echo imaging and also minimizes the tissue depth for adequate light penetration. However, due to intense light scattering, the DOT reconstruction problem is ill-posed. In this communication, we describe a new non-linear Born iterative reconstruction method with US-guided depth-dependent ℓ 1 sparse regularization for improving DOT reconstruction by incorporating a priori lesion depth and shape information from the co-registered US image. Our method iteratively solves the inverse problem by updating the photon-density wave using the finite difference method, computing the weight matrix based on Born approximation, and reconstructing the absorption map using the fast iterative shrinkage-thresholding optimization algorithm (FISTA). We validate our method using both phantom and patient data and compare the results with those using the first order linear Born method. Phantom experiments demonstrate that the non-linear Born method provides more accurate target absorption reconstruction and better resolution than the linear Born method. Clinical studies on 20 patients show that non-linear Born reconstructs more realistic tumor shapes than linear Born, and improves the malignant-to-benign lesion contrast ratio from 2.73 to 3.07 , which is a 12.5 % improvement. For lesions approximately more than 2.0 cm in diameter, the average malignant-to-benign lesion contrast ratio is increased from 2.68 to 3.31 , which is a 23.5 % improvement.
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Affiliation(s)
- Shiqi Xu
- Elecctrical and Systems Engineering Department, Washington University in St. Louis, 1 Brookings Dr. St. Louis, MO 63130,
USA
| | - K. M. Shihab Uddin
- Biomedical Engineering Department, Washington University in St. Louis, 1 Brookings Dr. St. Louis, MO 63130,
USA
| | - Quing Zhu
- Biomedical Engineering Department, Washington University in St. Louis, 1 Brookings Dr. St. Louis, MO 63130,
USA
- Department of Radiology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, MO 63110,
USA
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22
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Chiarelli AM, Mahmoudzadeh M, Low KA, Maclin EL, Kongolo G, Goudjil S, Fabiani M, Wallois F, Gratton G. Assessment of cerebrovascular development and intraventricular hemorrhages in preterm infants with optical measures of the brain arterial pulse wave. J Cereb Blood Flow Metab 2019; 39:466-480. [PMID: 28949275 PMCID: PMC6421243 DOI: 10.1177/0271678x17732694] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 07/29/2017] [Accepted: 08/21/2017] [Indexed: 12/25/2022]
Abstract
Preterm infants (born at 24-34 weeks of gestational age) suffer from a high incidence of neurological complications. Cerebrovascular lesions (intraventricular hemorrhages, IVH, and ischemic injury) due to the immaturity of the vascular system and its inability to adapt to the extra-uterine environment are the major causes of adverse neurological outcomes. We investigated the feasibility of assessing cerebrovascular status in preterm infants using a novel non-invasive optical procedure, pulse-DOT, usable within the incubator. Pulse-DOT, validated in adults, provides estimates of cerebral arterial status based on optical measurements of the pulse wave. These measurements are taken with a high-density optode montage and provide accurate spatial and temporal information. We found that two pulse parameters (pulse relaxation function, PReFx, and pulse rise time, PRT) in the investigated frontotemporal region, correlated with infant's age at recording, indexing cerebrovascular development. Moreover, PRT differentiated infants with and without concurrent IVH (sensitivity = 100%, specificity = 70%). These values are at least as high as those of the resistivity index obtained with transcranial Doppler of the middle cerebral artery, the current clinical method of choice for investigating arterial elasticity in preterm infants. This makes pulse-DOT a promising tool for investigating cerebrovascular risk factors and related pathologies in preterm infants.
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Affiliation(s)
- Antonio M Chiarelli
- Beckman Institute, University of Illinois at Urbana Champaign, Urbana, IL, USA
| | - Mahdi Mahmoudzadeh
- Institut National de la Santé et de la Recherche Médicale (INSERM), GRAMFC, Université de Picardie Jules Verne, Amiens, France
- Service de Réanimation Néonatale, CHU Amiens, Amiens, France
| | - Kathy A Low
- Beckman Institute, University of Illinois at Urbana Champaign, Urbana, IL, USA
| | - Edward L Maclin
- Beckman Institute, University of Illinois at Urbana Champaign, Urbana, IL, USA
| | - Guy Kongolo
- Institut National de la Santé et de la Recherche Médicale (INSERM), GRAMFC, Université de Picardie Jules Verne, Amiens, France
- Service de Réanimation Néonatale, CHU Amiens, Amiens, France
| | - Sabrina Goudjil
- Institut National de la Santé et de la Recherche Médicale (INSERM), GRAMFC, Université de Picardie Jules Verne, Amiens, France
- Service de Réanimation Néonatale, CHU Amiens, Amiens, France
| | - Monica Fabiani
- Beckman Institute, University of Illinois at Urbana Champaign, Urbana, IL, USA
- Psychology Department, University of Illinois at Urbana Champaign, Champaign, IL, USA
| | - Fabrice Wallois
- Institut National de la Santé et de la Recherche Médicale (INSERM), GRAMFC, Université de Picardie Jules Verne, Amiens, France
- Service d’Explorations Fonctionnelles du Système Nerveux Pédiatrique, CHU Amiens, Amiens, France
| | - Gabriele Gratton
- Beckman Institute, University of Illinois at Urbana Champaign, Urbana, IL, USA
- Psychology Department, University of Illinois at Urbana Champaign, Champaign, IL, USA
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23
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Ulrich L, Ahnen L, Akarçay HG, Majos SS, Jaeger M, Held KG, Wolf M, Frenz M. Spectral correction for handheld optoacoustic imaging by means of near-infrared optical tomography in reflection mode. JOURNAL OF BIOPHOTONICS 2019; 12:e201800112. [PMID: 30098119 PMCID: PMC7065640 DOI: 10.1002/jbio.201800112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 07/24/2018] [Accepted: 08/09/2018] [Indexed: 05/04/2023]
Abstract
In vivo imaging of tissue/vasculature oxygen saturation levels is of prime interest in many clinical applications. To this end, the feasibility of combining two distinct and complementary imaging modalities is investigated: optoacoustics (OA) and near-infrared optical tomography (NIROT), both operating noninvasively in reflection mode. Experiments were conducted on two optically heterogeneous phantoms mimicking tissue before and after the occurrence of a perturbation. OA imaging was used to resolve submillimetric vessel-like optical absorbers at depths up to 25 mm, but with a spectral distortion in the OA signals. NIROT measurements were utilized to image perturbations in the background and to estimate the light fluence inside the phantoms at the wavelength pair (760 nm, 830 nm). This enabled the spectral correction of the vessel-like absorbers' OA signals: the error in the ratio of the absorption coefficient at 830 nm to that at 760 nm was reduced from 60%-150% to 10%-20%. The results suggest that oxygen saturation (SO 2 ) levels in arteries can be determined with <10% error and furthermore, that relative changes in vessels' SO 2 can be monitored with even better accuracy. The outcome relies on a proper identification of the OA signals emanating from the studied vessels.
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Affiliation(s)
- Leonie Ulrich
- Institute of Applied PhysicsUniversity of BernBernSwitzerland
| | - Linda Ahnen
- Biomedical Optics Research Laboratory, Department of NeonatologyUniversity Hospital ZurichZurichSwitzerland
| | | | - Salvador Sánchez Majos
- Biomedical Optics Research Laboratory, Department of NeonatologyUniversity Hospital ZurichZurichSwitzerland
| | - Michael Jaeger
- Institute of Applied PhysicsUniversity of BernBernSwitzerland
| | - Kai Gerrit Held
- Institute of Applied PhysicsUniversity of BernBernSwitzerland
| | - Martin Wolf
- Biomedical Optics Research Laboratory, Department of NeonatologyUniversity Hospital ZurichZurichSwitzerland
| | - Martin Frenz
- Institute of Applied PhysicsUniversity of BernBernSwitzerland
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Tremblay J, Martínez-Montes E, Vannasing P, Nguyen DK, Sawan M, Lepore F, Gallagher A. Comparison of source localization techniques in diffuse optical tomography for fNIRS application using a realistic head model. BIOMEDICAL OPTICS EXPRESS 2018; 9:2994-3016. [PMID: 30619642 PMCID: PMC6033567 DOI: 10.1364/boe.9.002994] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 05/18/2018] [Accepted: 05/26/2018] [Indexed: 05/24/2023]
Abstract
Functional near-infrared spectroscopy (fNIRS) is a non-invasive imaging technique that elicits growing interest for research and clinical applications. In the last decade, efforts have been made to develop a mathematical framework in order to image the effective sources of hemoglobin variations in brain tissues. Different approaches can be used to impose additional information or constraints when reconstructing the cerebral images of an ill-posed problem. The goal of this study is to compare the performance and limitations of several source localization techniques in the context of fNIRS tomography using individual anatomical magnetic resonance imaging (MRI) to model light propagation. The forward problem is solved using a Monte Carlo simulation of light propagation in the tissues. The inverse problem has been linearized using the Rytov approximation. Then, Tikhonov regularization applied to least squares, truncated singular value decomposition, back-projection, L1-norm regularization, minimum norm estimates, low resolution electromagnetic tomography and Bayesian model averaging techniques are compared using a receiver operating characteristic analysis, blurring and localization error measures. Using realistic simulations (n = 450) and data acquired from a human participant, this study depicts how these source localization techniques behave in a human head fNIRS tomography. When compared to other methods, Bayesian model averaging is proposed as a promising method in DOT and shows great potential to improve specificity, accuracy, as well as to reduce blurring and localization error even in presence of noise and deep sources. Classical reconstruction methods, such as regularized least squares, offer better sensitivity but higher blurring; while more novel L1-based method provides sparse solutions with small blurring and high specificity but lower sensitivity. The application of these methods is also demonstrated experimentally using visual fNIRS experiment with adult participant.
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Affiliation(s)
- Julie Tremblay
- LIONLAB, Centre de recherche du CHU Sainte-Justine, Université de Montréal, Montréal, Canada
| | | | - Phetsamone Vannasing
- LIONLAB, Centre de recherche du CHU Sainte-Justine, Université de Montréal, Montréal, Canada
| | - Dang K Nguyen
- Neurology Division, Centre hospitalier de l'Université de Montréal (CHUM), Hôpital Notre-Dame, Montréal, Canada
| | - Mohamad Sawan
- Polystim Neurotech Lab, Polytechnique Montréal, Montréal, Canada
| | - Franco Lepore
- Centre de recherche en neuropsychologie et cognition (CERNEC), Département de psychologie, Université de Montréal, Montréal, Canada
| | - Anne Gallagher
- LIONLAB, Centre de recherche du CHU Sainte-Justine, Université de Montréal, Montréal, Canada
- Centre de recherche en neuropsychologie et cognition (CERNEC), Département de psychologie, Université de Montréal, Montréal, Canada
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25
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Xu K, Shi J, Pourmand A, Udayakumar TS, Dogan N, Zhao W, Pollack A, Yang Y. Plasmonic Optical Imaging of Gold Nanorods Localization in Small Animals. Sci Rep 2018; 8:9342. [PMID: 29921960 PMCID: PMC6008467 DOI: 10.1038/s41598-018-27624-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 06/04/2018] [Indexed: 12/22/2022] Open
Abstract
Gold nanoparticles (GNP) have been intensively investigated for applications in cancer imaging and therapy. Most imaging studies focused on microscopic imaging. Their potential as optical imaging probes for whole body small animal imaging has rarely been explored. Taking advantage of their surface plasmon resonance (SPR) properties, we aim to develop a noninvasive diffuse optical imaging method to map the distribution of a special type of GNP, gold nanorods (GNR), in small animals. We developed an integrated dual-modality imaging system capable of both x-ray computed tomography (XCT) and diffuse optical tomography (DOT). XCT provides the animal anatomy and contour required for DOT; DOT maps the distribution of GNR in the animal. This SPR enhanced optical imaging (SPROI) technique was investigated using simulation, phantom and mouse experiments. The distribution of GNR at various concentrations (0.1-100 nM, or 3.5 ug/g-3.5 mg/g) was successfully reconstructed from centimeter-scaled volumes. SPROI detected GNR at 18 μg/g concentration in the mouse breast tumor, and is 3 orders more sensitive than x-ray imaging. This study demonstrated the high sensitivity of SPROI in mapping GNR distributions in small animals. It does not require additional imaging tags other than GNR themselves. SPROI can be used to detect tumors targeted by GNR via passive targeting based on enhanced permeability and retention or via active targeting using biologically conjugated ligands.
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Affiliation(s)
- Keying Xu
- Department of Radiation Oncology, University of Miami School of Medicine, Miami, FL, 33136, USA
- Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, 33146, USA
| | - Junwei Shi
- Department of Radiation Oncology, University of Miami School of Medicine, Miami, FL, 33136, USA
| | - Ali Pourmand
- Department of Marine Geoscience, University of Miami RSMAS, Miami, FL, 33149, USA
| | | | - Nesrin Dogan
- Department of Radiation Oncology, University of Miami School of Medicine, Miami, FL, 33136, USA
- Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, 33146, USA
| | - Weizhao Zhao
- Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, 33146, USA
| | - Alan Pollack
- Department of Radiation Oncology, University of Miami School of Medicine, Miami, FL, 33136, USA
| | - Yidong Yang
- Department of Radiation Oncology, University of Miami School of Medicine, Miami, FL, 33136, USA.
- Department of Biomedical Engineering, University of Miami College of Engineering, Coral Gables, FL, 33146, USA.
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26
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Alayed M, Naser MA, Aden-Ali I, Deen MJ. Time-resolved diffuse optical tomography system using an accelerated inverse problem solver. OPTICS EXPRESS 2018; 26:963-979. [PMID: 29401984 DOI: 10.1364/oe.26.000963] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
A computationally efficient time-resolved diffuse optical tomography (TR-DOT) prototype was demonstrated using an accelerated inverse problem solver to reconstruct high quality 3D images of highly scattering media such as tissues. The inverse problem solver utilizes seven well-defined points on each experimentally recorded histogram of the distribution time-of-flight (DToF). In this work, the accuracy of the recovered optical properties, and the computational load and time of TR-DOT prototype were investigated using cylindrical turbid phantoms. These phantoms were measured using transmittance geometry under different conditions in multiple experiments to evaluate the performance of this prototype. Overall, the results of evaluation are important in the realization of a real-time and highly accurate TR-DOT system for diffuse optical imaging applications.
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Uddin KMS, Mostafa A, Anastasio M, Zhu Q. Two step imaging reconstruction using truncated pseudoinverse as a preliminary estimate in ultrasound guided diffuse optical tomography. BIOMEDICAL OPTICS EXPRESS 2017; 8:5437-5449. [PMID: 29296479 PMCID: PMC5745094 DOI: 10.1364/boe.8.005437] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 10/15/2017] [Accepted: 10/19/2017] [Indexed: 05/18/2023]
Abstract
Due to the correlated nature of diffused light, the problem of reconstructing optical properties using diffuse optical tomography (DOT) is ill-posed. US-, MRI- or x-ray-guided DOT approaches can reduce the total number of parameters to be estimated and improve optical reconstruction accuracy. However, when the target volume is large, the number of parameters to estimate can exceed the number of measurements, resulting in an underdetermined imaging model. In such cases, accurate image reconstruction is difficult and regularization methods should be employed to obtain a useful solution. In this manuscript, a simple two-step reconstruction method that can produce useful image estimates in DOT is proposed and investigated. In the first step, a truncated Moore-Penrose Pseudoinverse solution is computed to obtain a preliminary estimate of the image that can be reliably determined from the measured data; subsequently, this preliminary estimate is incorporated into the design of a penalized least squares estimator that is employed to compute the final image estimate. By use of phantom data, the proposed method was demonstrated to yield more accurate images than those produced by conventional reconstruction methods. The method was also evaluated with clinical data that included 10 benign and 10 malignant cases. The capability of reconstructing high contrast malignant lesions was demonstrated to be improved by use of the proposed method.
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28
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Luk A, Nouizi F, Erkol H, Unlu MB, Gulsen G. Ex vivo validation of photo-magnetic imaging. OPTICS LETTERS 2017; 42:4171-4174. [PMID: 29028040 PMCID: PMC6855589 DOI: 10.1364/ol.42.004171] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 09/14/2017] [Indexed: 05/18/2023]
Abstract
We recently introduced a new high-resolution diffuse optical imaging technique termed photo-magnetic imaging (PMI), which utilizes magnetic resonance thermometry (MRT) to monitor the 3D temperature distribution induced in a medium illuminated with a near-infrared light. The spatiotemporal temperature distribution due to light absorption can be accurately estimated using a combined photon propagation and heat diffusion model. High-resolution optical absorption images are then obtained by iteratively minimizing the error between the measured and modeled temperature distributions. We have previously demonstrated the feasibility of PMI with experimental studies using tissue simulating agarose phantoms. In this Letter, we present the preliminary ex vivo PMI results obtained with a chicken breast sample. Similarly to the results obtained on phantoms, the reconstructed images reveal that PMI can quantitatively resolve an inclusion with a 3 mm diameter embedded deep in a biological tissue sample with only 10% error. These encouraging results demonstrate the high performance of PMI in ex vivo biological tissue and its potential for in vivo imaging.
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Affiliation(s)
- Alex Luk
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
| | - Farouk Nouizi
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
| | - Hakan Erkol
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
| | - Mehmet B. Unlu
- Department of Physics, Bogazici University, Bebek, Istanbul, Turkey
| | - Gultekin Gulsen
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
- Department of Biomedical Engineering, University of California, Irvine, California 92697, USA
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29
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Time-Resolved Diffuse Optical Spectroscopy and Imaging Using Solid-State Detectors: Characteristics, Present Status, and Research Challenges. SENSORS 2017; 17:s17092115. [PMID: 28906462 PMCID: PMC5621067 DOI: 10.3390/s17092115] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 09/03/2017] [Accepted: 09/06/2017] [Indexed: 02/06/2023]
Abstract
Diffuse optical spectroscopy (DOS) and diffuse optical imaging (DOI) are emerging non-invasive imaging modalities that have wide spread potential applications in many fields, particularly for structural and functional imaging in medicine. In this article, we review time-resolved diffuse optical imaging (TR-DOI) systems using solid-state detectors with a special focus on Single-Photon Avalanche Diodes (SPADs) and Silicon Photomultipliers (SiPMs). These TR-DOI systems can be categorized into two types based on the operation mode of the detector (free-running or time-gated). For the TR-DOI prototypes, the physical concepts, main components, figures-of-merit of detectors, and evaluation parameters are described. The performance of TR-DOI prototypes is evaluated according to the parameters used in common protocols to test DOI systems particularly basic instrumental performance (BIP). In addition, the potential features of SPADs and SiPMs to improve TR-DOI systems and expand their applications in the foreseeable future are discussed. Lastly, research challenges and future developments for TR-DOI are discussed for each component in the prototype separately and also for the entire system.
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Cong W, Intes X, Wang G. Optical tomographic imaging for breast cancer detection. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:1-6. [PMID: 28933069 PMCID: PMC5605673 DOI: 10.1117/1.jbo.22.9.096011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 08/21/2017] [Indexed: 06/07/2023]
Abstract
Diffuse optical breast imaging utilizes near-infrared (NIR) light propagation through tissues to assess the optical properties of tissues for the identification of abnormal tissue. This optical imaging approach is sensitive, cost-effective, and does not involve any ionizing radiation. However, the image reconstruction of diffuse optical tomography (DOT) is a nonlinear inverse problem and suffers from severe illposedness due to data noise, NIR light scattering, and measurement incompleteness. An image reconstruction method is proposed for the detection of breast cancer. This method splits the image reconstruction problem into the localization of abnormal tissues and quantification of absorption variations. The localization of abnormal tissues is performed based on a well-posed optimization model, which can be solved via a differential evolution optimization method to achieve a stable reconstruction. The quantification of abnormal absorption is then determined in localized regions of relatively small extents, in which a potential tumor might be. Consequently, the number of unknown absorption variables can be greatly reduced to overcome the underdetermined nature of DOT. Numerical simulation experiments are performed to verify merits of the proposed method, and the results show that the image reconstruction method is stable and accurate for the identification of abnormal tissues, and robust against the measurement noise of data.
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Affiliation(s)
- Wenxiang Cong
- Rensselaer Polytechnic Institute, Biomedical Imaging Center, Department of Biomedical Engineering, Troy, New York, United States
| | - Xavier Intes
- Rensselaer Polytechnic Institute, Biomedical Imaging Center, Department of Biomedical Engineering, Troy, New York, United States
| | - Ge Wang
- Rensselaer Polytechnic Institute, Biomedical Imaging Center, Department of Biomedical Engineering, Troy, New York, United States
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Collagen Complexity Spatially Defines Microregions of Total Tissue Pressure in Pancreatic Cancer. Sci Rep 2017; 7:10093. [PMID: 28855644 PMCID: PMC5577321 DOI: 10.1038/s41598-017-10671-w] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 08/11/2017] [Indexed: 12/18/2022] Open
Abstract
The poor efficacy of systemic cancer therapeutics in pancreatic ductal adenocarcinoma (PDAC) is partly attributed to deposition of collagen and hyaluronan, leading to interstitial hypertension collapsing blood and lymphatic vessels, limiting drug delivery. The intrinsic micro-regional interactions between hyaluronic acid (HA), collagen and the spatial origins of mechanical stresses that close off blood vessels was investigated here. Multiple localized pressure measurements were analyzed with spatially-matched histochemical images of HA, collagen and vessel perfusion. HA is known to swell, fitting a linear elastic model with total tissue pressure (TTP) increasing above interstitial fluid pressure (IFP) directly with collagen content. However, local TTP appears to originate from collagen area fraction, as well as increased its entropy and fractal dimension, and morphologically appears to be maximized when HA regions are encapsulated by collagen. TTP was inversely correlated with vascular patency and verteporfin uptake, suggesting interstitial hypertension results in vascular compression and decreased molecular delivery in PDAC. Collagenase injection led to acute decreases in total tissue pressure and increased drug perfusion. Large microscopic variations in collagen distributions within PDAC leads to microregional TPP values that vary on the hundred micron distance scale, causing micro-heterogeneous limitations in molecular perfusion, and narrows viable treatment regimes for systemically delivered therapeutics.
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Weersink RA, Chaudhary S, Mayo K, He J, Wilson BC. Shape-based reconstruction for transrectal diffuse optical tomography monitoring of photothermal focal therapy of prostate cancer: simulation studies. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:45004. [PMID: 28384707 DOI: 10.1117/1.jbo.22.4.045004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 03/17/2017] [Indexed: 06/07/2023]
Abstract
We develop and demonstrate a simple shape-based approach for diffuse optical tomographic reconstruction of coagulative lesions generated during interstitial photothermal therapy (PTT) of the prostate. The shape-based reconstruction assumes a simple ellipsoid shape, matching the general dimensions of a cylindrical diffusing fiber used for light delivery in current clinical studies of PTT in focal prostate cancer. The specific requirement is to accurately define the border between the photothermal lesion and native tissue as the photothermal lesion grows, with an accuracy of ? 1 ?? mm , so treatment can be terminated before there is damage to the rectal wall. To demonstrate the feasibility of the shape-based diffuse optical tomography reconstruction, simulated data were generated based on forward calculations in known geometries that include the prostate, rectum, and lesions of varying dimensions. The only source of optical contrast between the lesion and prostate was increased scattering in the lesion, as is typically observed with coagulation. With noise added to these forward calculations, lesion dimensions were reconstructed using the shape-based method. This approach for reconstruction is shown to be feasible and sufficiently accurate for lesions that are within 4 mm from the rectal wall. The method was also robust for irregularly shaped lesions.
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Affiliation(s)
- Robert A Weersink
- University of Toronto, Department of Radiation Oncology, Toronto, Ontario, CanadabUniversity of Toronto, Institute of Biomaterials and Biomedical Engineering, Toronto, Ontario, CanadacUniversity Health Network, Techna Institute, Toronto, Ontario, CanadadUniversity Health Network, Radiation Medicine Program, Toronto, Ontario, Canada
| | - Sahil Chaudhary
- University of Toronto, Department of Medical Biophysics, Toronto, Ontario, Canada
| | - Kenwrick Mayo
- University of Toronto, Department of Medical Biophysics, Toronto, Ontario, Canada
| | - Jie He
- University of Toronto, Department of Medical Biophysics, Toronto, Ontario, Canada
| | - Brian C Wilson
- University Health Network, Techna Institute, Toronto, Ontario, CanadaeUniversity of Toronto, Department of Medical Biophysics, Toronto, Ontario, CanadafUniversity Health Network, Ontario Cancer Institute, Toronto, Ontario, Canada
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Reisman MD, Markow ZE, Bauer AQ, Culver JP. Structured illumination diffuse optical tomography for noninvasive functional neuroimaging in mice. NEUROPHOTONICS 2017; 4:021102. [PMID: 28439519 PMCID: PMC5391480 DOI: 10.1117/1.nph.4.2.021102] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 02/01/2017] [Indexed: 05/15/2023]
Abstract
Optical intrinsic signal (OIS) imaging has been a powerful tool for capturing functional brain hemodynamics in rodents. Recent wide field-of-view implementations of OIS have provided efficient maps of functional connectivity from spontaneous brain activity in mice. However, OIS requires scalp retraction and is limited to superficial cortical tissues. Diffuse optical tomography (DOT) techniques provide noninvasive imaging, but previous DOT systems for rodent neuroimaging have been limited either by sparse spatial sampling or by slow speed. Here, we develop a DOT system with asymmetric source-detector sampling that combines the high-density spatial sampling (0.4 mm) detection of a scientific complementary metal-oxide-semiconductor camera with the rapid (2 Hz) imaging of a few ([Formula: see text]) structured illumination (SI) patterns. Analysis techniques are developed to take advantage of the system's flexibility and optimize trade-offs among spatial sampling, imaging speed, and signal-to-noise ratio. An effective source-detector separation for the SI patterns was developed and compared with light intensity for a quantitative assessment of data quality. The light fall-off versus effective distance was also used for in situ empirical optimization of our light model. We demonstrated the feasibility of this technique by noninvasively mapping the functional response in the somatosensory cortex of the mouse following electrical stimulation of the forepaw.
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Affiliation(s)
- Matthew D. Reisman
- Washington University in St. Louis, Department of Physics, St. Louis, Missouri, United States
| | - Zachary E. Markow
- Washington University in St. Louis, Department of Biomedical Engineering, St. Louis, Missouri, United States
| | - Adam Q. Bauer
- Washington University School of Medicine, Department of Radiology, St. Louis, Missouri, United States
| | - Joseph P. Culver
- Washington University in St. Louis, Department of Physics, St. Louis, Missouri, United States
- Washington University in St. Louis, Department of Biomedical Engineering, St. Louis, Missouri, United States
- Washington University School of Medicine, Department of Radiology, St. Louis, Missouri, United States
- Address all correspondence to: Joseph P. Culver, E-mail:
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Wan W, Wang Y, Qi J, Liu L, Ma W, Li J, Zhang L, Zhou Z, Zhao H, Gao F. Region-based diffuse optical tomography with registered atlas: in vivo acquisition of mouse optical properties. BIOMEDICAL OPTICS EXPRESS 2016; 7:5066-5080. [PMID: 28018725 PMCID: PMC5175552 DOI: 10.1364/boe.7.005066] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 10/20/2016] [Accepted: 11/09/2016] [Indexed: 05/14/2023]
Abstract
The reconstruction quality in the model-based optical tomography modalities can greatly benefit from a priori information of accurate tissue optical properties, which are difficult to be obtained in vivo with a conventional diffuse optical tomography (DOT) system alone. One of the solutions is to apply a priori anatomical structures obtained with anatomical imaging systems such as X-ray computed tomography (XCT) to constrain the reconstruction process of DOT. However, since X-ray offers low soft-tissue contrast, segmentation of abdominal organs from sole XCT images can be problematic. In order to overcome the challenges, the current study proposes a novel method of recovering a priori organ-oriented tissue optical properties, where anatomical structures of an in vivo mouse are approximately obtained by registering a standard anatomical atlas, i.e., the Digimouse, to the target XCT volume with the non-rigid image registration, and, in turn, employed to guide DOT for extracting the optical properties of inner organs. Simulative investigations have validated the methodological availability of such atlas-registration-based DOT strategy in revealing both a priori anatomical structures and optical properties. Further experiments have demonstrated the feasibility of the proposed method for acquiring the organ-oriented tissue optical properties of in vivo mice, making it as an efficient way of the reconstruction enhancement.
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Affiliation(s)
- Wenbo Wan
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Yihan Wang
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Jin Qi
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Cancer Institute and Hospital, Tianjin Medical University, Tianjin 300060, China
| | - Lingling Liu
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Wenjuan Ma
- Cancer Institute and Hospital, Tianjin Medical University, Tianjin 300060, China
| | - Jiao Li
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
| | - Limin Zhang
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
| | - Zhongxing Zhou
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
| | - Huijuan Zhao
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
| | - Feng Gao
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
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Wu HY, Filer A, Styles I, Dehghani H. Development of a multi-wavelength diffuse optical tomography system for early diagnosis of rheumatoid arthritis: simulation, phantoms and healthy human studies. BIOMEDICAL OPTICS EXPRESS 2016; 7:4769-4786. [PMID: 27896015 PMCID: PMC5119615 DOI: 10.1364/boe.7.004769] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Revised: 06/30/2016] [Accepted: 07/22/2016] [Indexed: 05/21/2023]
Abstract
A multi-wavelength diffuse optical tomography (DOT) system has been developed to directly extract physiological information, such as total haemoglobin concentration, from tissue in human hand joints. Novel methods for 3D surface imaging and spectrally constrained image reconstruction are introduced and their potential application to imaging of rheumatoid arthritis is discussed. Results are presented from simulation studies as well as experiments using phantoms and data from imaging of three healthy volunteers. The image features are recovered partially for phantom data using transmission measurements only. Images that reveal joint regions and surrounding features within the hand are shown to co-register with co-acquired ultrasound images which are shown to be related to total haemoglobin concentration.
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Affiliation(s)
- Hao Yang Wu
- The Centre for Physical Sciences of Imaging in Biomedical Sciences (PSIBS), University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Andrew Filer
- The Rheumatology Research Group, School of Immunity and Infection, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Iain Styles
- The Centre for Physical Sciences of Imaging in Biomedical Sciences (PSIBS), University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
- School of Computer Science, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Hamid Dehghani
- The Centre for Physical Sciences of Imaging in Biomedical Sciences (PSIBS), University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
- School of Computer Science, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
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Nouizi F, Erkol H, Luk A, Marks M, Unlu MB, Gulsen G. An accelerated photo-magnetic imaging reconstruction algorithm based on an analytical forward solution and a fast Jacobian assembly method. Phys Med Biol 2016; 61:7448-7465. [PMID: 27694717 DOI: 10.1088/0031-9155/61/20/7448] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We previously introduced photo-magnetic imaging (PMI), an imaging technique that illuminates the medium under investigation with near-infrared light and measures the induced temperature increase using magnetic resonance thermometry (MRT). Using a multiphysics solver combining photon migration and heat diffusion, PMI models the spatiotemporal distribution of temperature variation and recovers high resolution optical absorption images using these temperature maps. In this paper, we present a new fast non-iterative reconstruction algorithm for PMI. This new algorithm uses analytic methods during the resolution of the forward problem and the assembly of the sensitivity matrix. We validate our new analytic-based algorithm with the first generation finite element method (FEM) based reconstruction algorithm previously developed by our team. The validation is performed using, first synthetic data and afterwards, real MRT measured temperature maps. Our new method accelerates the reconstruction process 30-fold when compared to a single iteration of the FEM-based algorithm.
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Affiliation(s)
- F Nouizi
- Department of Radiological Sciences, Tu and Yuen Center for Functional Onco-Imaging, University of California, Irvine, CA, USA
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Nouizi F, Erkol H, Luk A, Unlu MB, Gulsen G. Real-time photo-magnetic imaging. BIOMEDICAL OPTICS EXPRESS 2016; 7:3899-3904. [PMID: 27867701 PMCID: PMC5102518 DOI: 10.1364/boe.7.003899] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 08/07/2016] [Accepted: 08/08/2016] [Indexed: 05/25/2023]
Abstract
We previously introduced a new high resolution diffuse optical imaging modality termed, photo-magnetic imaging (PMI). PMI irradiates the object under investigation with near-infrared light and monitors the variations of temperature using magnetic resonance thermometry (MRT). In this paper, we present a real-time PMI image reconstruction algorithm that uses analytic methods to solve the forward problem and assemble the Jacobian matrix much faster. The new algorithm is validated using real MRT measured temperature maps. In fact, it accelerates the reconstruction process by more than 250 times compared to a single iteration of the FEM-based algorithm, which opens the possibility for the real-time PMI.
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Affiliation(s)
- Farouk Nouizi
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, CA, USA
| | - Hakan Erkol
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, CA, USA
- Department of Physics, Bogazici University, Bebek, 34342, Istanbul, Turkey
| | - Alex Luk
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, CA, USA
- Department of Biomedical Engineering, University of California, Irvine, CA, USA
| | - Mehmet B. Unlu
- Department of Physics, Bogazici University, Bebek, 34342, Istanbul, Turkey
| | - Gultekin Gulsen
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, CA, USA
- Department of Biomedical Engineering, University of California, Irvine, CA, USA
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38
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Vavadi H, Zhu Q. Automated data selection method to improve robustness of diffuse optical tomography for breast cancer imaging. BIOMEDICAL OPTICS EXPRESS 2016; 7:4007-4020. [PMID: 27867711 PMCID: PMC5102542 DOI: 10.1364/boe.7.004007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/16/2016] [Accepted: 09/03/2016] [Indexed: 05/18/2023]
Abstract
Imaging-guided near infrared diffuse optical tomography (DOT) has demonstrated a great potential as an adjunct modality for differentiation of malignant and benign breast lesions and for monitoring treatment response of breast cancers. However, diffused light measurements are sensitive to artifacts caused by outliers and errors in measurements due to probe-tissue coupling, patient and probe motions, and tissue heterogeneity. In general, pre-processing of the measurements is needed by experienced users to manually remove these outliers and therefore reduce imaging artifacts. An automated method of outlier removal, data selection, and filtering for diffuse optical tomography is introduced in this manuscript. This method consists of multiple steps to first combine several data sets collected from the same patient at contralateral normal breast and form a single robust reference data set using statistical tests and linear fitting of the measurements. The second step improves the perturbation measurements by filtering out outliers from the lesion site measurements using model based analysis. The results of 20 malignant and benign cases show similar performance between manual data processing and automated processing and improvement in tissue characterization of malignant to benign ratio by about 27%.
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Affiliation(s)
- Hamed Vavadi
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT, USA
| | - Quing Zhu
- Department of Biomedical Engineering, Washington University in St. Louis, USA
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39
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Satat G, Heshmat B, Raviv D, Raskar R. All Photons Imaging Through Volumetric Scattering. Sci Rep 2016; 6:33946. [PMID: 27683065 PMCID: PMC5041145 DOI: 10.1038/srep33946] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 09/02/2016] [Indexed: 01/11/2023] Open
Abstract
Imaging through thick highly scattering media (sample thickness ≫ mean free path) can realize broad applications in biomedical and industrial imaging as well as remote sensing. Here we propose a computational "All Photons Imaging" (API) framework that utilizes time-resolved measurement for imaging through thick volumetric scattering by using both early arrived (non-scattered) and diffused photons. As opposed to other methods which aim to lock on specific photons (coherent, ballistic, acoustically modulated, etc.), this framework aims to use all of the optical signal. Compared to conventional early photon measurements for imaging through a 15 mm tissue phantom, our method shows a two fold improvement in spatial resolution (4db increase in Peak SNR). This all optical, calibration-free framework enables widefield imaging through thick turbid media, and opens new avenues in non-invasive testing, analysis, and diagnosis.
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Affiliation(s)
- Guy Satat
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Barmak Heshmat
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Dan Raviv
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ramesh Raskar
- Media Lab, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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Hoshi Y, Yamada Y. Overview of diffuse optical tomography and its clinical applications. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:091312. [PMID: 27420810 DOI: 10.1117/1.jbo.21.9.091312] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 06/13/2016] [Indexed: 05/23/2023]
Abstract
Near-infrared diffuse optical tomography (DOT), one of the most sophisticated optical imaging techniques for observations through biological tissue, allows 3-D quantitative imaging of optical properties, which include functional and anatomical information. With DOT, it is expected to be possible to overcome the limitations of conventional near-infrared spectroscopy (NIRS) as well as offering the potential for diagnostic optical imaging. However, DOT has been under development for more than 30 years, and the difficulties in development are attributed to the fact that light is strongly scattered and that diffusive photons are used for the image reconstruction. The DOT algorithm is based on the techniques of inverse problems. The radiative transfer equation accurately describes photon propagation in biological tissue, while, because of its high computation load, the diffusion equation (DE) is often used as the forward model. However, the DE is invalid in low-scattering and/or highly absorbing regions and in the vicinity of light sources. The inverse problem is inherently ill-posed and highly undetermined. Here, we first summarize NIRS and then describe various approaches in the efforts to develop accurate and efficient DOT algorithms and present some examples of clinical applications. Finally, we discuss the future prospects of DOT.
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Affiliation(s)
- Yoko Hoshi
- Hamamatsu University School of Medicine, Department of Biomedical Optics, Institute for Medical Photonics Research, Preeminent Medical Photonics Education and Research Center, 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Japan
| | - Yukio Yamada
- University of Electro-Communications, Brain Science Inspired Life Support Research Center, 1-5-1 Chofugaoka, Chofu, Tokyo 182-8585, Japan
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Clancy M, Belli A, Davies D, Lucas SJE, Su Z, Dehghani H. Improving the quantitative accuracy of cerebral oxygen saturation in monitoring the injured brain using atlas based Near Infrared Spectroscopy models. JOURNAL OF BIOPHOTONICS 2016; 9:812-826. [PMID: 27003677 DOI: 10.1002/jbio.201500302] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 02/18/2016] [Accepted: 02/18/2016] [Indexed: 06/05/2023]
Abstract
The application of Near Infrared Spectroscopy (NIRS) for the monitoring of the cerebral oxygen saturation within the brain is well established, albeit using temporal data that can only measure relative changes of oxygenation state of the brain from a baseline. The focus of this investigation is to demonstrate that hybridisation of existing near infrared probe designs and reconstruction techniques can pave the way to produce a system and methods that can be used to monitor the absolute oxygen saturation in the injured brain. Using registered Atlas models in simulation, a novel method is outlined by which the quantitative accuracy and practicality of NIRS for specific use in monitoring the injured brain, can be improved, with cerebral saturation being recovered to within 10.1 ± 1.8% of the expected values.
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Affiliation(s)
- Michael Clancy
- PSIBS Doctoral Training Centre, University of Birmingham, United Kingdom.
| | - Antonio Belli
- NIHR Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital Birmingham, United Kingdom
| | - David Davies
- NIHR Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital Birmingham, United Kingdom
| | - Samuel J E Lucas
- School of Sport, Exercise and Rehabilitation Science, University of Birmingham, United Kingdom
| | - Zhangjie Su
- NIHR Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital Birmingham, United Kingdom
| | - Hamid Dehghani
- School of Computer Science, University of Birmingham, United Kingdom
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Bhatt M, Ayyalasomayajula KR, Yalavarthy PK. Generalized Beer-Lambert model for near-infrared light propagation in thick biological tissues. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:76012. [PMID: 27436050 DOI: 10.1117/1.jbo.21.7.076012] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 06/20/2016] [Indexed: 05/08/2023]
Abstract
The attenuation of near-infrared (NIR) light intensity as it propagates in a turbid medium like biological tissue is described by modified the Beer–Lambert law (MBLL). The MBLL is generally used to quantify the changes in tissue chromophore concentrations for NIR spectroscopic data analysis. Even though MBLL is effective in terms of providing qualitative comparison, it suffers from its applicability across tissue types and tissue dimensions. In this work, we introduce Lambert-W function-based modeling for light propagation in biological tissues, which is a generalized version of the Beer–Lambert model. The proposed modeling provides parametrization of tissue properties, which includes two attenuation coefficients μ0 and η. We validated our model against the Monte Carlo simulation, which is the gold standard for modeling NIR light propagation in biological tissue. We included numerous human and animal tissues to validate the proposed empirical model, including an inhomogeneous adult human head model. The proposed model, which has a closed form (analytical), is first of its kind in providing accurate modeling of NIR light propagation in biological tissues.
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Affiliation(s)
- Manish Bhatt
- Indian Institute of Science, Medical Imaging Group, Department of Computational and Data Sciences, C V Raman Avenue, Bengaluru 560012, India
| | | | - Phaneendra K Yalavarthy
- Indian Institute of Science, Medical Imaging Group, Department of Computational and Data Sciences, C V Raman Avenue, Bengaluru 560012, India
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43
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Towards monitoring dysplastic progression in the oral cavity using a hybrid fiber-bundle imaging and spectroscopy probe. Sci Rep 2016; 6:26734. [PMID: 27220821 PMCID: PMC4879668 DOI: 10.1038/srep26734] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Accepted: 05/06/2016] [Indexed: 02/06/2023] Open
Abstract
Intraepithelial dysplasia of the oral mucosa typically originates in the proliferative cell layer at the basement membrane and extends to the upper epithelial layers as the disease progresses. Detection of malignancies typically occurs upon visual inspection by non-specialists at a late-stage. In this manuscript, we validate a quantitative hybrid imaging and spectroscopy microendoscope to monitor dysplastic progression within the oral cavity microenvironment in a phantom and pre-clinical study. We use an empirical model to quantify optical properties and sampling depth from sub-diffuse reflectance spectra (450–750 nm) at two source-detector separations (374 and 730 μm). Average errors in recovering reduced scattering (5–26 cm−1) and absorption coefficients (0–10 cm−1) in hemoglobin-based phantoms were approximately 2% and 6%, respectively. Next, a 300 μm-thick phantom tumor model was used to validate the probe’s ability to monitor progression of a proliferating optical heterogeneity. Finally, the technique was demonstrated on 13 healthy volunteers and volume-averaged optical coefficients, scattering exponent, hemoglobin concentration, oxygen saturation, and sampling depth are presented alongside a high-resolution microendoscopy image of oral mucosa from one volunteer. This multimodal microendoscopy approach encompasses both structural and spectroscopic reporters of perfusion within the tissue microenvironment and can potentially be used to monitor tumor response to therapy.
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Tran WT, Childs C, Chin L, Slodkowska E, Sannachi L, Tadayyon H, Watkins E, Wong SL, Curpen B, Kaffas AE, Al-Mahrouki A, Sadeghi-Naini A, Czarnota GJ. Multiparametric monitoring of chemotherapy treatment response in locally advanced breast cancer using quantitative ultrasound and diffuse optical spectroscopy. Oncotarget 2016; 7:19762-80. [PMID: 26942698 PMCID: PMC4991417 DOI: 10.18632/oncotarget.7844] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 02/05/2016] [Indexed: 11/25/2022] Open
Abstract
PURPOSE This study evaluated pathological response to neoadjuvant chemotherapy using quantitative ultrasound (QUS) and diffuse optical spectroscopy imaging (DOSI) biomarkers in locally advanced breast cancer (LABC). MATERIALS AND METHODS The institution's ethics review board approved this study. Subjects (n = 22) gave written informed consent prior to participating. US and DOSI data were acquired, relative to the start of neoadjuvant chemotherapy, at weeks 0, 1, 4, 8 and preoperatively. QUS parameters including the mid-band fit (MBF), 0-MHz intercept (SI), and the spectral slope (SS) were determined from tumor ultrasound data using spectral analysis. In the same patients, DOSI was used to measure parameters relating to tumor hemoglobin and composition. Discriminant analysis and receiver-operating characteristic (ROC) analysis was used to classify clinical and pathological response during treatment and to estimate the area under the curve (AUC). Additionally, multivariate analysis was carried out for pairwise QUS/DOSI parameter combinations using a logistic regression model. RESULTS Individual QUS and DOSI parameters, including the (SI), oxy-hemoglobin (HbO2), and total hemoglobin (HbT) were significant markers for response after one week of treatment (p < 0.01). Multivariate (pairwise) combinations increased the sensitivity, specificity and AUC at this time; the SI + HbO2 showed a sensitivity/specificity of 100%, and an AUC of 1.0. CONCLUSIONS QUS and DOSI demonstrated potential as coincident markers for treatment response and may potentially facilitate response-guided therapies. Multivariate QUS and DOSI parameters increased the sensitivity and specificity of classifying LABC patients as early as one week after treatment.
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Affiliation(s)
- William T. Tran
- Department of Radiation Oncology, Sunnybrook Hospital, Toronto, Canada
- Centre for Health and Social Care Research, Sheffield Hallam University, Sheffield, UK
| | - Charmaine Childs
- Centre for Health and Social Care Research, Sheffield Hallam University, Sheffield, UK
| | - Lee Chin
- Department of Radiation Oncology, Sunnybrook Hospital, Toronto, Canada
| | | | - Lakshmanan Sannachi
- Department of Radiation Oncology, Sunnybrook Hospital, Toronto, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Hadi Tadayyon
- Department of Radiation Oncology, Sunnybrook Hospital, Toronto, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Elyse Watkins
- Department of Radiation Oncology, Sunnybrook Hospital, Toronto, Canada
| | | | - Belinda Curpen
- Division of Radiology, Sunnybrook Hospital, Toronto, Canada
| | - Ahmed El Kaffas
- Department of Radiation Oncology, Sunnybrook Hospital, Toronto, Canada
| | - Azza Al-Mahrouki
- Department of Radiation Oncology, Sunnybrook Hospital, Toronto, Canada
| | - Ali Sadeghi-Naini
- Department of Radiation Oncology, Sunnybrook Hospital, Toronto, Canada
| | - Gregory J. Czarnota
- Department of Radiation Oncology, University of Toronto, Toronto, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Canada
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Nouizi F, Luk A, Thayer D, Lin Y, Ha S, Gulsen G. Experimental validation of a high-resolution diffuse optical imaging modality: photomagnetic imaging. JOURNAL OF BIOMEDICAL OPTICS 2016; 21:16009. [PMID: 26790644 PMCID: PMC4719037 DOI: 10.1117/1.jbo.21.1.016009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 12/11/2015] [Indexed: 05/25/2023]
Abstract
We present experimental results that validate our imaging technique termed photomagnetic imaging (PMI). PMI illuminates the medium under investigation with a near-infrared light and measures the induced temperature increase using magnetic resonance imaging. A multiphysics solver combining light and heat propagation is used to model spatiotemporal distribution of temperature increase. Furthermore, a dedicated PMI reconstruction algorithm has been developed to reveal high-resolution optical absorption maps from temperature measurements. Being able to perform measurements at any point within the medium, PMI overcomes the limitations of conventional diffuse optical imaging. We present experimental results obtained on agarose phantoms mimicking biological tissue with inclusions having either different sizes or absorption contrasts, located at various depths. The reconstructed images show that PMI can successfully resolve these inclusions with high resolution and recover their absorption coefficient with high-quantitative accuracy. Even a 1-mm inclusion located 6-mm deep is recovered successfully and its absorption coefficient is underestimated by only 32%. The improved PMI system presented here successfully operates under the maximum skin exposure limits defined by the American National Standards Institute, which opens up the exciting possibility of its future clinical use for diagnostic purposes.
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Affiliation(s)
- Farouk Nouizi
- University of California, Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, 164 Irvine Hall, Irvine, California, United States
| | - Alex Luk
- University of California, Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, 164 Irvine Hall, Irvine, California, United States
| | - Dave Thayer
- University of California, Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, 164 Irvine Hall, Irvine, California, United States
- Washington University in St. Louis, Mallinckrodt Institute of Radiology, 510 South Kingshighway Boulevard, St. Louis, Missouri 63110, United States
| | - Yuting Lin
- University of California, Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, 164 Irvine Hall, Irvine, California, United States
- Massachusetts General Hospital and Harvard Medical School, Department of Radiation Oncology, 55 Fruit Street, Boston, Massachusetts 02144, United States
| | - Seunghoon Ha
- University of California, Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, 164 Irvine Hall, Irvine, California, United States
- Philips Healthcare, N27 West 23676 Paul Road, Pewaukee, Wisconsin 53072, United States
| | - Gultekin Gulsen
- University of California, Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, 164 Irvine Hall, Irvine, California, United States
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Brigadoi S, Powell S, Cooper RJ, Dempsey LA, Arridge S, Everdell N, Hebden J, Gibson AP. Evaluating real-time image reconstruction in diffuse optical tomography using physiologically realistic test data. BIOMEDICAL OPTICS EXPRESS 2015; 6:4719-4737. [PMID: 26713189 PMCID: PMC4679249 DOI: 10.1364/boe.6.004719] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 11/01/2015] [Accepted: 11/03/2015] [Indexed: 05/30/2023]
Abstract
In diffuse optical tomography (DOT), real-time image reconstruction of oxy- and deoxy-haemoglobin changes occurring in the brain could give valuable information in clinical care settings. Although non-linear reconstruction techniques could provide more accurate results, their computational burden makes them unsuitable for real-time applications. Linear techniques can be employed under the assumption that the expected change in absorption is small. Several approaches exist, differing primarily in their handling of regularization and the noise statistics. In real experiments, it is impossible to compute the true noise statistics, because of the presence of physiological oscillations in the measured data. This is even more critical in real-time applications, where no off-line filtering and averaging can be performed to reduce the noise level. Therefore, many studies substitute the noise covariance matrix with the identity matrix. In this paper, we examined two questions: does using the noise model with realistic, imperfect data yield an improvement in image quality compared to using the identity matrix; and what is the difference in quality between online and offline reconstructions. Bespoke test data were created using a novel process through which simulated changes in absorption were added to real resting-state DOT data. A realistic multi-layer head model was used as the geometry for the reconstruction. Results validated our assumptions, highlighting the validity of computing the noise statistics from the measured data for online image reconstruction, which was performed at 2 Hz. Our results can be directly extended to a real application where real-time imaging is required.
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Affiliation(s)
- Sabrina Brigadoi
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT,
UK
| | - Samuel Powell
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT,
UK
- Department of Computer Science, University College London, London WC1E 6BT,
UK
| | - Robert J. Cooper
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT,
UK
| | - Laura A. Dempsey
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT,
UK
| | - Simon Arridge
- Department of Computer Science, University College London, London WC1E 6BT,
UK
| | - Nick Everdell
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT,
UK
| | - Jeremy Hebden
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT,
UK
| | - Adam P. Gibson
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT,
UK
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Liao LD, Li ML, Lai HY, Chen YY, Thakor NV. Study of neurovascular coupling functions for transient focal cerebral ischemia in rats using electrocorticography functional photoacoustic microscopy (ECoG-fPAM). ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2013:1799-802. [PMID: 24110058 DOI: 10.1109/embc.2013.6609871] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Recently, the functional photoacoustic microscopy (fPAM) system has been proven to be a reliable imaging technique for measuring the total hemoglobin concentration (HbT), cerebral blood volume (CBV) and hemoglobin oxygen saturation (SO2) in single cerebral blood vessels of rats. In this study, we report for the first time the combination of electrocorticography (ECoG) recordings and fPAM (ECoG-fPAM) to investigate functional hemodynamic changes and neuro-vascular coupling in single cortical arterioles of rats with electrical forepaw stimulation after photothrombotic stroke. Because of the optical focusing nature of our fPAM system, photo-induced ischemic stroke targeting on single cortical arterioles can be easily conducted with simple adaptation. Functional cerebral HbT, CBV and SO2 changes associated with the induced stroke in selected arterioles from the anterior cerebral artery system were imaged with a 36 × 65-µm spatial resolution. The ECoG-fPAM system complements existing imaging techniques and has the potential to offer a favorable tool for explicitly studying cerebral hemodynamics and neuro-vascular coupling in small animal models of photo-induced ischemic stroke.
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He L, Lin Y, Huang C, Irwin D, Szabunio MM, Yu G. Noncontact diffuse correlation tomography of human breast tumor. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:86003. [PMID: 26259706 PMCID: PMC4688914 DOI: 10.1117/1.jbo.20.8.086003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 07/09/2015] [Indexed: 05/19/2023]
Abstract
Our first step to adapt our recently developed noncontact diffuse correlation tomography (ncDCT) system for three-dimensional (3-D) imaging of blood flow distribution in human breast tumors is reported. A commercial 3-D camera was used to obtain breast surface geometry, which was then converted to a solid volume mesh. An ncDCT probe scanned over a region of interest on the mesh surface and the measured boundary data were combined with a finite element framework for 3-D image reconstruction of blood flow distribution. This technique was tested in computer simulations and in vivo human breasts with low-grade carcinoma. Results from computer simulations suggest that relatively high accuracy can be achieved when the entire tumor is within the sensitive region of diffuse light. Image reconstruction with a priori knowledge of the tumor volume and location can significantly improve the accuracy in recovery of tumor blood flow contrasts. In vivo imaging results from two breast carcinomas show higher average blood flow contrasts (5.9- and 10.9-fold) in the tumor regions compared to the surrounding tissues, which are comparable with previous findings using diffuse correlation spectroscopy. The ncDCT system has the potential to image blood flow distributions in soft and vulnerable tissues without distorting tissue hemodynamics
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Affiliation(s)
- Lian He
- University of Kentucky, Department of Biomedical Engineering, 143 Graham Avenue, Lexington, Kentucky 40506, United States
| | - Yu Lin
- University of Kentucky, Department of Biomedical Engineering, 143 Graham Avenue, Lexington, Kentucky 40506, United States
| | - Chong Huang
- University of Kentucky, Department of Biomedical Engineering, 143 Graham Avenue, Lexington, Kentucky 40506, United States
| | - Daniel Irwin
- University of Kentucky, Department of Biomedical Engineering, 143 Graham Avenue, Lexington, Kentucky 40506, United States
| | - Margaret M. Szabunio
- University of Kentucky, Markey Cancer Center, Division of Women’s Radiology, 800 Rose Street, Lexington, Kentucky 40536, United States
| | - Guoqiang Yu
- University of Kentucky, Department of Biomedical Engineering, 143 Graham Avenue, Lexington, Kentucky 40506, United States
- Address all correspondence to: Guoqiang Yu, E-mail:
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Liao LD, Liu YH, Lai HY, Bandla A, Shih YYI, Chen YY, Thakor NV. Rescue of cortical neurovascular functions during the hyperacute phase of ischemia by peripheral sensory stimulation. Neurobiol Dis 2015; 75:53-63. [DOI: 10.1016/j.nbd.2014.12.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 12/07/2014] [Accepted: 12/23/2014] [Indexed: 10/24/2022] Open
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Goyette A, Pichette J, Tremblay MA, Laurence A, Jermyn M, Mok K, Paulsen KD, Roberts DW, Petrecca K, Wilson BC, Leblond F. Sub-diffuse interstitial optical tomography to improve the safety of brain needle biopsies: a proof-of-concept study. OPTICS LETTERS 2015; 40:170-3. [PMID: 25679836 DOI: 10.1364/ol.40.000170] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The extraction of tissue samples during brain needle biopsy can cause life-threatening hemorrhage because of significant blood vessel injury during the procedure. Vessel rupture can have significant consequences for patient health, ranging from transient neurological deficits to death. Here, we present a sub-diffuse optical tomography technique that can be integrated into neurosurgical workflow to detect the presence of blood vessels. A proof-of-concept study performed on a realistic brain tissue phantom is presented and demonstrates that interstitial optical tomography (iOT) can detect several 1 mm diameter high-contrast absorbing objects located <2 mm from the needle.
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