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Gonzalez EA, Bell MAL. Photoacoustic Imaging and Characterization of Bone in Medicine: Overview, Applications, and Outlook. Annu Rev Biomed Eng 2023; 25:207-232. [PMID: 37000966 DOI: 10.1146/annurev-bioeng-081622-025405] [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: 11/19/2023]
Abstract
Photoacoustic techniques have shown promise in identifying molecular changes in bone tissue and visualizing tissue microstructure. This capability represents significant advantages over gold standards (i.e., dual-energy X-ray absorptiometry) for bone evaluation without requiring ionizing radiation. Instead, photoacoustic imaging uses light to penetrate through bone, followed by acoustic pressure generation, resulting in highly sensitive optical absorption contrast in deep biological tissues. This review covers multiple bone-related photoacoustic imaging contributions to clinical applications, spanning bone cancer, joint pathologies, spinal disorders, osteoporosis, bone-related surgical guidance, consolidation monitoring, and transsphenoidal and transcranial imaging. We also present a summary of photoacoustic-based techniques for characterizing biomechanical properties of bone, including temperature, guided waves, spectral parameters, and spectroscopy. We conclude with a future outlook based on the current state of technological developments, recent achievements, and possible new directions.
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Affiliation(s)
- Eduardo A Gonzalez
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
| | - Muyinatu A Lediju Bell
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Electrical and Computer Engineering and Department of Computer Science, Johns Hopkins University, Baltimore, Maryland, USA;
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Jo J, Xu G, Schiopu E, Chamberland D, Gandikota G, Wang X. Imaging of enthesitis by an LED-based photoacoustic system. JOURNAL OF BIOMEDICAL OPTICS 2020; 25:JBO-200274RR. [PMID: 33331148 PMCID: PMC7744251 DOI: 10.1117/1.jbo.25.12.126005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 12/01/2020] [Indexed: 05/03/2023]
Abstract
SIGNIFICANCE One key pathological characteristic of seronegative spondyloarthropathy (SpA) is inflammation at the insertion of tendons and ligaments into the bone (enthesitis). AIM We explore the potential of the emerging photoacoustic (PA) imaging in diagnosis of SpA and review its feasibility in detecting SpA-associated Achilles tendon enthesitis. APPROACH A light-emitting diode (LED)-based PA and ultrasound combined system was employed. The PA images, both along the long and the short axes of each Achilles tendon insertion region, were acquired at 850-nm wavelength, which is sensitive in depicting increased blood volume (i.e., hyperemia). To assess the hyperemia indicating enthesis inflammation, two parameters were quantified in the imaged tendons, including the average intensity and the density of the color pixels in the pseudo-color PA images. Ten SpA patients, all of which met Assessment of SpA International Society (ASAS) criteria for SpA and were found to have Achilles enthesitis by clinical exam according to a board-certified rheumatologist, were included in the study. RESULTS The PA and Doppler ultrasound imaging of Achilles enthesitis resulting from these 10 SpA patients were compared to those from 10 healthy volunteers, leading to statistically significant differences (p < 0.05) in the applied t-tests. CONCLUSIONS This preliminary clinical study suggests that the LED-based PA imaging holds a promise for sensitive and objective assessment of SpA enthesitis in an outpatient setting of the rheumatology clinic.
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Affiliation(s)
- Janggun Jo
- University of Michigan, Department of Biomedical Engineering, Ann Arbor, Michigan, United States
| | - Guan Xu
- University of Michigan, Department of Biomedical Engineering, Ann Arbor, Michigan, United States
- University of Michigan, Department of Ophthalmology and Visual Sciences, Ann Arbor, Michigan, United States
| | - Elena Schiopu
- University of Michigan Medical School, Division of Rheumatology, Department of Internal Medicine, Ann Arbor, Michigan, United States
- Address all correspondence to Elena Schiopu, ; Girish Gandikota, ; Xueding Wang,
| | - David Chamberland
- University of Michigan Medical School, Division of Rheumatology, Department of Internal Medicine, Ann Arbor, Michigan, United States
| | - Girish Gandikota
- University of Michigan Medical School, Department of Radiology, Ann Arbor, Michigan, United States
- Address all correspondence to Elena Schiopu, ; Girish Gandikota, ; Xueding Wang,
| | - Xueding Wang
- University of Michigan, Department of Biomedical Engineering, Ann Arbor, Michigan, United States
- University of Michigan Medical School, Department of Radiology, Ann Arbor, Michigan, United States
- Address all correspondence to Elena Schiopu, ; Girish Gandikota, ; Xueding Wang,
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Multimodal photoacoustic/ultrasonic imaging system: a promising imaging method for the evaluation of disease activity in rheumatoid arthritis. Eur Radiol 2020; 31:3542-3552. [PMID: 33180165 PMCID: PMC8043900 DOI: 10.1007/s00330-020-07353-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 08/16/2020] [Accepted: 09/24/2020] [Indexed: 11/02/2022]
Abstract
OBJECTIVES We aimed to assess the clinical value of multimodal photoacoustic/ultrasound (PA/US) articular imaging scores, a novel imaging method which can reflect the micro-vessels and oxygenation level of inflamed joints of rheumatoid arthritis (RA). METHODS Seven small joints were examined by the PA/US imaging system. A 0-3 scoring system was used to semi-quantify the PA and power-Doppler (PD) signals, and the sums of PA and PD scores (PA-sum and PD-sum scores) of the seven joints were calculated. The relative oxygen saturation (SO2) values of the inflamed joints were measured and classified into 3 PA+SO2 patterns. The correlations between the PA/US imaging scores and the disease activity scores were assessed. RESULTS Thirty-one patients of RA and a total of 217 joints were examined using the PA/US system. The PA-sum had high positive correlations with the standard clinical scores of RA (DAS28 [ESR] ρ = 0.754, DAS28 [CRP] ρ = 0.796, SDAI ρ = 0.836, CDAI ρ = 0.837, p < 0.001), which were superior to the PD-sum (DAS28 [ESR] ρ = 0.651, DAS28 [CRP] ρ = 0.676, SDAI ρ = 0.716, CDAI ρ = 0.709, p < 0.001). For the patients with high PA-sum scores, significant differences between hypoxia and hyperoxia were identified in pain visual analog score (p = 0.020) and patient's global assessment (p = 0.026). The PA+SO2 patterns presented moderate and high correlation with PGA (ρ = 0.477, p = 0.0077) and VAS pain score (ρ = 0.717, p < 0.001). CONCLUSION The PA scores have significant correlations with standard clinical scores for RA, and the PA+SO2 patterns are also related with clinical scores that reflect pain severity. PA may have clinical potential in evaluating RA. KEY POINTS • Multimodal photoacoustic/ultrasound imaging is a novel method to assess micro-vessels and oxygenation of local lesions. • Significant correlations between multimodal imaging parameters and clinical scores of RA patients were verified. • The multimodal PA/US system can provide objective imaging parameters, including PA scores of micro-vessels and relative SO2 value, as a supplementary to disease activity evaluation.
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Towards Clinical Translation of LED-Based Photoacoustic Imaging: A Review. SENSORS 2020; 20:s20092484. [PMID: 32349414 PMCID: PMC7249023 DOI: 10.3390/s20092484] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 04/20/2020] [Accepted: 04/22/2020] [Indexed: 12/14/2022]
Abstract
Photoacoustic imaging, with the capability to provide simultaneous structural, functional, and molecular information, is one of the fastest growing biomedical imaging modalities of recent times. As a hybrid modality, it not only provides greater penetration depth than the purely optical imaging techniques, but also provides optical contrast of molecular components in the living tissue. Conventionally, photoacoustic imaging systems utilize bulky and expensive class IV lasers, which is one of the key factors hindering the clinical translation of this promising modality. Use of LEDs which are portable and affordable offers a unique opportunity to accelerate the clinical translation of photoacoustics. In this paper, we first review the development history of LED as an illumination source in biomedical photoacoustic imaging. Key developments in this area, from point-source measurements to development of high-power LED arrays, are briefly discussed. Finally, we thoroughly review multiple phantom, ex-vivo, animal in-vivo, human in-vivo, and clinical pilot studies and demonstrate the unprecedented preclinical and clinical potential of LED-based photoacoustic imaging.
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Dolenec R, Laistler E, Milanic M. Assessing spectral imaging of the human finger for detection of arthritis. BIOMEDICAL OPTICS EXPRESS 2019; 10:6555-6568. [PMID: 31853416 PMCID: PMC6913408 DOI: 10.1364/boe.10.006555] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 11/02/2019] [Accepted: 11/16/2019] [Indexed: 05/11/2023]
Abstract
Rheumatoid arthritis causes changes in the optical properties of tissues in the joints, which could be detected using spectral imaging. This has the potential for development of low cost, non-contact method for early detection of the disease. In this work, hyperspectral imaging system was used to obtain 24 images of proximal interphalangeal joints of 12 healthy volunteers. A large inter-subject variability was observed, but still an increase in transmittance in the spectral range of 600 nm - 950 nm could be associated to the joint in all images. The results of experiments were compared to detailed simulations of light propagation trough tissue. For the simulations, voxelized 3D models of unaffected and inflamed human joints with realistic tissue distributions were constructed from an in-vivo MRI scan of a healthy human finger. The simulated model of healthy finger successfully reproduced the experimental data, while the affected models indicated that the inflammation introduces detectable differences in the spectral and spatial features. The results were used to guide the design of a dedicated imaging system for detection of rheumatoid arthritis, that will be used in an upcoming clinical study.
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Affiliation(s)
- Rok Dolenec
- Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana, Slovenia
- J. Stefan Institute, Ljubljana, Slovenia
| | - Elmar Laistler
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- High Field MR Center, Medical University of Vienna, Vienna, Austria
| | - Matija Milanic
- Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana, Slovenia
- J. Stefan Institute, Ljubljana, Slovenia
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Liu S, Zhang R, Zheng Z, Zheng Y. Electromagnetic⁻Acoustic Sensing for Biomedical Applications. SENSORS (BASEL, SWITZERLAND) 2018; 18:E3203. [PMID: 30248969 PMCID: PMC6210000 DOI: 10.3390/s18103203] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 09/20/2018] [Indexed: 12/29/2022]
Abstract
This paper reviews the theories and applications of electromagnetic⁻acoustic (EMA) techniques (covering light-induced photoacoustic, microwave-induced thermoacoustic, magnetic-modulated thermoacoustic, and X-ray-induced thermoacoustic) belonging to the more general area of electromagnetic (EM) hybrid techniques. The theories cover excitation of high-power EM field (laser, microwave, magnetic field, and X-ray) and subsequent acoustic wave generation. The applications of EMA methods include structural imaging, blood flowmetry, thermometry, dosimetry for radiation therapy, hemoglobin oxygen saturation (SO₂) sensing, fingerprint imaging and sensing, glucose sensing, pH sensing, etc. Several other EM-related acoustic methods, including magnetoacoustic, magnetomotive ultrasound, and magnetomotive photoacoustic are also described. It is believed that EMA has great potential in both pre-clinical research and medical practice.
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Affiliation(s)
- Siyu Liu
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
| | - Ruochong Zhang
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
| | - Zesheng Zheng
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
| | - Yuanjin Zheng
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
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Zhu Y, Xu G, Yuan J, Jo J, Gandikota G, Demirci H, Agano T, Sato N, Shigeta Y, Wang X. Light Emitting Diodes based Photoacoustic Imaging and Potential Clinical Applications. Sci Rep 2018; 8:9885. [PMID: 29959412 PMCID: PMC6026116 DOI: 10.1038/s41598-018-28131-4] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 06/13/2018] [Indexed: 01/25/2023] Open
Abstract
Using low cost and small size light emitting diodes (LED) as the alternative illumination source for photoacoustic (PA) imaging has many advantages, and can largely benefit the clinical translation of the emerging PA imaging technology. Here, we present our development of LED-based PA imaging integrated with B-mode ultrasound. To overcome the challenge of achieving sufficient signal-to-noise ratio by the LED light that is orders of magnitude weaker than lasers, extensive signal averaging over hundreds of pulses is performed. Facilitated by the fast response of the LED and the high-speed driving as well as the high pulse repetition rate up to 16 kHz, B-mode PA images superimposed on gray-scale ultrasound of a biological sample can be achieved in real-time with frame rate up to 500 Hz. The LED-based PA imaging could be a promising tool for several clinical applications, such as assessment of peripheral microvascular function and dynamic changes, diagnosis of inflammatory arthritis, and detection of head and neck cancer.
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Affiliation(s)
- Yunhao Zhu
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, 48109, USA.,Department of Electronic Science and Engineering, Nanjing University, Nanjing, Jiangsu, 21000, China
| | - Guan Xu
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | - Jie Yuan
- Department of Electronic Science and Engineering, Nanjing University, Nanjing, Jiangsu, 21000, China.
| | - Janggun Jo
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | - Girish Gandikota
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | - Hakan Demirci
- Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | | | - Naoto Sato
- PreXion Corporation, Tokyo, 1010041, Japan
| | | | - Xueding Wang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, 48109, USA.
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van den Berg PJ, Daoudi K, Bernelot Moens HJ, Steenbergen W. Feasibility of photoacoustic/ultrasound imaging of synovitis in finger joints using a point-of-care system. PHOTOACOUSTICS 2017; 8:8-14. [PMID: 28913168 PMCID: PMC5587869 DOI: 10.1016/j.pacs.2017.08.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 07/21/2017] [Accepted: 08/28/2017] [Indexed: 05/05/2023]
Abstract
We evaluate a portable ultrasound and photoacoustic imaging (PAI) system for the feasibility of a point-of-care assessment of clinically evident synovitis. Inflamed and non-inflamed proximal interphalangeal joints of 10 patients were examined and compared with joints from 7 healthy volunteers. PAI scans, ultrasound power Doppler (US-PD), and clinical examination were performed. We quantified the amount of photoacoustic (PA) signal using a region of interest (ROI) drawn over the hypertrophic joint space. PAI response was increased 4 to 10 fold when comparing inflamed with contralateral non-inflamed joints and with joints from healthy volunteers (p < 0.001 for both). US-PD and PAI were strongly correlated (Spearman's ρ = 0.64, with 95% CI: 0.42, 0.79). Hence, PAI using a compact handheld probe is capable of detecting clinically evident synovitis. This motivates further investigation into the predictive value of PAI, including multispectral PAI, with other established modalities such as US-PD or MRI.
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Affiliation(s)
- Pim J. van den Berg
- Biomedical Photonic Imaging, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, PO Box 217, 7500 AE, Enschede, The Netherlands
| | - Khalid Daoudi
- Medical Ultrasound Imaging Center, department of Radiology, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Hein J. Bernelot Moens
- Ziekenhuisgroep Twente, Department of Rheumatology, Postbus 546, 7550 AM Hengelo, The Netherlands
| | - Wiendelt Steenbergen
- Biomedical Photonic Imaging, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, PO Box 217, 7500 AE, Enschede, The Netherlands
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Deán-Ben XL, Gottschalk S, Mc Larney B, Shoham S, Razansky D. Advanced optoacoustic methods for multiscale imaging of in vivo dynamics. Chem Soc Rev 2017; 46:2158-2198. [PMID: 28276544 PMCID: PMC5460636 DOI: 10.1039/c6cs00765a] [Citation(s) in RCA: 182] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Visualization of dynamic functional and molecular events in an unperturbed in vivo environment is essential for understanding the complex biology of living organisms and of disease state and progression. To this end, optoacoustic (photoacoustic) sensing and imaging have demonstrated the exclusive capacity to maintain excellent optical contrast and high resolution in deep-tissue observations, far beyond the penetration limits of modern microscopy. Yet, the time domain is paramount for the observation and study of complex biological interactions that may be invisible in single snapshots of living systems. This review focuses on the recent advances in optoacoustic imaging assisted by smart molecular labeling and dynamic contrast enhancement approaches that enable new types of multiscale dynamic observations not attainable with other bio-imaging modalities. A wealth of investigated new research topics and clinical applications is further discussed, including imaging of large-scale brain activity patterns, volumetric visualization of moving organs and contrast agent kinetics, molecular imaging using targeted and genetically expressed labels, as well as three-dimensional handheld diagnostics of human subjects.
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Affiliation(s)
- X L Deán-Ben
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany.
| | - S Gottschalk
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany.
| | - B Mc Larney
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany. and Faculty of Medicine, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany
| | - S Shoham
- Department of Biomedical Engineering, Technion - Israel Institute of Technology, 32000 Haifa, Israel
| | - D Razansky
- Institute for Biological and Medical Imaging (IBMI), Helmholtz Center Munich, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany. and Faculty of Medicine, Technical University of Munich, Ismaninger Str. 22, 81675 Munich, Germany
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11
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Kaiplavil S, Mandelis A, Wang X, Feng T. Photothermal tomography for the functional and structural evaluation, and early mineral loss monitoring in bones. BIOMEDICAL OPTICS EXPRESS 2014; 5:2488-2502. [PMID: 25136480 PMCID: PMC4132983 DOI: 10.1364/boe.5.002488] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 12/15/2013] [Accepted: 01/07/2014] [Indexed: 05/31/2023]
Abstract
Salient features of a new non-ionizing bone diagnostics technique, truncated-correlation photothermal coherence tomography (TC-PCT), exhibiting optical-grade contrast and capable of resolving the trabecular network in three dimensions through the cortical region with and without a soft-tissue overlayer are presented. The absolute nature and early demineralization-detection capability of a marker called thermal wave occupation index, estimated using the proposed modality, have been established. Selective imaging of regions of a specific mineral density range has been demonstrated in a mouse femur. The method is maximum-permissible-exposure compatible. In a matrix of bone and soft-tissue a depth range of ~3.8 mm has been achieved, which can be increased through instrumental and modulation waveform optimization. Furthermore, photoacoustic microscopy, a comparable modality with TC-PCT, has been used to resolve the trabecular structure and for comparison with the photothermal tomography.
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Affiliation(s)
- Sreekumar Kaiplavil
- Center for Advanced Diffusion-Wave Technologies (CADIFT), Dept. of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, ON, M5S 3G8, Canada
| | - Andreas Mandelis
- Center for Advanced Diffusion-Wave Technologies (CADIFT), Dept. of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, ON, M5S 3G8, Canada
| | - Xueding Wang
- Department of Radiology, University of Michigan School of Medicine, Ann Arbor, MI 48109-5667, USA
| | - Ting Feng
- Department of Radiology, University of Michigan School of Medicine, Ann Arbor, MI 48109-5667, USA
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van Es P, Biswas SK, Bernelot Moens HJ, Steenbergen W, Manohar S. Initial results of finger imaging using photoacoustic computed tomography. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:060501. [PMID: 24887742 DOI: 10.1117/1.jbo.19.6.060501] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 05/05/2014] [Indexed: 05/18/2023]
Abstract
We present a photoacoustic computed tomography investigation on a healthy human finger, to image blood vessels with a focus on vascularity across the interphalangeal joints. The cross-sectional images were acquired using an imager specifically developed for this purpose. The images show rich detail of the digital blood vessels with diameters between 100 μm and 1.5 mm in various orientations and at various depths. Different vascular layers in the skin including the subpapillary plexus could also be visualized. Acoustic reflections on the finger bone of photoacoustic signals from skin were visible in sequential slice images along the finger except at the location of the joint gaps. Not unexpectedly, the healthy synovial membrane at the joint gaps was not detected due to its small size and normal vascularization. Future research will concentrate on studying digits afflicted with rheumatoid arthritis to detect the inflamed synovium with its heightened vascularization, whose characteristics are potential markers for disease activity.
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Affiliation(s)
- Peter van Es
- University of Twente, Biomedical Photonic Imaging Group, MIRA Institute, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Samir K Biswas
- University of Twente, Biomedical Photonic Imaging Group, MIRA Institute, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Hein J Bernelot Moens
- Ziekenhuis Groep Twente, Department of Rheumatology, Postbus 546, 7550 AM Hengelo, The Netherlands
| | - Wiendelt Steenbergen
- University of Twente, Biomedical Photonic Imaging Group, MIRA Institute, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Srirang Manohar
- University of Twente, Biomedical Photonic Imaging Group, MIRA Institute, P.O. Box 217, 7500 AE Enschede, The Netherlands
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Gateau J, Caballero MAA, Dima A, Ntziachristos V. Three-dimensional optoacoustic tomography using a conventional ultrasound linear detector array: whole-body tomographic system for small animals. Med Phys 2013; 40:013302. [PMID: 23298121 DOI: 10.1118/1.4770292] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
PURPOSE Optoacoustic imaging relies on the detection of ultrasonic waves induced by laser pulse excitations to map optical absorption in biological tissue. A tomographic geometry employing a conventional ultrasound linear detector array for volumetric optoacoustic imaging is reported. The geometry is based on a translate-rotate scanning motion of the detector array, and capitalizes on the geometrical characteristics of the transducer assembly to provide a large solid angular detection aperture. A system for three-dimensional whole-body optoacoustic tomography of small animals is implemented. METHODS The detection geometry was tested using a 128-element linear array (5.0∕7.0 MHz, Acuson L7, Siemens), moved by steps with a rotation∕translation stage assembly. Translation and rotation range of 13.5 mm and 180°, respectively, were implemented. Optoacoustic emissions were induced in tissue-mimicking phantoms and ex vivo mice using a pulsed laser operating in the near-IR spectral range at 760 nm. Volumetric images were formed using a filtered backprojection algorithm. RESULTS The resolution of the optoacoustic tomography system was measured to be better than 130 μm in-plane and 330 μm in elevation (full width half maximum), and to be homogenous along a 15 mm diameter cross section due to the translate-rotate scanning geometry. Whole-body volumetric optoacoustic images of mice were performed ex vivo, and imaged organs and blood vessels through the intact abdominal and head regions were correlated to the mouse anatomy. CONCLUSIONS Overall, the feasibility of three-dimensional and high-resolution whole-body optoacoustic imaging of small animal using a conventional linear array was demonstrated. Furthermore, the scanning geometry may be used for other linear arrays and is therefore expected to be of great interest for optoacoustic tomography at macroscopic and mesoscopic scale. Specifically, conventional detector arrays with higher central frequencies may be investigated.
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Affiliation(s)
- Jerome Gateau
- Technische Universität München and Helmholtz Zentrum München, Ingoldstädter Landstraße 1, Neuherberg, Germany.
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Xu G, Rajian JR, Girish G, Kaplan MJ, Fowlkes JB, Carson PL, Wang X. Photoacoustic and ultrasound dual-modality imaging of human peripheral joints. JOURNAL OF BIOMEDICAL OPTICS 2013; 18:10502. [PMID: 23235916 PMCID: PMC3520078 DOI: 10.1117/1.jbo.18.1.010502] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 11/20/2012] [Accepted: 11/26/2012] [Indexed: 05/18/2023]
Abstract
A photoacoustic (PA) and ultrasound (US) dual modality system, for imaging human peripheral joints, is introduced. The system utilizes a commercial US unit for both US control imaging and PA signal acquisition. Preliminary in vivo evaluation of the system, on normal volunteers, revealed that this system can recover both the structural and functional information of intra- and extra-articular tissues. Confirmed by the control US images, the system, on the PA mode, can differentiate tendon from surrounding soft tissue based on the endogenous optical contrast. Presenting both morphological and pathological information in joint, this system holds promise for diagnosis and characterization of inflammatory joint diseases such as rheumatoid arthritis.
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Affiliation(s)
- Guan Xu
- University of Michigan Medical School, Department of Radiology, Ann Arbor, Michigan 48109
| | - Justin R. Rajian
- University of Michigan Medical School, Department of Radiology, Ann Arbor, Michigan 48109
| | - Gandikota Girish
- University of Michigan Medical School, Department of Radiology, Ann Arbor, Michigan 48109
| | - Mariana J. Kaplan
- University of Michigan Medical School, Division of Rheumatology, Department of Internal Medicine, Ann Arbor, Michigan 48109
| | - J. Brian Fowlkes
- University of Michigan Medical School, Department of Radiology, Ann Arbor, Michigan 48109
| | - Paul L. Carson
- University of Michigan Medical School, Department of Radiology, Ann Arbor, Michigan 48109
| | - Xueding Wang
- University of Michigan Medical School, Department of Radiology, Ann Arbor, Michigan 48109
- Address all correspondence to: Xueding Wang, University of Michigan Medical School, Department of Radiology, Ann Arbor, Michigan 48109. Tel: 734-647-2728; Fax: 734-764-8541; E-mail:
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Hielscher AH, Kim HK, Montejo LD, Blaschke S, Netz UJ, Zwaka PA, Illing G, Muller GA, Beuthan J. Frequency-domain optical tomographic imaging of arthritic finger joints. IEEE TRANSACTIONS ON MEDICAL IMAGING 2011; 30:1725-36. [PMID: 21964730 DOI: 10.1109/tmi.2011.2135374] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We are presenting data from the largest clinical trial on optical tomographic imaging of finger joints to date. Overall we evaluated 99 fingers of patients affected by rheumatoid arthritis (RA) and 120 fingers from healthy volunteers. Using frequency-domain imaging techniques we show that sensitivities and specificities of 0.85 and higher can be achieved in detecting RA. This is accomplished by deriving multiple optical parameters from the optical tomographic images and combining them for the statistical analysis. Parameters derived from the scattering coefficient perform slightly better than absorption derived parameters. Furthermore we found that data obtained at 600 MHz leads to better classification results than data obtained at 0 or 300 MHz.
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Affiliation(s)
- Andreas H Hielscher
- Department of Biomedical Engineering, Columbia University, New York 10027, USA.
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16
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Matsushita T, Miyati T, Nakayama K, Hamaguchi T, Hayakawa Y, Farman AG, Ohtake S. Qualitative near-infrared vascular imaging system with tuned aperture computed tomography. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:076004. [PMID: 21806265 DOI: 10.1117/1.3595424] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We developed a novel system for imaging and qualitatively analyzing the surface vessels using near-infrared (NIR) radiation using tuned aperture computed tomography (TACT(®)). The system consisted of a NIR-sensitive CCD camera surrounded by sixty light emitting diodes (with wavelengths alternating between 700 or 810 nm). This system produced thin NIR tomograms, under 0.5 mm in slice thickness. The venous oxygenation index reflecting oxygen saturation levels calculated from NIR tomograms was more sensitive than that from the NIR images. This novel system makes it possible to noninvasively obtain NIR tomograms and accurately analyze changes in oxygen saturation.
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Affiliation(s)
- Tatsuhiko Matsushita
- Kanazawa University, Graduate School of Medical Science, Division of Health Science, 5-11-80 Kodatsuno, Kanazawa, 920-0942, Japan.
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17
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Agarwal A, Shao X, Rajian JR, Zhang H, Chamberland DL, Kotov NA, Wang X. Dual-mode imaging with radiolabeled gold nanorods. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:051307. [PMID: 21639567 PMCID: PMC3107834 DOI: 10.1117/1.3580277] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Many nanoparticle contrast agents have difficulties with deep tissue and near-bone imaging due to limited penetration of visible photons in the body and mineralized tissues. We are looking into the possibility of mediating this problem while retaining the capabilities of the high spatial resolution associated with optical imaging. As such, the potential combination of emerging photoacoustic imaging and nuclear imaging in monitoring of antirheumatic drug delivery by using a newly developed dual-modality contrast agent is investigated. The contrast agent is composed of gold nanorods (GNRs) conjugated to the tumor necrosis factor (TNF-α) antibody and is subsequently radiolabeled by (125)I. ELISA experiments designed to test TNF-α binding are performed to prove the specificity and biological activity of the radiolabeled conjugated contrast agent. Photoacoustic and nuclear imaging are performed to visualize the distribution of GNRs in articular tissues of the rat tail joints in situ. Findings from the two imaging modalities correspond well with each other in all experiments. Our system can image GNRs down to a concentration of 10 pM in biological tissues and with a radioactive label of 5 μCi. This study demonstrates the potential of combining photoacoustic and nuclear imaging modalities through one targeted contrast agent for noninvasive monitoring of drug delivery as well as deep and mineralized tissue imaging.
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Affiliation(s)
- Ashish Agarwal
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109-5667, USA
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Dima A, Ntziachristos V. Optoacoustic imaging for clinical applications: devices and methods. ACTA ACUST UNITED AC 2011; 5:263-72. [PMID: 23484501 DOI: 10.1517/17530059.2011.561315] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Optoacoustic (photoacoustic) imaging offers visualization of optical contrast in tissues, within several millimeters to centimeters, with resolutions that are typical of ultrasound imaging. This performance can offer a natural extension to widespread optical microscopy approaches, for applications from small animals to humans. AREAS COVERED An increasing number of optoacoustic approaches are considered for biomedical imaging. Implementations range from handheld and endoscopic operations to fixed scanner set-ups that can address a wide range of preclinical and clinical needs. This article illuminates aspects of the underlying principles of optoacoustic imaging operation and critically reviews the major system trends developed for clinical application. In addition to anatomical imaging, typically performed using single wavelength illumination, multispectral methods are also reviewed as they pertain to functional and molecular imaging. This article also highlights the advantages and limitations as well as the potential of this technology for clinical practice. EXPERT OPINION Optoacoustic imaging is an emerging and highly promising area of the imaging sciences that can offer high-resolution optical visualization deep within tissues. Therefore, it offers a promising alternative to existing optical systems developed for clinical use, which are generally limited to superficial or low-resolution imaging. These up-and-coming features offer a wider variety of optoacoustic approaches that are likely to be clinically deployed in the near future.
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Affiliation(s)
- Alexander Dima
- Institute for Biological and Medical Imaging, Chair for Biological Imaging , Technische Univeristät München & Helmholtz Zentrum München, Munich , Germany
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19
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Abstract
Conventional radiography, ultrasound, CT, MRI, and nuclear imaging are the current imaging modalities used for clinical evaluation of arthritis which is highly prevalent and a leading cause of disability. Some of these types of imaging are also used for monitoring disease progression and treatment response of arthritis. However, their disadvantages limit their utilities, such as ionizing radiation for radiography, CT, and nuclear imaging; suboptimal tissue contrast resolution for radiography, CT, ultrasound, and nuclear imaging; high cost for CT and MRI and nuclear imaging; and long data-acquisition time with ensuing patient discomfort for MRI. Recently, there have been considerable advances in nonionizing noninvasive optical imaging which has demonstrated promise for early diagnosis, monitoring therapeutic interventions and disease progression of arthritis. Optical based molecular imaging modalities such as fluorescence imaging have shown high sensitivity in detection of optical contrast agents and can aid early diagnosis and ongoing evaluation of chronic inflammatory arthritis. Optical transillumination imaging or diffuse optical tomography may differentiate normal joint clear synovial fluid from turbid and pink medium early in the inflammatory process. Fourier transform infrared spectroscopy has been used to evaluate fluid composition from joints affected by arthritis. Hemodynamic changes such as angiogenesis, hypervascularization, and hypoxia in arthritic articular tissue can potentially be observed by diffuse optical tomography and photoacoustic tomography. Optical measurements could also facilitate quantification of hemodynamic properties such as blood volume and oxygenation levels at early stages of inflammatory arthritis. Optical imaging provides methodologies which should contribute to detection of early changes and monitoring of progression in pathological characteristics of arthritis, with relatively simple instrumentation.
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Affiliation(s)
- David Chamberland
- Department of Radiology, University of Michigan School of Medicine, Ann Arbor, 48109, USA
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20
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Darvin ME, Fluhr JW, Caspers P, van der Pool A, Richter H, Patzelt A, Sterry W, Lademann JÃ. In vivodistribution of carotenoids in different anatomical locations of human skin: comparative assessment with two different Raman spectroscopy methods. Exp Dermatol 2009; 18:1060-3. [DOI: 10.1111/j.1600-0625.2009.00946.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Abstract
Photoacoustics has been broadly studied in biomedicine, for both human and small animal tissues. Photoacoustics uniquely combines the absorption contrast of light or radio frequency waves with ultrasound resolution. Moreover, it is non-ionizing and non-invasive, and is the fastest growing new biomedical method, with clinical applications on the way. This review provides a brief recap of recent developments in photoacoustics in biomedicine, from basic principles to applications. The emphasized areas include the new imaging modalities, hybrid detection methods, photoacoustic contrast agents and the photoacoustic Doppler effect, as well as translational research topics.
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Affiliation(s)
- Changhui Li
- Optical Imaging Laboratory, Department of Biomedical Engineering Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Lihong V. Wang
- Optical Imaging Laboratory, Department of Biomedical Engineering Washington University in St. Louis, St. Louis, MO 63130, USA
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22
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Sun Y, Jiang H. Quantitative three-dimensional photoacoustic tomography of the finger joints: phantom studies in a spherical scanning geometry. Phys Med Biol 2009; 54:5457-67. [DOI: 10.1088/0031-9155/54/18/007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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23
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Tang MX, Elson DS, Li R, Dunsby C, Eckersley RJ. Photoacoustics, thermoacoustics, and acousto-optics for biomedical imaging. Proc Inst Mech Eng H 2009; 224:291-306. [DOI: 10.1243/09544119jeim598] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Recently there have been significant advances in developing hybrid techniques combining electromagnetic waves with ultrasound for biomedical imaging, namely photoacoustic, thermoacoustic, and acousto-optic (or ultrasound modulated optical) tomography. All three techniques take advantage of tissue contrast offered by electromagnetic (EM) waves, while achieving good spatial resolution in deeper tissue facilitated by ultrasound. In this review the principles of the three techniques are introduced. A description of existing experimental and image reconstruction techniques is provided. Some recent key developments are highlighted and current issues in each of the areas are discussed.
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Affiliation(s)
- M-X Tang
- Department of Bioengineering, Imperial College London, London, UK
| | - D S Elson
- Institute of Biomedical Engineering, Imperial College London, London, UK
| | - R Li
- Department of Bioengineering, Imperial College London, London, UK
| | - C Dunsby
- Department of Physics, Imperial College London, London, UK
| | - R J Eckersley
- Imaging Sciences Department, Imperial College London, London, UK
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Carson PL, Fenster A. Anniversary paper: evolution of ultrasound physics and the role of medical physicists and the AAPM and its journal in that evolution. Med Phys 2009; 36:411-28. [PMID: 19291980 DOI: 10.1118/1.2992048] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Ultrasound has been the greatest imaging modality worldwide for many years by equipment purchase value and by number of machines and examinations. It is becoming increasingly the front end imaging modality; serving often as an extension of the physician's fingers. We believe that at the other extreme, high-end systems will continue to compete with all other imaging modalities in imaging departments to be the method of choice for various applications, particularly where safety and cost are paramount. Therapeutic ultrasound, in addition to the physiotherapy practiced for many decades, is just coming into its own as a major tool in the long progression to less invasive interventional treatment. The physics of medical ultrasound has evolved over many fronts throughout its history. For this reason, a topical review, rather than a primarily chronological one is presented. A brief review of medical ultrasound imaging and therapy is presented, with an emphasis on the contributions of medical physicists, the American Association of Physicists in Medicine (AAPM) and its publications, particularly its journal Medical Physics. The AAPM and Medical Physics have contributed substantially to training of physicists and engineers, medical practitioners, technologists, and the public.
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Affiliation(s)
- Paul L Carson
- Department of Radiology, University of Michigan Health System, 3218C Medical Science I, B Wing SPC 5667, 1301 Catherine Street, Ann Arbor, Michigan 48109-5667, USA.
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25
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Nikiforidis GC, Sakellaropoulos GC, Kagadis GC. Molecular imaging and the unification of multilevel mechanisms and data in medical physics. Med Phys 2008; 35:3444-52. [DOI: 10.1118/1.2948321] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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Chamberland DL, Agarwal A, Kotov N, Brian Fowlkes J, Carson PL, Wang X. Photoacoustic tomography of joints aided by an Etanercept-conjugated gold nanoparticle contrast agent-an ex vivo preliminary rat study. NANOTECHNOLOGY 2008; 19:095101. [PMID: 21817663 DOI: 10.1088/0957-4484/19/9/095101] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Monitoring of anti-rheumatic drug delivery in experimental models and in human diseases would undoubtedly be very helpful for both basic research and clinical management of inflammatory diseases. In this study, we have investigated the potential of an emerging hybrid imaging technology-photoacoustic tomography-in noninvasive monitoring of anti-TNF drug delivery. After the contrast agent composed of gold nanorods conjugated with Etanercept molecules was produced, ELISA experiments were performed to prove the conjugation and to show that the conjugated anti-TNF-α drug was biologically active. PAT of ex vivo rat tail joints with the joint connective tissue enhanced by intra-articularly injected contrast agent was conducted to examine the performance of PAT in visualizing the distribution of the gold-nanorod-conjugated drug in articular tissues. By using the described system, gold nanorods with a concentration down to 1 pM in phantoms or 10 pM in biological tissues can be imaged with good signal-to-noise ratio and high spatial resolution. This study demonstrates the feasibility of conjugating TNF antagonist pharmaceutical preparations with gold nanorods, preservation of the mechanism of action of TNF antagonist along with preliminary evaluation of novel PAT technology in imaging optical contrast agents conjugated with anti-rheumatic drugs. Further in vivo studies on animals are warranted to test the specific binding between such conjugates and targeted antigen in joint tissues affected by inflammation.
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Chamberland DL, Wang X, Roessler BJ. Photoacoustic tomography of carrageenan-induced arthritis in a rat model. JOURNAL OF BIOMEDICAL OPTICS 2008; 13:011005. [PMID: 18315354 DOI: 10.1117/1.2841028] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Laser-based photoacoustic tomography (PAT), a novel, nonionizing, noninvasive, laser-based technology, has been adapted to the diagnosis and imaging of inflammatory arthritis. A commonly used adjuvant induced arthritis model using carrageenan was employed to simulate acute rheumatoid arthritis in rat tail joints. Cross-sectional photoacoustic images of joints affected by acute inflammation were compared to those of the control. The diameter of the periosteum and the optical absorption of intra-articular tissue were measured on each joint image. Significant differences were found on PAT imaging between the affected joints and the control for both variables measured, including enlarged periosteum diameter and enhanced intra-articular optical absorption occurring in the joints affected with carrageenan-induced arthritis. Anatomical correlation with histological sections of imaged joints and microMRI results verified the findings of PAT. This suggests that PAT has the potential for highly sensitive diagnosis and evaluation of pathologic hallmarks of acute inflammatory arthritis.
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Affiliation(s)
- David L Chamberland
- University of Michigan School of Medicine, Division of Rheumatology, Department of Internal Medicine, Ann Arbor, Michigan 48109, USA
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28
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Ehman RL, Hendee WR, Welch MJ, Dunnick NR, Bresolin LB, Arenson RL, Baum S, Hricak H, Thrall JH. Blueprint for imaging in biomedical research. Radiology 2007; 244:12-27. [PMID: 17507725 DOI: 10.1148/radiol.2441070058] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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29
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Yuan Z, Jiang H. Three-dimensional finite-element-based photoacoustic tomography: reconstruction algorithm and simulations. Med Phys 2007; 34:538-46. [PMID: 17388171 DOI: 10.1118/1.2409234] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
In this paper, a finite element reconstruction algorithm for three-dimensional photoacoustic tomography is described. The algorithm is based on rigorous iterative solution to the Helmholtz photoacoustic wave equation coupled with regularization techniques and is able to recover both the images of absorbed optical energy density and acoustic speed simultaneously. The algorithm is tested using various numerical examples that mimic cancer detection and joint imaging. The results show that the algorithm is able to reconstruct photoacoustic images quantitatively in terms of the location, size, optical and acoustic properties of the target, and background media for various examples examined.
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Affiliation(s)
- Zhen Yuan
- Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611-6131, USA
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