1
|
Mitra M, Haworth A, Gaddale P, Badran F, Lagno N, Pameijer C, Aziz F, Kothapalli SR. Multiwavelength laser diode based portable photoacoustic and ultrasound imaging system for point of care applications. JOURNAL OF BIOPHOTONICS 2024; 17:e202400058. [PMID: 38695390 PMCID: PMC11239316 DOI: 10.1002/jbio.202400058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 04/14/2024] [Accepted: 04/19/2024] [Indexed: 07/13/2024]
Abstract
Vascular diseases are a leading cause of death and disability worldwide. Despite having precursor conditions like peripheral arterial disease (PAD), they are often only diagnosed after the onset of stroke or heart attack. Low-cost, portable, noninvasive, point-of-care (POC), label-free assessment of deep vascular function benefits PAD diagnosis, especially in resource poor settings of the world. Doppler ultrasound-based blood flow measurements can diagnose PAD, albeit with limited sensitivity and specificity. To overcome this, here, we propose the first-of-its-kind dual-modality photoacoustic-and-ultrasound (PAUS) imaging system that integrates a multiwavelength pulsed laser diode (PLD) with a compact ultrasound data acquisition unit. The mesoscopic imaging depth of the portable PLD-PAUS system was validated using tissue phantoms, and its multispectral photoacoustic imaging capabilities were validated using an atherosclerosis-mimicking phantom. Furthermore, we demonstrated high-contrast volumetric in vivo photoacoustic imaging of rodent abdominal vasculature and quantified vessel reactivity due to hypercapnia stimulation. The multiparametric functional and molecular imaging capabilities of the PLD-PAUS system holds promise for POC applications.
Collapse
Affiliation(s)
- Mahaan Mitra
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Abigail Haworth
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Prameth Gaddale
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Faisal Badran
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Nuzhath Lagno
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
| | - Colette Pameijer
- Divison of Vascular Surgery, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Faisal Aziz
- Divison of Vascular Surgery, Department of Surgery, The Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
| | - Sri-Rajasekhar Kothapalli
- Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16802, USA
- Center for Neural Engineering, The Pennsylvania State University, University Park, PA 16802, USA
- Penn State Cancer Institute, The Pennsylvania State University, College of Medicine, Hershey, PA 17033, USA
- Graduate Program in Acoustics, The Pennsylvania State University, University Park, PA 16802, USA
| |
Collapse
|
2
|
Paul A, Mallidi S. U-Net enhanced real-time LED-based photoacoustic imaging. JOURNAL OF BIOPHOTONICS 2024; 17:e202300465. [PMID: 38622811 PMCID: PMC11164633 DOI: 10.1002/jbio.202300465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 02/18/2024] [Accepted: 03/17/2024] [Indexed: 04/17/2024]
Abstract
Photoacoustic (PA) imaging is hybrid imaging modality with good optical contrast and spatial resolution. Portable, cost-effective, smaller footprint light emitting diodes (LEDs) are rapidly becoming important PA optical sources. However, the key challenge faced by the LED-based systems is the low light fluence that is generally compensated by high frame averaging, consequently reducing acquisition frame-rate. In this study, we present a simple deep learning U-Net framework that enhances the signal-to-noise ratio (SNR) and contrast of PA image obtained by averaging low number of frames. The SNR increased by approximately four-fold for both in-class in vitro phantoms (4.39 ± 2.55) and out-of-class in vivo models (4.27 ± 0.87). We also demonstrate the noise invariancy of the network and discuss the downsides (blurry outcome and failure to reduce the salt & pepper noise). Overall, the developed U-Net framework can provide a real-time image enhancement platform for clinically translatable low-cost and low-energy light source-based PA imaging systems.
Collapse
Affiliation(s)
- Avijit Paul
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | | |
Collapse
|
3
|
Na H, Park J, Jeong KH. Plasmon-enhanced optoacoustic transducer with Ecoflex thin film for broadband ultrasound generation using overdriven pulsed laser diode. JOURNAL OF BIOMEDICAL OPTICS 2023; 28:125005. [PMID: 38144698 PMCID: PMC10739335 DOI: 10.1117/1.jbo.28.12.125005] [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: 08/08/2023] [Revised: 12/01/2023] [Accepted: 12/04/2023] [Indexed: 12/26/2023]
Abstract
Significance Ultrasonic transducers facilitate noninvasive biomedical imaging and therapeutic applications. Optoacoustic generation using nanoplasmonic structures provides a technical solution for highly efficient broadband ultrasonic transducer. However, bulky and high-cost nanosecond lasers as conventional excitation sources hinder a compact configuration of transducer. Aim Here, we report a plasmon-enhanced optoacoustic transducer (PEAT) for broadband ultrasound generation, featuring an overdriven pulsed laser diode (LD) and an Ecoflex thin film. The PEAT module consists of an LD, a collimating lens, a focusing lens, and an Ecoflex-coated 3D nanoplasmonic substrate (NPS). Approach The LD is overdriven above its nominal current and precisely modulated to achieve nanosecond pulsed beam with high optical peak power. The focused laser beam is injected on the NPS with high-density electromagnetic hotspots, which allows for the efficient plasmonic photothermal effect. The thermal expansion of Ecoflex finally generates broadband ultrasound. Results The overdriven pulsed LD achieves a maximum optical peak power of 40 W, exceeding the average optical power of 3 W. The 22 μ m thick Ecoflex-coated NPS exhibits an eightfold optoacoustic enhancement with a fractional - 6 dB bandwidth higher than 160% and a peak frequency of 2.5 MHz. In addition, the optoacoustic amplitude is precisely controlled by the optical peak power or the laser pulse width. The PEAT-integrated microfluidic chip clearly demonstrates acoustic atomization by generating aerosol droplets at the air-liquid interface. Conclusions Plasmon-enhanced optoacoustic generation using PEAT can provide an approach for compact and on-demand biomedical applications, such as ultrasound imaging and lab-on-a-chip technologies.
Collapse
Affiliation(s)
- Hamin Na
- Korea Advanced Institute of Science and Technology (KAIST), Department of Bio and Brain Engineering, Daejeon, Republic of Korea
- Korea Advanced Institute of Science and Technology (KAIST), KAIST Institute for Health Science and Technology (KIHST), Daejeon, Republic of Korea
| | - Jaehyeok Park
- Korea Advanced Institute of Science and Technology (KAIST), Department of Bio and Brain Engineering, Daejeon, Republic of Korea
- Korea Advanced Institute of Science and Technology (KAIST), KAIST Institute for Health Science and Technology (KIHST), Daejeon, Republic of Korea
| | - Ki-Hun Jeong
- Korea Advanced Institute of Science and Technology (KAIST), Department of Bio and Brain Engineering, Daejeon, Republic of Korea
- Korea Advanced Institute of Science and Technology (KAIST), KAIST Institute for Health Science and Technology (KIHST), Daejeon, Republic of Korea
| |
Collapse
|
4
|
Paul S, Mulani S, Singh MKA, Singh MS. Improvement of LED-based photoacoustic imaging using lag-coherence factor (LCF) beamforming. Med Phys 2023; 50:7525-7538. [PMID: 37843980 DOI: 10.1002/mp.16780] [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] [Received: 09/12/2022] [Revised: 09/19/2023] [Accepted: 09/20/2023] [Indexed: 10/18/2023] Open
Abstract
BACKGROUND Owing to its portability, affordability, and energy-efficiency, LED-based photoacoustic (PA) imaging is increasingly becoming popular when compared to its laser-based alternative, mainly for superficial vascular imaging applications. However, this technique suffers from low SNR and thereby limited imaging depth. As a result, visual image quality of LED-based PA imaging is not optimal, especially in sub-surface vascular imaging applications. PURPOSE Combination of linear ultrasound (US) probes and LED arrays are the most common implementation in LED-based PA imaging, which is currently being explored for different clinical imaging applications. Traditional delay-and-sum (DAS) is the most common beamforming algorithm in linear array-based PA detection. Side-lobes and reconstruction-related artifacts make the DAS performance unsatisfactory and poor for a clinical-implementation. In this work, we explored a new weighting-based image processing technique for LED-based PAs to yield improved image quality when compared to the traditional methods. METHODS We are proposing a lag-coherence factor (LCF), which is fundamentally based on the combination of the spatial auto-correlation of the detected PA signals. In LCF, the numerator contains lag-delay-multiply-and-sum (DMAS) beamformer instead of a conventional DAS beamformer. A spatial auto-correlation operation is performed between the detected US array signals before using DMAS beamformer. We evaluated the new method on both tissue-mimicking phantom (2D) and human volunteer imaging (3D) data acquired using a commercial LED-based PA imaging system. RESULTS Our novel correlation-based weighting technique showed LED-based PA image quality improvement when it is combined with conventional DAS beamformer. Both phantom and human volunteer imaging results gave a direct confirmation that by introducing LCF, image quality was improved and this method could reduce side-lobes and artifacts when compared to the DAS and coherence-factor (CF) approaches. Signal-to-noise ratio, generalized contrast-to-noise ratio, contrast ratio and spatial resolution were evaluated and compared with conventional beamformers to assess the reconstruction performance in a quantitative way. Results show that our approach offered image quality enhancement with an average signal-to-noise ratio and spatial resolution improvement of around 20% and 25% respectively, when compared with conventional CF based DAS algorithm. CONCLUSIONS Our results demonstrate that the proposed LCF based algorithm performs better than the conventional DAS and CF algorithms by improving signal-to-noise ratio and spatial resolution. Therefore, our new weighting technique could be a promising tool to improve the performance of LED-based PA imaging and thus accelerate its clinical translation.
Collapse
Affiliation(s)
- Souradip Paul
- School of physics, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Sufayan Mulani
- School of physics, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | | | | |
Collapse
|
5
|
Kim M, Pelivanov I, O'Donnell M. Review of Deep Learning Approaches for Interleaved Photoacoustic and Ultrasound (PAUS) Imaging. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2023; 70:1591-1606. [PMID: 37910419 PMCID: PMC10788151 DOI: 10.1109/tuffc.2023.3329119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2023]
Abstract
Photoacoustic (PA) imaging provides optical contrast at relatively large depths within the human body, compared to other optical methods, at ultrasound (US) spatial resolution. By integrating real-time PA and US (PAUS) modalities, PAUS imaging has the potential to become a routine clinical modality bringing the molecular sensitivity of optics to medical US imaging. For applications where the full capabilities of clinical US scanners must be maintained in PAUS, conventional limited view and bandwidth transducers must be used. This approach, however, cannot provide high-quality maps of PA sources, especially vascular structures. Deep learning (DL) using data-driven modeling with minimal human design has been very effective in medical imaging, medical data analysis, and disease diagnosis, and has the potential to overcome many of the technical limitations of current PAUS imaging systems. The primary purpose of this article is to summarize the background and current status of DL applications in PAUS imaging. It also looks beyond current approaches to identify remaining challenges and opportunities for robust translation of PAUS technologies to the clinic.
Collapse
|
6
|
Xu W, Leskinen J, Sahlström T, Happonen E, Tarvainen T, Lehto VP. Assembly of fluorophore J-aggregates with nanospacer onto mesoporous nanoparticles for enhanced photoacoustic imaging. PHOTOACOUSTICS 2023; 33:100552. [PMID: 38021288 PMCID: PMC10658600 DOI: 10.1016/j.pacs.2023.100552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 05/23/2023] [Accepted: 08/26/2023] [Indexed: 12/01/2023]
Abstract
Many fluorophores, such as indocyanine green (ICG), have poor photostability and low photothermal efficiency hindering their wide application in photoacoustic (PA) tomography. In the present study, a supramolecular assembly approach was used to develop the hybrid nanoparticles (Hy NPs) of ICG and porous silicon (PSi) as a novel contrast agent for PA tomography. ICG was assembled on the PSi NPs to form J-aggregates within 30 min. The Hy NPs presented a red-shifted absorption, improved photothermal stability, and enhanced PA performance. Furthermore, 1-dodecene (DOC) was assembled into the NPs as a 'nanospacer', which enhanced non-radiative decay for increased thermal release. Compared to the Hy NPs, adding DOC into the Hy NPs (DOC-Hy) increased the PA signal by 83%. Finally, the DOC-Hy was detectable in PA tomography at 1.5 cm depth in tissue phantom even though its concentration was as low as 6.25 µg/mL, indicating the potential for deep tissue PA imaging.
Collapse
Affiliation(s)
- Wujun Xu
- Department of Technical Physics, University of Eastern Finland, 70210 Kuopio, Finland
| | - Jarkko Leskinen
- Department of Technical Physics, University of Eastern Finland, 70210 Kuopio, Finland
| | - Teemu Sahlström
- Department of Technical Physics, University of Eastern Finland, 70210 Kuopio, Finland
| | - Emilia Happonen
- Department of Technical Physics, University of Eastern Finland, 70210 Kuopio, Finland
| | - Tanja Tarvainen
- Department of Technical Physics, University of Eastern Finland, 70210 Kuopio, Finland
| | - Vesa-Pekka Lehto
- Department of Technical Physics, University of Eastern Finland, 70210 Kuopio, Finland
| |
Collapse
|
7
|
Jhunjhunwala A, Kim J, Kubelick KP, Ethier CR, Emelianov SY. In Vivo Photoacoustic Monitoring of Stem Cell Location and Apoptosis with Caspase-3-Responsive Nanosensors. ACS NANO 2023; 17:17931-17945. [PMID: 37703202 PMCID: PMC10540261 DOI: 10.1021/acsnano.3c04161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 09/06/2023] [Indexed: 09/15/2023]
Abstract
Stem cell therapy has immense potential in a variety of regenerative medicine applications. However, clinical stem cell therapy is severely limited by challenges in assessing the location and functional status of implanted cells in vivo. Thus, there is a great need for longitudinal, noninvasive stem cell monitoring. Here we introduce a multidisciplinary approach combining nanosensor-augmented stem cell labeling with ultrasound guided photoacoustic (US/PA) imaging for the spatial tracking and functional assessment of transplanted stem cell fate. Specifically, our nanosensor incorporates a peptide sequence that is selectively cleaved by caspase-3, the primary effector enzyme in mammalian cell apoptosis; this cleavage event causes labeled cells to show enhanced optical absorption in the first near-infrared (NIR) window. Optimization of labeling protocols and spectral characterization of the nanosensor in vitro showed a 2.4-fold increase in PA signal from labeled cells during apoptosis while simultaneously permitting cell localization. We then successfully tracked the location and apoptotic status of mesenchymal stem cells in a mouse hindlimb ischemia model for 2 weeks in vivo, demonstrating a 4.8-fold increase in PA signal and spectral slope changes in the first NIR window under proapoptotic (ischemic) conditions. We conclude that our nanosensor allows longitudinal, noninvasive, and nonionizing monitoring of stem cell location and apoptosis, which is a significant improvement over current end-point monitoring methods such as biopsies and histological staining of excised tissue.
Collapse
Affiliation(s)
- Anamik Jhunjhunwala
- Wallace
H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Georgia 30332, United States
| | - Jinhwan Kim
- Wallace
H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Georgia 30332, United States
- School
of Electrical & Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Kelsey P. Kubelick
- Wallace
H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Georgia 30332, United States
- School
of Electrical & Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - C. Ross Ethier
- Wallace
H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Georgia 30332, United States
| | - Stanislav Y. Emelianov
- Wallace
H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University School of Medicine, Atlanta, Georgia 30332, United States
- School
of Electrical & Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| |
Collapse
|
8
|
Khan S, Vasudevan S. Biomedical instrumentation of photoacoustic imaging and quantitative sensing for clinical applications. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:091502. [PMID: 37747328 DOI: 10.1063/5.0151882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 09/02/2023] [Indexed: 09/26/2023]
Abstract
Photoacoustic (PA) imaging has been well researched over the last couple of decades and has found many applications in biomedical engineering. This has evinced interest among many scientists in developing this as a compact instrument for biomedical diagnosis. This review discusses various instrumentation developments for PA experimental setups and their applications in the biomedical diagnostic field. It also covers the PA spectral response or PA sensing technique, which uses the spectral information of the PA signal and performs sensing to deliver a fast, cost-effective, and compact screening tool instead of imaging. Primarily, this review provides an overview of PA imaging concepts and the development of hardware instrumentation systems in both the excitation and acquisition stages of this technique. Later, the paper discusses PA sensing, the quantitative spectral parameter extraction from the PA spectrum, and the correlation study of the spectral parameters with the physical parameters of the tissue. This PA sensing technique was used to diagnose various diseases, such as thyroid nodules, breast cancer, renal disorders, and zoonotic diseases, based on the mechanical and biological characteristics of the tissues. The paper culminates with a discussion section that provides future developments that are necessary to take this technique into clinical applications as a quantitative PA imaging technique.
Collapse
Affiliation(s)
- S Khan
- Department of Electrical Engineering, Indian Institute of Technology, Indore 453552, India
| | - S Vasudevan
- Department of Electrical Engineering, Indian Institute of Technology, Indore 453552, India
| |
Collapse
|
9
|
Ren L, Yao T, Nguyen KT, Yuan B. Noninvasive measurement of local temperature using ultrasound-switchable fluorescence. BIOMEDICAL OPTICS EXPRESS 2023; 14:4406-4420. [PMID: 37791288 PMCID: PMC10545191 DOI: 10.1364/boe.497815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 07/26/2023] [Accepted: 07/26/2023] [Indexed: 10/05/2023]
Abstract
Measuring the local background temperature in diseased and inflamed tissues is highly desirable, especially in a non-invasive way. In this work, ultrasound-switchable fluorescence (USF) technique was utilized to estimate the local background temperature for the first time by analyzing the temperature dependence of fluorescence emission from USF contrast agents induced by a focused ultrasound (FU) beam. First, temperature-sensitive USF agents with distinct temperature switching-on thresholds were synthesized, and their thermal switching characteristics were quantified using an independent spectrometer system. Second, the USF contrast agent suspension was injected into a microtube that was embedded into a phantom and the dynamic USF signal was acquired using a camera-based USF system. The differential profile of the measured dynamic USF signal was computed and compared with the thermal switching characteristics. This allowed for the calculation of the local background temperature of the sample in the FU focal volume based on the estimation of heating speed. An infrared (IR) camera was used to acquire the surface temperature of the sample and further compare it with the USF system. The results showed that the difference between the temperatures acquired from the USF thermometry and the IR thermography was 0.64 ± 0.43 °C when operating at the physiological temperature range from 35.27 to 39.31 °C. These results indicated the potential use of the USF system for measuring the local temperature in diseased tissues non-invasively. The designed USF-based thermometry shows a broad application prospect in high spatial resolution temperature imaging with a tunable measurement range in deep tissue.
Collapse
Affiliation(s)
- Liqin Ren
- Ultrasound and Optical Imaging Laboratory, Department of Bioengineering, The University of Texas at Arlington, Arlington, TX 76019, USA
- Joint Biomedical Engineering Program, The University of Texas at Arlington and The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA
| | - Tingfeng Yao
- Ultrasound and Optical Imaging Laboratory, Department of Bioengineering, The University of Texas at Arlington, Arlington, TX 76019, USA
- Joint Biomedical Engineering Program, The University of Texas at Arlington and The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA
| | - Kytai T. Nguyen
- Joint Biomedical Engineering Program, The University of Texas at Arlington and The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA
- Department of Bioengineering, The University of Texas at Arlington, Arlington, TX 76019, USA
| | - Baohong Yuan
- Ultrasound and Optical Imaging Laboratory, Department of Bioengineering, The University of Texas at Arlington, Arlington, TX 76019, USA
- Joint Biomedical Engineering Program, The University of Texas at Arlington and The University of Texas Southwestern Medical Center at Dallas, Dallas, TX 75390, USA
| |
Collapse
|
10
|
Manuel LD, Vincely VD, Bayer CL, McPeak KM. Monodisperse Sub-100 nm Au Nanoshells for Low-Fluence Deep-Tissue Photoacoustic Imaging. NANO LETTERS 2023; 23:7334-7340. [PMID: 37540682 PMCID: PMC10450810 DOI: 10.1021/acs.nanolett.3c01696] [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: 05/08/2023] [Revised: 07/29/2023] [Indexed: 08/06/2023]
Abstract
Nanoparticles with high absorption cross sections will advance therapeutic and bioimaging nanomedicine technologies. While Au nanoshells have shown great promise in nanomedicine, state-of-the-art synthesis methods result in scattering-dominant particles, mitigating their efficacy in absorption-based techniques that leverage the photothermal effect, such as photoacoustic (PA) imaging. We introduce a highly reproducible synthesis route to monodisperse sub-100 nm Au nanoshells with an absorption-dominant optical response. Au nanoshells with 48 nm SiO2 cores and 7 nm Au shells show a 14-fold increase in their volumetric absorption coefficient compared to commercial Au nanoshells with dimensions commonly used in nanomedicine. PA imaging with Au nanoshell contrast agents showed a 50% improvement in imaging depth for sub-100 nm Au nanoshells compared with the smallest commercially available nanoshells in a turbid phantom. Furthermore, the high PA signal at low fluences, enabled by sub-100 nm nanoshells, will aid the deployment of low-cost, low-fluence light-emitting diodes for PA imaging.
Collapse
Affiliation(s)
- Luis D.
B. Manuel
- Gordon
and Mary Cain Department of Chemical Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Vinoin Devpaul Vincely
- Department
of Biomedical Engineering, Tulane University, New Orleans, Louisiana 70118, United States
| | - Carolyn L. Bayer
- Department
of Biomedical Engineering, Tulane University, New Orleans, Louisiana 70118, United States
| | - Kevin M. McPeak
- Gordon
and Mary Cain Department of Chemical Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| |
Collapse
|
11
|
Jin H, Zheng Z, Cui Z, Jiang Y, Chen G, Li W, Wang Z, Wang J, Yang C, Song W, Chen X, Zheng Y. A flexible optoacoustic blood 'stethoscope' for noninvasive multiparametric cardiovascular monitoring. Nat Commun 2023; 14:4692. [PMID: 37542045 PMCID: PMC10403590 DOI: 10.1038/s41467-023-40181-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Accepted: 07/13/2023] [Indexed: 08/06/2023] Open
Abstract
Quantitative and multiparametric blood analysis is of great clinical importance in cardiovascular disease diagnosis. Although there are various methods to extract blood information, they often require invasive procedures, lack continuity, involve bulky instruments, or have complicated testing procedures. Flexible sensors can realize on-skin assessment of several vital signals, but generally exhibit limited function to monitor blood characteristics. Here, we report a flexible optoacoustic blood 'stethoscope' for noninvasive, multiparametric, and continuous cardiovascular monitoring, without requiring complicated procedures. The optoacoustic blood 'stethoscope' features the light delivery elements to illuminate blood and the piezoelectric acoustic elements to capture light-induced acoustic waves. We show that the optoacoustic blood 'stethoscope' can adhere to the skin for continuous and non-invasive in-situ monitoring of multiple cardiovascular biomarkers, including hypoxia, intravascular exogenous agent concentration decay, and hemodynamics, which can be further visualized with a tailored 3D algorithm. Demonstrations on both in-vivo animal trials and human subjects highlight the optoacoustic blood 'stethoscope''s potential for cardiovascular disease diagnosis and prediction.
Collapse
Affiliation(s)
- Haoran Jin
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- The State Key Laboratory of Fluid Power and Mechatronic Systems, School of Mechanical Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Zesheng Zheng
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- Institute of Microelectronics, Agency for Science, Technology and Research, Singapore, 138634, Singapore
| | - Zequn Cui
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Ying Jiang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Geng Chen
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Wenlong Li
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Zhimin Wang
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore
| | - Jilei Wang
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Chuanshi Yang
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Weitao Song
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Xiaodong Chen
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.
| | - Yuanjin Zheng
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, 639798, Singapore.
| |
Collapse
|
12
|
John S, Hester S, Basij M, Paul A, Xavierselvan M, Mehrmohammadi M, Mallidi S. Niche preclinical and clinical applications of photoacoustic imaging with endogenous contrast. PHOTOACOUSTICS 2023; 32:100533. [PMID: 37636547 PMCID: PMC10448345 DOI: 10.1016/j.pacs.2023.100533] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 06/30/2023] [Accepted: 07/14/2023] [Indexed: 08/29/2023]
Abstract
In the past decade, photoacoustic (PA) imaging has attracted a great deal of popularity as an emergent diagnostic technology owing to its successful demonstration in both preclinical and clinical arenas by various academic and industrial research groups. Such steady growth of PA imaging can mainly be attributed to its salient features, including being non-ionizing, cost-effective, easily deployable, and having sufficient axial, lateral, and temporal resolutions for resolving various tissue characteristics and assessing the therapeutic efficacy. In addition, PA imaging can easily be integrated with the ultrasound imaging systems, the combination of which confers the ability to co-register and cross-reference various features in the structural, functional, and molecular imaging regimes. PA imaging relies on either an endogenous source of contrast (e.g., hemoglobin) or those of an exogenous nature such as nano-sized tunable optical absorbers or dyes that may boost imaging contrast beyond that provided by the endogenous sources. In this review, we discuss the applications of PA imaging with endogenous contrast as they pertain to clinically relevant niches, including tissue characterization, cancer diagnostics/therapies (termed as theranostics), cardiovascular applications, and surgical applications. We believe that PA imaging's role as a facile indicator of several disease-relevant states will continue to expand and evolve as it is adopted by an increasing number of research laboratories and clinics worldwide.
Collapse
Affiliation(s)
- Samuel John
- Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA
| | - Scott Hester
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | - Maryam Basij
- Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA
| | - Avijit Paul
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | | | - Mohammad Mehrmohammadi
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester, NY, USA
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
- Wilmot Cancer Institute, Rochester, NY, USA
| | - Srivalleesha Mallidi
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA
| |
Collapse
|
13
|
Lin R, Zhang J, Gao W, Wang X, Lv S, Lam KH, Gong X. A Miniature Multi-Functional Photoacoustic Probe. MICROMACHINES 2023; 14:1269. [PMID: 37374854 DOI: 10.3390/mi14061269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 06/08/2023] [Accepted: 06/15/2023] [Indexed: 06/29/2023]
Abstract
Photoacoustic technology is a promising tool to provide morphological and functional information in biomedical research. To enhance the imaging efficiency, the reported photoacoustic probes have been designed coaxially involving complicated optical/acoustic prisms to bypass the opaque piezoelectric layer of ultrasound transducers, but this has led to bulky probes and has hindered the applications in limited space. Though the emergence of transparent piezoelectric materials helps to save effort on the coaxial design, the reported transparent ultrasound transducers were still bulky. In this work, a miniature photoacoustic probe with an outer diameter of 4 mm was developed, in which an acoustic stack was made with a combination of transparent piezoelectric material and a gradient-index lens as a backing layer. The transparent ultrasound transducer exhibited a high center frequency of ~47 MHz and a -6 dB bandwidth of 29.4%, which could be easily assembled with a pigtailed ferrule of a single-mode fiber. The multi-functional capability of the probe was successfully validated through experiments of fluid flow sensing and photoacoustic imaging.
Collapse
Affiliation(s)
- Riqiang Lin
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
- Research Center for Biomedical Optics and Molecular Imaging, Shenzhen Key Laboratory for Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Optical Imaging Technology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Jiaming Zhang
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Wen Gao
- Research Center for Biomedical Optics and Molecular Imaging, Shenzhen Key Laboratory for Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Optical Imaging Technology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Xiatian Wang
- Research Center for Biomedical Optics and Molecular Imaging, Shenzhen Key Laboratory for Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Optical Imaging Technology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Shengmiao Lv
- Research Center for Biomedical Optics and Molecular Imaging, Shenzhen Key Laboratory for Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Optical Imaging Technology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| | - Kwok-Ho Lam
- Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
- Centre for Medical and Industrial Ultrasonics, James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK
| | - Xiaojing Gong
- Research Center for Biomedical Optics and Molecular Imaging, Shenzhen Key Laboratory for Molecular Imaging, Guangdong Provincial Key Laboratory of Biomedical Optical Imaging Technology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
| |
Collapse
|
14
|
Liu X, Kalva SK, Lafci B, Nozdriukhin D, Deán-Ben XL, Razansky D. Full-view LED-based optoacoustic tomography. PHOTOACOUSTICS 2023; 31:100521. [PMID: 37342502 PMCID: PMC10277581 DOI: 10.1016/j.pacs.2023.100521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 05/30/2023] [Accepted: 06/06/2023] [Indexed: 06/23/2023]
Abstract
Optoacoustic tomography is commonly performed with bulky and expensive short-pulsed solid-state lasers providing high per-pulse energies in the millijoule range. Light emitting diodes (LEDs) represent a cost-effective and portable alternative for optoacoustic signal excitation that can additionally provide excellent pulse-to-pulse stability. Herein, we introduce a full-view LED-based optoacoustic tomography (FLOAT) system for deep tissue in vivo imaging. It is based on a custom-made electronic unit driving a stacked array of LEDs, which attains 100 ns pulse width and highly stable (0.62 % standard deviation) total per-pulse energy of 0.48 mJ. The illumination source is integrated into a circular array of cylindrically-focused ultrasound detection elements to result in a full-view tomographic configuration, which plays a critical role in circumventing limited-view effects, enhancing the effective field-of-view and image quality for cross-sectional (2D) imaging. We characterized the FLOAT performance in terms of pulse width, power stability, excitation light distribution, signal-to-noise and penetration depth. FLOAT of the human finger revealed a comparable imaging performance to that achieved with the standard pulsed Nd:YAG laser. It is anticipated that this compact, affordable and versatile illumination technology will facilitate optoacoustic imaging developments in resource-limited settings for biological and clinical applications.
Collapse
Affiliation(s)
- Xiang Liu
- Institute of Pharmacology and Toxicology and Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Zurich CH-8057, Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich CH-8093, Switzerland
| | - Sandeep Kumar Kalva
- Institute of Pharmacology and Toxicology and Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Zurich CH-8057, Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich CH-8093, Switzerland
| | - Berkan Lafci
- Institute of Pharmacology and Toxicology and Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Zurich CH-8057, Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich CH-8093, Switzerland
| | - Daniil Nozdriukhin
- Institute of Pharmacology and Toxicology and Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Zurich CH-8057, Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich CH-8093, Switzerland
| | - Xosé Luís Deán-Ben
- Institute of Pharmacology and Toxicology and Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Zurich CH-8057, Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich CH-8093, Switzerland
| | - Daniel Razansky
- Institute of Pharmacology and Toxicology and Institute for Biomedical Engineering, Faculty of Medicine, University of Zurich, Zurich CH-8057, Switzerland
- Institute for Biomedical Engineering, Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich CH-8093, Switzerland
| |
Collapse
|
15
|
Jo J, Mills D, Dentinger A, Chamberland D, Abdulaziz NM, Wang X, Schiopu E, Gandikota G. Photoacoustic Imaging of COVID-19 Vaccine Site Inflammation of Autoimmune Disease Patients. SENSORS (BASEL, SWITZERLAND) 2023; 23:2789. [PMID: 36904999 PMCID: PMC10006996 DOI: 10.3390/s23052789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 02/25/2023] [Accepted: 03/01/2023] [Indexed: 06/18/2023]
Abstract
Based on the observations made in rheumatology clinics, autoimmune disease (AD) patients on immunosuppressive (IS) medications have variable vaccine site inflammation responses, whose study may help predict the long-term efficacy of the vaccine in this at-risk population. However, the quantitative assessment of the inflammation of the vaccine site is technically challenging. In this study analyzing AD patients on IS medications and normal control subjects, we imaged the inflammation of the vaccine site 24 h after mRNA COVID-19 vaccinations were administered using both the emerging photoacoustic imaging (PAI) method and the established Doppler ultrasound (US) method. A total of 15 subjects were involved, including 6 AD patients on IS and 9 normal control subjects, and the results from the two groups were compared. Compared to the results obtained from the control subjects, the AD patients on IS medications showed statistically significant reductions in vaccine site inflammation, indicating that immunosuppressed AD patients also experience local inflammation after mRNA vaccination but not in as clinically apparent of a manner when compared to non-immunosuppressed non-AD individuals. Both PAI and Doppler US were able to detect mRNA COVID-19 vaccine-induced local inflammation. PAI, based on the optical absorption contrast, shows better sensitivity in assessing and quantifying the spatially distributed inflammation in soft tissues at the vaccine site.
Collapse
Affiliation(s)
- Janggun Jo
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - David Mills
- General Electric Research, Niskayuna, NY 12309, USA
| | | | - David Chamberland
- Department of Internal Medicine, Division of Rheumatology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nada M. Abdulaziz
- Department of Internal Medicine, Division of Rheumatology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Xueding Wang
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Elena Schiopu
- Division of Rheumatology, Medical College of Georgia at Augusta University, Augusta, GA 30912, USA
| | - Girish Gandikota
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| |
Collapse
|
16
|
Zan C, An J, Wu Z, Li S. Engineering molecular nanoprobes to target early atherosclerosis: Precise diagnostic tools and promising therapeutic carriers. Nanotheranostics 2023; 7:327-344. [PMID: 37064609 PMCID: PMC10093416 DOI: 10.7150/ntno.82654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 03/02/2023] [Indexed: 04/18/2023] Open
Abstract
Atherosclerosis, an inflammation-driven chronic blood vessel disease, is a major contributor to devastating cardiovascular events, bringing serious social and economic burdens. Currently, non-invasive diagnostic and therapeutic techniques in combination with novel nanosized materials as well as established molecular targets are under active investigation to develop integrated molecular imaging approaches, precisely visualizing and/or even effectively reversing early-stage plaques. Besides, mechanistic investigation in the past decades provides many potent candidates extensively involved in the initiation and progression of atherosclerosis. Recent hotly-studied imaging nanoprobes for detecting early plaques mainly including optical nanoprobes, photoacoustic nanoprobes, magnetic resonance nanoprobes, positron emission tomography nanoprobes, and other dual- and multi-modality imaging nanoprobes, have been proven to be surface functionalized with important molecular targets, which occupy tailored physical and biological properties for atherogenesis. Of note, these engineering nanoprobes provide long blood-pool residence and specific molecular targeting, which allows efficient recognition of early-stage atherosclerotic plaques and thereby function as a novel type of precise diagnostic tools as well as potential therapeutic carriers of anti-atherosclerosis drugs. There have been no available nanoprobes applied in the clinics so far, although many newly emerged nanoprobes, as exemplified by aggregation-induced emission nanoprobes and TiO2 nanoprobes, have been tested for cell lines in vitro and atherogenic animal models in vivo, achieving good experimental effects. Therefore, there is an urgent call to translate these preclinical results for nanoprobes into clinical trials. For this reason, this review aims to give an overview of currently investigated nanoprobes in the context of atherosclerosis, summarize relevant published studies showing applications of different kinds of formulated nanoprobes in early detection and reverse of plaques, discuss recent advances and some limitations thereof, and provide some insights into the development of the new generation of more precise and efficient molecular nanoprobes, with a critical property of specifically targeting early atherosclerosis.
Collapse
Affiliation(s)
- Chunfang Zan
- Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Taiyuan, China
- Collaborative Innovation Center for Molecular Imaging of Precision Medicine, Shanxi Medical University, Taiyuan, China
| | - Jie An
- Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Taiyuan, China
- Collaborative Innovation Center for Molecular Imaging of Precision Medicine, Shanxi Medical University, Taiyuan, China
| | - Zhifang Wu
- Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Taiyuan, China
- Collaborative Innovation Center for Molecular Imaging of Precision Medicine, Shanxi Medical University, Taiyuan, China
- ✉ Corresponding authors: Prof. Zhifang Wu, E-mail: . Prof. Sijin Li, E-mail:
| | - Sijin Li
- Department of Nuclear Medicine, First Hospital of Shanxi Medical University, Taiyuan, China
- Collaborative Innovation Center for Molecular Imaging of Precision Medicine, Shanxi Medical University, Taiyuan, China
- ✉ Corresponding authors: Prof. Zhifang Wu, E-mail: . Prof. Sijin Li, E-mail:
| |
Collapse
|
17
|
Tsunoi Y, Sato N, Nishidate I, Ichihashi F, Saitoh D, Sato S. Burn depth assessment by dual-wavelength light emitting diodes-excited photoacoustic imaging in rats. Wound Repair Regen 2023; 31:69-76. [PMID: 36177703 DOI: 10.1111/wrr.13056] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 08/14/2022] [Accepted: 09/11/2022] [Indexed: 02/01/2023]
Abstract
Accurate burn depth assessment is crucial to determine treatment plans for burn patients. We have previously proposed a method for performing burn depth assessments based on photoacoustic (PA) imaging, and we have demonstrated the validity of this method, which allows the successful detection of PA signals originating from the blood under the bloodless burned tissue, using rat burn models. Based on these findings, we started a clinical study in which we faced two technical issues: (1) When the burn depth was shallow, PA signals due to skin contamination and/or melanin in the epidermis (surface signals) could not be distinguished from PA signals originating from the blood in the dermis; (2) the size of the system was too large. To solve these issues, we propose a burn depth diagnosis based on dual-wavelength light emitting diodes (LEDs)-excited PA imaging. The use of LEDs rendered the system compact compared to the previous one that used a conventional solid-state laser. We replicated human burned skin by applying a titrated synthetic melanin solution onto the wound surface in albino rat burn models and measured their burn depths by PA excitation at 690 and 850 nm, where melanin and haemoglobin show greatly different absorption coefficients. As a result, the surface signals were eliminated by subtracting the PA signals at 690 nm from those at 850 nm. The resultant estimated burn depths were strongly correlated with the histological assessment results. The validity of the proposed method was also examined using a burn model of rats with real melanin.
Collapse
Affiliation(s)
- Yasuyuki Tsunoi
- Division of Bioinformation and Therapeutic Systems, National Defense Medical College Research Institute, Tokorozawa, Saitama, Japan
| | - Naoto Sato
- Research and Development Department, Cyberdyne, Inc, Tsukuba, Ibaraki, Japan
| | - Izumi Nishidate
- Graduate School of Bio-application and Systems Engineering, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan
| | - Fumiyuki Ichihashi
- Research and Development Department, Cyberdyne, Inc, Tsukuba, Ibaraki, Japan
| | - Daizoh Saitoh
- Division of Basic Traumatology, National Defense Medical College Research Institute, Tokorozawa, Saitama, Japan
| | - Shunichi Sato
- Division of Bioinformation and Therapeutic Systems, National Defense Medical College Research Institute, Tokorozawa, Saitama, Japan
| |
Collapse
|
18
|
A photoacoustic patch for three-dimensional imaging of hemoglobin and core temperature. Nat Commun 2022; 13:7757. [PMID: 36522334 PMCID: PMC9755152 DOI: 10.1038/s41467-022-35455-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 12/01/2022] [Indexed: 12/23/2022] Open
Abstract
Electronic patches, based on various mechanisms, allow continuous and noninvasive monitoring of biomolecules on the skin surface. However, to date, such devices are unable to sense biomolecules in deep tissues, which have a stronger and faster correlation with the human physiological status than those on the skin surface. Here, we demonstrate a photoacoustic patch for three-dimensional (3D) mapping of hemoglobin in deep tissues. This photoacoustic patch integrates an array of ultrasonic transducers and vertical-cavity surface-emitting laser (VCSEL) diodes on a common soft substrate. The high-power VCSEL diodes can generate laser pulses that penetrate >2 cm into biological tissues and activate hemoglobin molecules to generate acoustic waves, which can be collected by the transducers for 3D imaging of the hemoglobin with a high spatial resolution. Additionally, the photoacoustic signal amplitude and temperature have a linear relationship, which allows 3D mapping of core temperatures with high accuracy and fast response. With access to biomolecules in deep tissues, this technology adds unprecedented capabilities to wearable electronics and thus holds significant implications for various applications in both basic research and clinical practice.
Collapse
|
19
|
Fu L, Khazaeinezhad R, Hariri A, Qi B, Chen C, Jokerst JV. Posterior photoacoustic/ultrasound imaging of the periodontal pocket with a compact intraoral transducer. PHOTOACOUSTICS 2022; 28:100408. [PMID: 36204181 PMCID: PMC9530592 DOI: 10.1016/j.pacs.2022.100408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 08/15/2022] [Accepted: 09/25/2022] [Indexed: 06/16/2023]
Abstract
Periodontitis is a public issue and imaging periodontal pocket is important to evaluate periodontitis. Regular linear transducers have limitations in imaging the posterior teeth due to their geometry restrictions. Here we characterized a transducer that can image the posterior teeth including assessment of periodontal pockets via a combination of photoacoustic and ultrasound imaging. Unlike conventional transducer design, this device has a toothbrush-shaped form factor with a side-view transducer to image molars (total size: 1 ×1.9 cm). A laser diode was integrated as the light source to reduce the cost and size and facilitates clinical transition. The in vivo imaging of a molar of a periodontal patient demonstrated that the transducer could image in the posterior area of gum in vivo; the value determined by imaging was within 7 % of the value measured clinically.
Collapse
Affiliation(s)
- Lei Fu
- Department of NanoEngineering, University of California San Diego, La Jolla, CA 92093, USA
| | | | - Ali Hariri
- StyloSonic LLC, Lake Forest, CA 92630, USA
| | - Baiyan Qi
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA 92093, USA
| | - Casey Chen
- Herman Ostrow School of Dentistry, University of Southern California, 925 West 34th Street, Los Angeles, CA 90089, USA
| | - Jesse V. Jokerst
- Department of NanoEngineering, University of California San Diego, La Jolla, CA 92093, USA
- StyloSonic LLC, Lake Forest, CA 92630, USA
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA 92093, USA
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA
| |
Collapse
|
20
|
Fang Z, Gao F, Jin H, Liu S, Wang W, Zhang R, Zheng Z, Xiao X, Tang K, Lou L, Tang KT, Chen J, Zheng Y. A Review of Emerging Electromagnetic-Acoustic Sensing Techniques for Healthcare Monitoring. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2022; 16:1075-1094. [PMID: 36459601 DOI: 10.1109/tbcas.2022.3226290] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Conventional electromagnetic (EM) sensing techniques such as radar and LiDAR are widely used for remote sensing, vehicle applications, weather monitoring, and clinical monitoring. Acoustic techniques such as sonar and ultrasound sensors are also used for consumer applications, such as ranging and in vivo medical/healthcare applications. It has been of long-term interest to doctors and clinical practitioners to realize continuous healthcare monitoring in hospitals and/or homes. Physiological and biopotential signals in real-time serve as important health indicators to predict and prevent serious illness. Emerging electromagnetic-acoustic (EMA) sensing techniques synergistically combine the merits of EM sensing with acoustic imaging to achieve comprehensive detection of physiological and biopotential signals. Further, EMA enables complementary fusion sensing for challenging healthcare settings, such as real-world long-term monitoring of treatment effects at home or in remote environments. This article reviews various examples of EMA sensing instruments, including implementation, performance, and application from the perspectives of circuits to systems. The novel and significant applications to healthcare are discussed. Three types of EMA sensors are presented: (1) Chip-based radar sensors for health status monitoring, (2) Thermo-acoustic sensing instruments for biomedical applications, and (3) Photoacoustic (PA) sensing and imaging systems, including dedicated reconstruction algorithms were reviewed from time-domain, frequency-domain, time-reversal, and model-based solutions. The future of EMA techniques for continuous healthcare with enhanced accuracy supported by artificial intelligence (AI) is also presented.
Collapse
|
21
|
Mantri Y, Mishra A, Anderson CA, Jokerst JV. Photoacoustic imaging to monitor outcomes during hyperbaric oxygen therapy: validation in a small cohort and case study in a bilateral chronic ischemic wound. BIOMEDICAL OPTICS EXPRESS 2022; 13:5683-5694. [PMID: 36733747 PMCID: PMC9872873 DOI: 10.1364/boe.472568] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 09/19/2022] [Accepted: 09/19/2022] [Indexed: 06/18/2023]
Abstract
Hyperbaric oxygen therapy (HBO2) is a common therapeutic modality that drives oxygen into hypoxic tissue to promote healing. Here, ten patients undergoing HBO2 underwent PA oximetry of the left radial artery and forearm pre- and post-HBO2; this cohort validated the use of PA imaging in HBO2. There was a significant increase in radial artery oxygenation after HBO2 (p = 0.002) in the validation cohort. We also include a case study: a non-diabetic male in his 50s (HB 010) presenting with bilateral ischemic and gangrenous wounds. HB 010 showed higher perfusion and oxygen saturation on the right foot than the left after HBO2 which correlated with independent surgical observations. Imaging assisted with limb salvage treatment. Hence, this work shows that PA imaging can measure changes in arterial oxygen saturation due to HBO2; it can also produce 3D maps of tissue oxygenation and evaluate response to therapy during HBO2.
Collapse
Affiliation(s)
- Yash Mantri
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Aditya Mishra
- Materials Science Program, University of California San Diego, La Jolla, CA, USA
| | - Caesar A. Anderson
- Department of Emergency Medicine, Hyperbaric and Wound Healing Center, University of California San Diego, Encinitas, CA, USA
| | - Jesse V. Jokerst
- Materials Science Program, University of California San Diego, La Jolla, CA, USA
- Department of Nanoengineering, University of California San Diego, La Jolla, CA, USA
- Department of Radiology, University of California San Diego, La Jolla, CA, USA
| |
Collapse
|
22
|
Wang Y, Tsai CH, Chu TS, Hung YT, Lee MY, Chen HH, Chen LT, Ger TR, Wang YH, Chiang NJ, Liao LD. Revisiting the cerebral hemodynamics of awake, freely moving rats with repeated ketamine self-administration using a miniature photoacoustic imaging system. NEUROPHOTONICS 2022; 9:045003. [PMID: 36338453 PMCID: PMC9623815 DOI: 10.1117/1.nph.9.4.045003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
SIGNIFICANCE Revealing the dynamic associations between brain functions and behaviors is a significant challenge in neurotechnology, especially for awake subjects. Imaging cerebral hemodynamics in awake animal models is important because the collected data more realistically reflect human disease states. AIM We previously reported a miniature head-mounted scanning photoacoustic imaging (hmPAI) system. In the present study, we utilized this system to investigate the effects of ketamine on the cerebral hemodynamics of normal rats and rats subjected to prolonged ketamine self-administration. APPROACH The cortical superior sagittal sinus (SSS) was continuously monitored. The full-width at half-maximum (FWHM) of the photoacoustic (PA) A-line signal was used as an indicator of the SSS diameter, and the number of pixels in PA B-scan images was used to investigate changes in the cerebral blood volume (CBV). RESULTS We observed a significantly higher FWHM (blood vessel diameter) and CBV in normal rats injected with ketamine than in normal rats injected with saline. For rats subjected to prolonged ketamine self-administration, no significant changes in either the blood vessel diameter or CBV were observed. CONCLUSIONS The lack of significant change in prolonged ketamine-exposed rats was potentially due to an increased ketamine tolerance. Our device can reliably detect changes in the dilation of cortical blood vessels and the CBV. This study validates the utility of the developed hmPAI system in an awake, freely moving rat model for behavioral, cognitive, and preclinical cerebral disease studies.
Collapse
Affiliation(s)
- Yuhling Wang
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
| | - Chia-Hua Tsai
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
| | - Tsung-Sheng Chu
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
- Chung Yuan Christian University, Department of Biomedical Engineering, Taoyuan City, Taiwan
| | - Yun-Ting Hung
- National Health Research Institutes, Center for Neuropsychiatric Research, Zhunan Town, Miaoli County, Taiwan
| | - Mei-Yi Lee
- National Health Research Institutes, Center for Neuropsychiatric Research, Zhunan Town, Miaoli County, Taiwan
| | - Hwei-Hsien Chen
- National Health Research Institutes, Center for Neuropsychiatric Research, Zhunan Town, Miaoli County, Taiwan
| | - Li-Tzong Chen
- Kaohsiung Medical University, Kaohsiung Medical University Hospital, Kaohsiung City, Taiwan
- National Health Research Institutes, National Institute of Cancer Research, Zhunan Town, Miaoli County, Taiwan
| | - Tzong-Rong Ger
- Chung Yuan Christian University, Department of Biomedical Engineering, Taoyuan City, Taiwan
| | - Yung-Hsuan Wang
- National Health Research Institutes, National Institute of Cancer Research, Zhunan Town, Miaoli County, Taiwan
| | - Nai-Jung Chiang
- National Health Research Institutes, National Institute of Cancer Research, Zhunan Town, Miaoli County, Taiwan
- Taipei Veterans General Hospital, Department of Oncology, Taipei City, Taiwan
| | - Lun-De Liao
- National Health Research Institutes, Institute of Biomedical Engineering and Nanomedicine, Zhunan Town, Miaoli County, Taiwan
| |
Collapse
|
23
|
Wu L, Zeng W, Ishigaki Y, Zhang J, Bai H, Harimoto T, Suzuki T, Ye D. A Ratiometric Photoacoustic Probe with a Reversible Response to Hydrogen Sulfide and Hydroxyl Radicals for Dynamic Imaging of Liver Inflammation. Angew Chem Int Ed Engl 2022; 61:e202209248. [DOI: 10.1002/anie.202209248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Indexed: 11/09/2022]
Affiliation(s)
- Luyan Wu
- State Key Laboratory of Analytical Chemistry for Life Science Chemistry and Biomedicine Innovation Center (ChemBIC) School of Chemistry and Chemical Engineering Nanjing University Nanjing 210023 China
| | - Wenhui Zeng
- State Key Laboratory of Analytical Chemistry for Life Science Chemistry and Biomedicine Innovation Center (ChemBIC) School of Chemistry and Chemical Engineering Nanjing University Nanjing 210023 China
| | - Yusuke Ishigaki
- Department of Chemistry Faculty of Science Hokkaido University N10 W8, North-ward Sapporo 060-0810 Japan
| | - Junya Zhang
- State Key Laboratory of Analytical Chemistry for Life Science Chemistry and Biomedicine Innovation Center (ChemBIC) School of Chemistry and Chemical Engineering Nanjing University Nanjing 210023 China
| | - He Bai
- State Key Laboratory of Analytical Chemistry for Life Science Chemistry and Biomedicine Innovation Center (ChemBIC) School of Chemistry and Chemical Engineering Nanjing University Nanjing 210023 China
| | - Takashi Harimoto
- Department of Chemistry Faculty of Science Hokkaido University N10 W8, North-ward Sapporo 060-0810 Japan
| | - Takanori Suzuki
- Department of Chemistry Faculty of Science Hokkaido University N10 W8, North-ward Sapporo 060-0810 Japan
| | - Deju Ye
- State Key Laboratory of Analytical Chemistry for Life Science Chemistry and Biomedicine Innovation Center (ChemBIC) School of Chemistry and Chemical Engineering Nanjing University Nanjing 210023 China
| |
Collapse
|
24
|
Taylor-Williams M, Spicer G, Bale G, Bohndiek SE. Noninvasive hemoglobin sensing and imaging: optical tools for disease diagnosis. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:JBO-220074VR. [PMID: 35922891 PMCID: PMC9346606 DOI: 10.1117/1.jbo.27.8.080901] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/27/2022] [Indexed: 05/08/2023]
Abstract
SIGNIFICANCE Measurement and imaging of hemoglobin oxygenation are used extensively in the detection and diagnosis of disease; however, the applied instruments vary widely in their depth of imaging, spatiotemporal resolution, sensitivity, accuracy, complexity, physical size, and cost. The wide variation in available instrumentation can make it challenging for end users to select the appropriate tools for their application and to understand the relative limitations of different methods. AIM We aim to provide a systematic overview of the field of hemoglobin imaging and sensing. APPROACH We reviewed the sensing and imaging methods used to analyze hemoglobin oxygenation, including pulse oximetry, spectral reflectance imaging, diffuse optical imaging, spectroscopic optical coherence tomography, photoacoustic imaging, and diffuse correlation spectroscopy. RESULTS We compared and contrasted the ability of different methods to determine hemoglobin biomarkers such as oxygenation while considering factors that influence their practical application. CONCLUSIONS We highlight key limitations in the current state-of-the-art and make suggestions for routes to advance the clinical use and interpretation of hemoglobin oxygenation information.
Collapse
Affiliation(s)
- Michaela Taylor-Williams
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Cancer Research UK Cambridge Institute, Cambridge, United Kingdom, United Kingdom
| | - Graham Spicer
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Cancer Research UK Cambridge Institute, Cambridge, United Kingdom, United Kingdom
| | - Gemma Bale
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Electrical Division, Department of Engineering, Cambridge, United Kingdom, United Kingdom
| | - Sarah E Bohndiek
- University of Cambridge, Department of Physics, Cavendish Laboratory, Cambridge, United Kingdom, United Kingdom
- University of Cambridge, Cancer Research UK Cambridge Institute, Cambridge, United Kingdom, United Kingdom
| |
Collapse
|
25
|
Wu L, Zeng W, Ishigaki Y, Zhang J, Bai H, Harimoto T, Suzuki T, Ye D. A Ratiometric Photoacoustic Probe with a Reversible Response to Hydrogen Sulfide and Hydroxyl Radicals for Dynamic Imaging of Liver Inflammation. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202209248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Luyan Wu
- Nanjing University Chemistry CHINA
| | | | | | | | - He Bai
- Nanjing University chemistry CHINA
| | | | | | - Deju Ye
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University Chemistry 163 Xianlin Road, 210023 Nanjing CHINA
| |
Collapse
|
26
|
Kang D. Photoacoustic signal-to-noise ratio comparison for pulse and continuous waveforms of very low optical fluence. JOURNAL OF BIOMEDICAL OPTICS 2022; 27:076006. [PMID: 36451701 PMCID: PMC9321197 DOI: 10.1117/1.jbo.27.7.076006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 07/07/2022] [Indexed: 06/17/2023]
Abstract
SIGNIFICANCE A majority in the photoacoustic (PA) community unconditionally accepts that pulse PA signals show much higher signal-to-noise ratios (SNRs) than continuously excited PA signals. However, we indicate this existing notion would not be valid for very low optical-fluence light-emiting diodes (LEDs)/laser diodes (LDs)-based PA systems. AIM We demonstrate in theory and simulation that when the optical fluence of PA-excitation waveforms is much lower than the American National Standards Institute (ANSI) maximum permission exposure (MPE), matched filtered PA signals from chirp waveforms show higher SNRs than those of pulse train waveforms. APPROACH We theoretically derive the PA SNR expression considering the pulse fluence reduction factor based on the ANSI MPE. We investigate and analyze SNR ratios of the pulse train and chirp-waveform matched filtered PA signals with conceptual understanding. We also perform brute-force simulations to extract PA SNRs for the verification of the result. RESULTS The brute-force simulations show that the matched filtering with chirp waveforms could achieve better SNRs than pulse train waveforms for very low-fluence PA systems. As the fluence is smaller, the SNR of the matched filtered PA signals is more dominant than that of pulse trains in a wider PA data acquisition time range. In addition, estimated SNR ratios adopting actual parameters of LED/LD-based pulse train PA systems in previous literature support the finding of this paper. CONCLUSIONS The result can extend the possibility of applying various continuous waveform techniques already studied in the conventional radar technology to PA systems of limited optical power, which would diversify and expedite the research and development of LED/LD-based, compact, and cost-effective PA systems.
Collapse
Affiliation(s)
- DongYel Kang
- Hanbat National University, School of Basic Sciences, Daejeon, Republic of Korea
| |
Collapse
|
27
|
Shi M, Zhao T, West SJ, Desjardins AE, Vercauteren T, Xia W. Improving needle visibility in LED-based photoacoustic imaging using deep learning with semi-synthetic datasets. PHOTOACOUSTICS 2022; 26:100351. [PMID: 35495095 PMCID: PMC9048160 DOI: 10.1016/j.pacs.2022.100351] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 06/14/2023]
Abstract
Photoacoustic imaging has shown great potential for guiding minimally invasive procedures by accurate identification of critical tissue targets and invasive medical devices (such as metallic needles). The use of light emitting diodes (LEDs) as the excitation light sources accelerates its clinical translation owing to its high affordability and portability. However, needle visibility in LED-based photoacoustic imaging is compromised primarily due to its low optical fluence. In this work, we propose a deep learning framework based on U-Net to improve the visibility of clinical metallic needles with a LED-based photoacoustic and ultrasound imaging system. To address the complexity of capturing ground truth for real data and the poor realism of purely simulated data, this framework included the generation of semi-synthetic training datasets combining both simulated data to represent features from the needles and in vivo measurements for tissue background. Evaluation of the trained neural network was performed with needle insertions into blood-vessel-mimicking phantoms, pork joint tissue ex vivo and measurements on human volunteers. This deep learning-based framework substantially improved the needle visibility in photoacoustic imaging in vivo compared to conventional reconstruction by suppressing background noise and image artefacts, achieving 5.8 and 4.5 times improvements in terms of signal-to-noise ratio and the modified Hausdorff distance, respectively. Thus, the proposed framework could be helpful for reducing complications during percutaneous needle insertions by accurate identification of clinical needles in photoacoustic imaging.
Collapse
Affiliation(s)
- Mengjie Shi
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, United Kingdom
| | - Tianrui Zhao
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, United Kingdom
| | - Simeon J. West
- Department of Anaesthesia, University College Hospital, London NW1 2BU, United Kingdom
| | - Adrien E. Desjardins
- Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London W1 W 7TY, United Kingdom
- Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, United Kingdom
| | - Tom Vercauteren
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, United Kingdom
| | - Wenfeng Xia
- School of Biomedical Engineering and Imaging Sciences, King’s College London, London SE1 7EH, United Kingdom
| |
Collapse
|
28
|
Mantri Y, Dorobek TR, Tsujimoto J, Penny WF, Garimella PS, Jokerst JV. Monitoring peripheral hemodynamic response to changes in blood pressure via photoacoustic imaging. PHOTOACOUSTICS 2022; 26:100345. [PMID: 35295617 PMCID: PMC8918860 DOI: 10.1016/j.pacs.2022.100345] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 02/23/2022] [Accepted: 03/07/2022] [Indexed: 05/18/2023]
Abstract
Chronic wounds and amputations are common in chronic kidney disease patients needing hemodialysis (HD). HD is often complicated by drops in blood pressure (BP) called intra-dialytic hypotension. Whether intra-dialytic hypotension is associated with detectable changes in foot perfusion, a risk factor for wound formation and impaired healing remains unknown. Photoacoustic (PA) imaging is ideally suited to study perfusion changes. We scanned the feet of 20 HD and 11 healthy subjects. HD patients were scanned before and after a dialysis session whereas healthy subjects were scanned twice at rest and once after a 10 min exercise period while BP was elevated. Healthy (r = 0.70, p < 0.0001) and HD subjects (r = 0.43, p < 0.01) showed a significant correlation between PA intensity and systolic BP. Furthermore, HD cohort showed a significantly reduced PA response to changes in BP compared to the healthy controls (p < 0.0001), showing that PA can monitor hemodynamic changes due to changes in BP.
Collapse
Affiliation(s)
- Yash Mantri
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Tyler R. Dorobek
- Department of Nanoengineering, University of California San Diego, La Jolla, CA, USA
| | - Jason Tsujimoto
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - William F. Penny
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Pranav S. Garimella
- Department of Nephrology – Hypertension, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Jesse V. Jokerst
- Department of Nanoengineering, University of California San Diego, La Jolla, CA, USA
- Materials Science Program, University of California San Diego, La Jolla, CA, USA
- Department of Radiology, University of California San Diego, La Jolla, CA, USA
- Correspondence to: University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
| |
Collapse
|
29
|
Mantri Y, Sit I, Zhou J, Grassian VH, Jokerst JV. Photoacoustic Enhancement of Ferricyanide-Treated Silver Chalcogenide-Coated Gold Nanorods. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2022; 126:7605-7614. [PMID: 36249163 PMCID: PMC9563653 DOI: 10.1021/acs.jpcc.2c01727] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Plasmonic gold nanorods (AuNRs) are often employed as photoacoustic (PA) contrast agents due to their ease of synthesis, functionalization, and biocompatibility. These materials can produce activatable signals in response to a change in optical absorbance intensity or absorbance wavelength. Here, we report a surprising finding: Ag2S/Se-coated AuNRs have a ~40-fold PA enhancement upon addition of an oxidant but with no change in absorption spectra. We then study the mechanism underlying this enhancement. Electron micrographs and absorption spectra show good colloidal stability and retention of the core-shell structure after potassium hexacyanoferrate(III) (HCF) addition, ruling out aggregation and morphology-induced PA enhancement. X-ray diffraction data showed no changes, ruling out crystallographic phase changes upon HCF addition, thus leading to induced PA enhancement. Attenuated total reflectance-Fourier transform infrared spectroscopy and zeta potential analysis suggest that PA enhancement is driven by the irreversible displacement of hexadecyltrimethylammonium bromide with HCF. This is further confirmed using elemental mapping with energy-dispersive X-ray analysis. PA characterization after HCF addition showed a four-fold increase in the Grüneisen parameter (Γ), thus resulting in PA enhancement. The PA enhancement is not seen in uncoated AuNRs or spherical particles. Two possible mechanisms for PA enhancement are proposed: first, the photo-induced redox heating at the Ag2S/Se shell-HCF interface, resulting in an increase in temperature-dependent Γ, and second, an enhanced electrostriction response due to HCF adsorption on a layered plasmonic nanoparticle surface, resulting in a high thermal expansion coefficient (β) that is directly proportional to Γ.
Collapse
Affiliation(s)
- Yash Mantri
- Department of Bioengineering, University of California San Diego, La Jolla, California 92093, United States
| | - Izaac Sit
- Department of Nanoengineering, University of California San Diego, La Jolla, California 92093, United States
| | - Jiajing Zhou
- Department of Nanoengineering, University of California San Diego, La Jolla, California 92093, United States
| | - Vicki H Grassian
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093, United States
| | - Jesse V Jokerst
- Department of Nanoengineering, Materials Science Program, and Department of Radiology, University of California San Diego, La Jolla, California 92093, United States
| |
Collapse
|
30
|
Mantri Y, Tsujimoto J, Donovan B, Fernandes CC, Garimella PS, Penny WF, Anderson CA, Jokerst JV. Photoacoustic monitoring of angiogenesis predicts response to therapy in healing wounds. Wound Repair Regen 2022; 30:258-267. [PMID: 34985822 PMCID: PMC8897271 DOI: 10.1111/wrr.12992] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 12/03/2021] [Accepted: 12/24/2021] [Indexed: 12/13/2022]
Abstract
Chronic wounds are a major health problem that cause the medical infrastructure billions of dollars every year. Chronic wounds are often difficult to heal and cause significant discomfort. Although wound specialists have numerous therapeutic modalities at their disposal, tools that could three dimensional-map wound bed physiology and guide therapy do not exist. Visual cues are the current standard but are limited to surface assessment; clinicians rely on experience to predict response to therapy. Photoacoustic (PA) ultrasound (US) is a non-invasive, hybrid imaging modality that can solve these major limitations. PA relies on the contrast generated by haemoglobin in blood which allows it to map local angiogenesis, tissue perfusion and oxygen saturation-all critical parameters for wound healing. This work evaluates the use of PA-US to monitor angiogenesis and stratify patients responding versus not-responding to therapy. We imaged 19 patients with 22 wounds once a week for at least 3 weeks. Our findings suggest that PA imaging directly visualises angiogenesis. Patients responding to therapy showed clear signs of angiogenesis and an increased rate of PA increase (p = 0.002). These responders had a significant and negative correlation between PA intensity and wound size. Hypertension was correlated to impaired angiogenesis in non-responsive patients. The rate of PA increase and hence the rate of angiogenesis was able to predict healing times within 30 days from the start of monitoring (power = 88%, alpha = 0.05). This early response detection system could help inform management and treatment strategies while improving outcomes and reducing costs.
Collapse
Affiliation(s)
- Yash Mantri
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Jason Tsujimoto
- Department of Bioengineering, University of California San Diego, La Jolla, CA, USA
| | - Brian Donovan
- Department of Chemical Engineering, University of California San Diego, La Jolla, CA, USA
| | | | - Pranav S. Garimella
- Division of Nephrology – Hypertension, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - William F. Penny
- Department of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Caesar A. Anderson
- Department of Emergency Medicine, Hyperbaric and Wound Healing Center, University of California San Diego, Encinitas, CA, USA
| | - Jesse V. Jokerst
- Department of Nanoengineering, University of California San Diego, La Jolla, CA, USA.,Materials Science Program, University of California San Diego, La Jolla, CA, USA.,Department of Radiology, University of California San Diego, La Jolla, CA, USA
| |
Collapse
|
31
|
Mantri Y, Tsujimoto J, Penny WF, Garimella PS, Anderson CA, Jokerst JV. Point-of-Care Ultrasound as a Tool to Assess Wound Size and Tissue Regeneration after Skin Grafting. ULTRASOUND IN MEDICINE & BIOLOGY 2021; 47:2550-2559. [PMID: 34210560 PMCID: PMC10041823 DOI: 10.1016/j.ultrasmedbio.2021.05.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 05/06/2021] [Accepted: 05/17/2021] [Indexed: 06/13/2023]
Abstract
Chronic wounds can be difficult to heal and are often accompanied by pain and discomfort. Multiple skin substitutes or cellularized/tissue-based skin products have been used in an attempt to facilitate closure of complex wounds. Allografts from cadaveric sources have been a viable option in achieving such closure. However, early assessment of graft incorporation has been difficult clinically, often with delayed evidence of failure. Visual cues to assess graft integrity have been limited and remain largely superficial at the skin surface. Furthermore, currently used optical imaging techniques can penetrate only a few millimeters deep into tissue. Ultrasound (US) imaging offers a potential solution to address this limitation. This work evaluates the use of US to monitor wound healing and allograft integration. We used a commercially available dual-mode (US and photoacoustic) scanner operating only in US mode. We compared the reported wound size from the clinic with the size measured using US in 45 patients. Two patients from this cohort received an allogenic skin graft and underwent multiple US scans over a 110-d period. All data were processed by two independent analysts; one of them was blinded to the study. We measured change in US intensity and wound contraction as a function of time. Our results revealed a strong correlation (R2 = 0.81, p < 0.0001) between clinically and US-measured wound sizes. Wound contraction >91% was seen in both patients after skin grafting. An inverse relationship between wound size and US intensity (R2 = 0.77, p < 0 .0001) indicated that the echogenicity of the wound bed increases as healthy cells infiltrate the allograft matrix, regenerating and leading to healthy tissue and re-epithelization. This work indicates that US can be used to measure wound size and visualize tissue regeneration during the healing process.
Collapse
Affiliation(s)
- Yash Mantri
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - Jason Tsujimoto
- Department of Bioengineering, University of California San Diego, La Jolla, California, USA
| | - William F Penny
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Pranav S Garimella
- Division of Nephrology-Hypertension, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Caesar A Anderson
- Department of Emergency Medicine, Hyperbaric Medicine and Wound Healing Center, University of California San Diego, Encinitas, California, USA
| | - Jesse V Jokerst
- Department of NanoEngineering, University of California San Diego, La Jolla, California, USA; Materials Science Program, University of California San Diego, La Jolla, California, USA; Department of Radiology, University of California San Diego, La Jolla, California, USA.
| |
Collapse
|
32
|
Palma-Chavez J, Pfefer TJ, Agrawal A, Jokerst JV, Vogt WC. Review of consensus test methods in medical imaging and current practices in photoacoustic image quality assessment. JOURNAL OF BIOMEDICAL OPTICS 2021; 26:JBO-210176VSSR. [PMID: 34510850 PMCID: PMC8434148 DOI: 10.1117/1.jbo.26.9.090901] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 08/17/2021] [Indexed: 05/06/2023]
Abstract
SIGNIFICANCE Photoacoustic imaging (PAI) is a powerful emerging technology with broad clinical applications, but consensus test methods are needed to standardize performance evaluation and accelerate translation. AIM To review consensus image quality test methods for mature imaging modalities [ultrasound, magnetic resonance imaging (MRI), x-ray CT, and x-ray mammography], identify best practices in phantom design and testing procedures, and compare against current practices in PAI phantom testing. APPROACH We reviewed scientific papers, international standards, clinical accreditation guidelines, and professional society recommendations describing medical image quality test methods. Observations are organized by image quality characteristics (IQCs), including spatial resolution, geometric accuracy, imaging depth, uniformity, sensitivity, low-contrast detectability, and artifacts. RESULTS Consensus documents typically prescribed phantom geometry and material property requirements, as well as specific data acquisition and analysis protocols to optimize test consistency and reproducibility. While these documents considered a wide array of IQCs, reported PAI phantom testing focused heavily on in-plane resolution, depth of visualization, and sensitivity. Understudied IQCs that merit further consideration include out-of-plane resolution, geometric accuracy, uniformity, low-contrast detectability, and co-registration accuracy. CONCLUSIONS Available medical image quality standards provide a blueprint for establishing consensus best practices for photoacoustic image quality assessment and thus hastening PAI technology advancement, translation, and clinical adoption.
Collapse
Affiliation(s)
- Jorge Palma-Chavez
- University of California San Diego, Department of NanoEngineering, La Jolla, California, United States
| | - T. Joshua Pfefer
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, Maryland, United States
| | - Anant Agrawal
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, Maryland, United States
| | - Jesse V. Jokerst
- University of California San Diego, Department of NanoEngineering, La Jolla, California, United States
- University of California San Diego, Department of Radiology, La Jolla, California, United States
- University of California San Diego, Materials Science and Engineering Program, La Jolla, California, United States
| | - William C. Vogt
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, Maryland, United States
- Address all correspondence to William C. Vogt,
| |
Collapse
|
33
|
Orfanakis M, Tserevelakis GJ, Zacharakis G. A Cost-Efficient Multiwavelength LED-Based System for Quantitative Photoacoustic Measurements. SENSORS 2021; 21:s21144888. [PMID: 34300627 PMCID: PMC8309896 DOI: 10.3390/s21144888] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/30/2021] [Accepted: 07/15/2021] [Indexed: 01/13/2023]
Abstract
The unique ability of photoacoustic (PA) sensing to provide optical absorption information of biomolecules deep inside turbid tissues with high sensitivity has recently enabled the development of various novel diagnostic systems for biomedical applications. In many cases, PA setups can be bulky, complex, and costly, as they typically require the integration of expensive Q-switched nanosecond lasers, and also presents limited wavelength availability. This article presents a compact, cost-efficient, multiwavelength PA sensing system for quantitative measurements, by utilizing two high-power LED sources emitting at central wavelengths of 444 and 628 nm, respectively, and a single-element ultrasonic transducer at 3.5 MHz for signal detection. We investigate the performance of LEDs in pulsed mode and explore the dependence of PA responses on absorber's concentration and applied energy fluence using tissue-mimicking phantoms demonstrating both optical absorption and scattering properties. Finally, we apply the developed system on the spectral unmixing of two absorbers contained at various relative concentrations in the phantoms, to provide accurate estimations with absolute deviations ranging between 0.4 and 12.3%. An upgraded version of the PA system may provide valuable in-vivo multiparametric measurements of important biomarkers, such as hemoglobin oxygenation, melanin concentration, local lipid content, and glucose levels.
Collapse
Affiliation(s)
- Michalis Orfanakis
- Foundation for Research and Technology Hellas, Institute of Electronic Structure and Laser, N. Plastira 100, GR-70013 Heraklion, Greece; (M.O.); (G.J.T.)
- School of Medicine, University of Crete, GR-71003 Heraklion, Greece
| | - George J. Tserevelakis
- Foundation for Research and Technology Hellas, Institute of Electronic Structure and Laser, N. Plastira 100, GR-70013 Heraklion, Greece; (M.O.); (G.J.T.)
| | - Giannis Zacharakis
- Foundation for Research and Technology Hellas, Institute of Electronic Structure and Laser, N. Plastira 100, GR-70013 Heraklion, Greece; (M.O.); (G.J.T.)
- Correspondence:
| |
Collapse
|
34
|
Hariri A, Palma-Chavez J, Wear KA, Pfefer TJ, Jokerst JV, Vogt WC. Polyacrylamide hydrogel phantoms for performance evaluation of multispectral photoacoustic imaging systems. PHOTOACOUSTICS 2021; 22:100245. [PMID: 33747787 PMCID: PMC7972966 DOI: 10.1016/j.pacs.2021.100245] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 12/09/2020] [Accepted: 02/12/2021] [Indexed: 05/21/2023]
Abstract
As photoacoustic imaging (PAI) begins to mature and undergo clinical translation, there is a need for well-validated, standardized performance test methods to support device development, quality control, and regulatory evaluation. Despite recent progress, current PAI phantoms may not adequately replicate tissue light and sound transport over the full range of optical wavelengths and acoustic frequencies employed by reported PAI devices. Here we introduce polyacrylamide (PAA) hydrogel as a candidate material for fabricating stable phantoms with well-characterized optical and acoustic properties that are biologically relevant over a broad range of system design parameters. We evaluated suitability of PAA phantoms for conducting image quality assessment of three PAI systems with substantially different operating parameters including two commercial systems and a custom system. Imaging results indicated that appropriately tuned PAA phantoms are useful tools for assessing and comparing PAI system image quality. These phantoms may also facilitate future standardization of performance test methodology.
Collapse
Affiliation(s)
- Ali Hariri
- Department of NanoEngineering, University of California San Diego, La Jolla, CA 92093, USA
| | - Jorge Palma-Chavez
- Department of NanoEngineering, University of California San Diego, La Jolla, CA 92093, USA
| | - Keith A Wear
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA
| | - T Joshua Pfefer
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA
| | - Jesse V Jokerst
- Department of NanoEngineering, University of California San Diego, La Jolla, CA 92093, USA
- Department of Radiology, University of California San Diego, La Jolla, CA 92093, USA
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA 92093, USA
| | - William C Vogt
- Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA
| |
Collapse
|
35
|
Joseph J, Ajith Singh MK, Sato N, Bohndiek SE. Technical validation studies of a dual-wavelength LED-based photoacoustic and ultrasound imaging system. PHOTOACOUSTICS 2021; 22:100267. [PMID: 33948434 PMCID: PMC8080074 DOI: 10.1016/j.pacs.2021.100267] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 03/01/2021] [Accepted: 04/06/2021] [Indexed: 05/12/2023]
Abstract
Recent advances in high power, pulsed, light emitting diodes (LEDs) have shown potential as fast, robust and relatively inexpensive excitation sources for photoacoustic imaging (PAI), yet systematic characterization of performance for biomedical imaging is still lacking. We report here technical and biological validation studies of a commercial dual-wavelength LED-based PAI and ultrasound system. Phantoms and small animals were used to assess temporal precision. In phantom studies, we found high temporal stability of the LED-based PAI system, with no significant drift in performance observed during 6 h of operation or over 30 days of repeated measurements. In vivo dual-wavelength imaging was able to map the dynamics of changes in blood oxygenation during oxygen-enhanced imaging and reveal the kinetics of indocyanine green contrast agent inflow after intravenous administration (Tmax∼6 min). Taken together, these studies indicate that LED-based excitation could be promising for future application in functional and molecular PAI.
Collapse
Affiliation(s)
- James Joseph
- Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
- Cancer Research UK Cambridge Institute, University of Cambridge, Robinson Way, Cambridge, CB2 0RE, UK
- Now at School of Science and Engineering, Fulton Building, University of Dundee, DD1 4HN, UK
| | | | - Naoto Sato
- Research and Development Division, CYBERDYNE INC, Tsukuba, 305-0818, Japan
| | - Sarah E. Bohndiek
- Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE, UK
- Cancer Research UK Cambridge Institute, University of Cambridge, Robinson Way, Cambridge, CB2 0RE, UK
| |
Collapse
|
36
|
Wiacek A, Lediju Bell MA. Photoacoustic-guided surgery from head to toe [Invited]. BIOMEDICAL OPTICS EXPRESS 2021; 12:2079-2117. [PMID: 33996218 PMCID: PMC8086464 DOI: 10.1364/boe.417984] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/17/2021] [Accepted: 02/18/2021] [Indexed: 05/04/2023]
Abstract
Photoacoustic imaging-the combination of optics and acoustics to visualize differences in optical absorption - has recently demonstrated strong viability as a promising method to provide critical guidance of multiple surgeries and procedures. Benefits include its potential to assist with tumor resection, identify hemorrhaged and ablated tissue, visualize metal implants (e.g., needle tips, tool tips, brachytherapy seeds), track catheter tips, and avoid accidental injury to critical subsurface anatomy (e.g., major vessels and nerves hidden by tissue during surgery). These benefits are significant because they reduce surgical error, associated surgery-related complications (e.g., cancer recurrence, paralysis, excessive bleeding), and accidental patient death in the operating room. This invited review covers multiple aspects of the use of photoacoustic imaging to guide both surgical and related non-surgical interventions. Applicable organ systems span structures within the head to contents of the toes, with an eye toward surgical and interventional translation for the benefit of patients and for use in operating rooms and interventional suites worldwide. We additionally include a critical discussion of complete systems and tools needed to maximize the success of surgical and interventional applications of photoacoustic-based technology, spanning light delivery, acoustic detection, and robotic methods. Multiple enabling hardware and software integration components are also discussed, concluding with a summary and future outlook based on the current state of technological developments, recent achievements, and possible new directions.
Collapse
Affiliation(s)
- Alycen Wiacek
- Department of Electrical and Computer Engineering, 3400 N. Charles St., Johns Hopkins University, Baltimore, MD 21218, USA
| | - Muyinatu A. Lediju Bell
- Department of Electrical and Computer Engineering, 3400 N. Charles St., Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Biomedical Engineering, 3400 N. Charles St., Johns Hopkins University, Baltimore, MD 21218, USA
- Department of Computer Science, 3400 N. Charles St., Johns Hopkins University, Baltimore, MD 21218, USA
| |
Collapse
|
37
|
Cebrecos A, García-Garrigós JJ, Descals A, Jiménez N, Benlloch JM, Camarena F. Beamforming for large-area scan and improved SNR in array-based photoacoustic microscopy. ULTRASONICS 2021; 111:106317. [PMID: 33310407 DOI: 10.1016/j.ultras.2020.106317] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/19/2020] [Accepted: 11/24/2020] [Indexed: 05/11/2023]
Abstract
Beamforming enhances the performance of array-based photoacoustic microscopy (PAM) systems for large-area scan. In this study, we quantify the imaging performance of a large field-of-view optical-resolution photoacoustic-microscopy system using an phased-array detector. The system combines a low-cost pulsed-laser diode with a 128-element linear ultrasound probe. Signal-to-noise ratio (SNR) and generalized contrast-to-noise ratio (gCNR) are quantified using the phased-array detector and applying three beamforming strategies: a no-beamforming method equivalent to a single-element flat transducer, a fixed focus beamforming method that mimics a single-element focused transducer, and a dynamic focus beamforming using a delay-and-sum (DAS) algorithm. The imaging capabilities of the system are demonstrated generating high-resolution images of tissue-mimicking phantoms containing sub-millimetre ink tubes and an ex vivo rabbit's ear. The results show that dynamic focus DAS beamforming increases and homogenizes SNR along 1-cm2 images, reaching values up to 15 dB compared to an unfocused detector and up to 30 dB compared to out-of-focus regions of the fixed focus configuration. Moreover, the obtained values of gCNR using the DAS beamformer indicate an excellent target visibility, both on phantoms and ex vivo. This strategy makes it possible to scan larger surfaces compared to standard configurations using single-element detectors, paving the way for advanced array-based PAM systems.
Collapse
Affiliation(s)
- A Cebrecos
- Instituto de Instrumentación para Imagen Molecular (i3M), Consejo Superior de Investigaciones Científicas (CSIC), Universitat Politècnica de València (UPV), Camino de Vera s/n, 46022, Valencia, Spain.
| | - J J García-Garrigós
- Instituto de Instrumentación para Imagen Molecular (i3M), Consejo Superior de Investigaciones Científicas (CSIC), Universitat Politècnica de València (UPV), Camino de Vera s/n, 46022, Valencia, Spain
| | - A Descals
- Instituto de Instrumentación para Imagen Molecular (i3M), Consejo Superior de Investigaciones Científicas (CSIC), Universitat Politècnica de València (UPV), Camino de Vera s/n, 46022, Valencia, Spain
| | - N Jiménez
- Instituto de Instrumentación para Imagen Molecular (i3M), Consejo Superior de Investigaciones Científicas (CSIC), Universitat Politècnica de València (UPV), Camino de Vera s/n, 46022, Valencia, Spain
| | - J M Benlloch
- Instituto de Instrumentación para Imagen Molecular (i3M), Consejo Superior de Investigaciones Científicas (CSIC), Universitat Politècnica de València (UPV), Camino de Vera s/n, 46022, Valencia, Spain
| | - F Camarena
- Instituto de Instrumentación para Imagen Molecular (i3M), Consejo Superior de Investigaciones Científicas (CSIC), Universitat Politècnica de València (UPV), Camino de Vera s/n, 46022, Valencia, Spain
| |
Collapse
|
38
|
TiO2-Graphene Quantum Dots Nanocomposites for Photocatalysis in Energy and Biomedical Applications. Catalysts 2021. [DOI: 10.3390/catal11030319] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The focus of current research in material science has shifted from “less efficient” single-component nanomaterials to the superior-performance, next-generation, multifunctional nanocomposites. TiO2 is a widely used benchmark photocatalyst with unique physicochemical properties. However, the large bandgap and massive recombination of photogenerated charge carriers limit its overall photocatalytic efficiency. When TiO2 nanoparticles are modified with graphene quantum dots (GQDs), some significant improvements can be achieved in terms of (i) broadening the light absorption wavelengths, (ii) design of active reaction sites, and (iii) control of the electron-hole (e−-h+) recombination. Accordingly, TiO2-GQDs nanocomposites exhibit promising multifunctionalities in a wide range of fields including, but not limited to, energy, biomedical aids, electronics, and flexible wearable sensors. This review presents some important aspects of TiO2-GQDs nanocomposites as photocatalysts in energy and biomedical applications. These include: (1) structural formulations and synthesis methods of TiO2-GQDs nanocomposites; (2) discourse about the mechanism behind the overall higher photoactivities of these nanocomposites; (3) various characterization techniques which can be used to judge the photocatalytic performance of these nanocomposites, and (4) the application of these nanocomposites in biomedical and energy conversion devices. Although some objectives have been achieved, new challenges still exist and hinder the widespread application of these nanocomposites. These challenges are briefly discussed in the Future Scope section of this review.
Collapse
|
39
|
Das D, Sharma A, Rajendran P, Pramanik M. Another decade of photoacoustic imaging. Phys Med Biol 2020; 66. [PMID: 33361580 DOI: 10.1088/1361-6560/abd669] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 12/23/2020] [Indexed: 01/09/2023]
Abstract
Photoacoustic imaging - a hybrid biomedical imaging modality finding its way to clinical practices. Although the photoacoustic phenomenon was known more than a century back, only in the last two decades it has been widely researched and used for biomedical imaging applications. In this review we focus on the development and progress of the technology in the last decade (2010-2020). From becoming more and more user friendly, cheaper in cost, portable in size, photoacoustic imaging promises a wide range of applications, if translated to clinic. The growth of photoacoustic community is steady, and with several new directions researchers are exploring, it is inevitable that photoacoustic imaging will one day establish itself as a regular imaging system in the clinical practices.
Collapse
Affiliation(s)
- Dhiman Das
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, SINGAPORE
| | - Arunima Sharma
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, SINGAPORE
| | - Praveenbalaji Rajendran
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore, SINGAPORE
| | - Manojit Pramanik
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 70 Nanyang Drive, N1.3-B2-11, Singapore, 637457, SINGAPORE
| |
Collapse
|
40
|
Zhou J, Jokerst JV. Photoacoustic imaging with fiber optic technology: A review. PHOTOACOUSTICS 2020; 20:100211. [PMID: 33163358 PMCID: PMC7606844 DOI: 10.1016/j.pacs.2020.100211] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/05/2020] [Accepted: 09/19/2020] [Indexed: 05/03/2023]
Abstract
Photoacoustic imaging (PAI) has achieved remarkable growth in the past few decades since it takes advantage of both optical and ultrasound (US) imaging. In order to better promote the wide clinical applications of PAI, many miniaturized and portable PAI systems have recently been proposed. Most of these systems utilize fiber optic technologies. Here, we overview the fiber optic technologies used in PAI. This paper discusses three different fiber optic technologies: fiber optic light transmission, fiber optic US transmission, and fiber optic US detection. These fiber optic technologies are analyzed in different PAI modalities including photoacoustic microscopy (PAM), photoacoustic computed tomography (PACT), and minimally invasive photoacoustic imaging (MIPAI).
Collapse
Affiliation(s)
- Jingcheng Zhou
- Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92092, USA
| | - Jesse V. Jokerst
- Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92092, USA
- Materials Science and Engineering Program, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92092, USA
- Department of Radiology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92092, USA
- Corresponding author at: Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92092, USA.
| |
Collapse
|
41
|
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.
Collapse
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,
| |
Collapse
|
42
|
Agano T, Awazu K. Effect of Amplifier Gain on Photoacoustic SNR (Signal to Noise Ratio) in an LED-based Photoacoustic Imaging System. Laser Ther 2020; 29:77-85. [PMID: 34248275 DOI: 10.5978/islsm.20-or-09] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 11/14/2018] [Indexed: 11/06/2022]
Abstract
The possibility of using photoacoustic imaging for functional diagnosis has attracted much attention especially in the clinical field. Among such imaging systems, a system, which offers real-time imaging using compact and low-priced LEDs as a light source, has appeared. Compared to solid state lasers, the LED pulse energy was extremely small, so it had been thought that imaging would be extremely difficult, but by adding a pre-amplifier, real time photoacoustic imaging became possible. However the signal-to-noise ratio (SNR) and the amplifier gain needed for making real time imaging possible have remained unclear. The present study was designed to clarify these data. The results showed that, using a tissue phantom and human fingers, an SNR > 4 and amplifier gain > 80dB were required, and demonstrated why making an image without a pre-amplifier had proved difficult.
Collapse
Affiliation(s)
| | - Kunio Awazu
- Graduate School of Engineering, Osaka University
| |
Collapse
|
43
|
Wen H, Tamarov K, Happonen E, Lehto V, Xu W. Inorganic Nanomaterials for Photothermal‐Based Cancer Theranostics. ADVANCED THERAPEUTICS 2020. [DOI: 10.1002/adtp.202000207] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Huang Wen
- Department of Applied Physics University of Eastern Finland Kuopio 70211 Finland
| | - Konstantin Tamarov
- Department of Applied Physics University of Eastern Finland Kuopio 70211 Finland
| | - Emilia Happonen
- Department of Applied Physics University of Eastern Finland Kuopio 70211 Finland
| | - Vesa‐Pekka Lehto
- Department of Applied Physics University of Eastern Finland Kuopio 70211 Finland
| | - Wujun Xu
- Department of Applied Physics University of Eastern Finland Kuopio 70211 Finland
| |
Collapse
|
44
|
von Knorring T, Mogensen M. Photoacoustic tomography for assessment and quantification of cutaneous and metastatic malignant melanoma - A systematic review. Photodiagnosis Photodyn Ther 2020; 33:102095. [PMID: 33188938 DOI: 10.1016/j.pdpdt.2020.102095] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/04/2020] [Accepted: 11/06/2020] [Indexed: 02/08/2023]
Abstract
BACKGROUND Photoacoustic tomography (PAT) is an emerging noninvasive imaging technique combining high sensitivity optical absorption contrast, such as melanin, with high-resolution ultrasound for deep tissue imaging. The ability of PAT to provide real-time images of skin structures at depth has been studied for diagnosis of primary and metastatic malignant melanoma (MM). OBJECTIVE To provide an overview of the rapidly expanding clinical use of PAT for determination of melanoma thickness and architecture, visualization of metastases in lymph nodes and detection of circulating melanoma cells. METHODS Medline, PubMed, EMBASE, Web of Science, Google Scholar, and Cochrane Library were searched for papers using PAT to assess cutaneous malignant melanoma and melanoma metastases in humans or human specimens. RESULTS The research resulted in 14 articles which met the search criteria. CONCLUSIONS Results from current studies suggest that PAT is a promising tool for assessing both primary and metastatic malignant melanoma in the clinic. The potential of PAT to noninvasively visualize tumour boundaries, as well as assist in the evaluation of metastatic status, could facilitate more effective treatment, resulting in better clearance and reducing the need for additional biopsies. However, larger and methodologically sound studies are warranted.
Collapse
Affiliation(s)
- Terese von Knorring
- Department of Dermatology, Bispebjerg University Hospital, University of Copenhagen, Bispebjerg Bakke 23, Copenhagen, 2400, NV, Denmark.
| | - Mette Mogensen
- Department of Dermatology, Bispebjerg University Hospital, University of Copenhagen, Bispebjerg Bakke 23, Copenhagen, 2400, NV, Denmark
| |
Collapse
|
45
|
Kuniyil Ajith Singh M, Xia W. Portable and Affordable Light Source-Based Photoacoustic Tomography. SENSORS (BASEL, SWITZERLAND) 2020; 20:E6173. [PMID: 33138296 PMCID: PMC7663770 DOI: 10.3390/s20216173] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 10/27/2020] [Accepted: 10/28/2020] [Indexed: 12/27/2022]
Abstract
Photoacoustic imaging is a hybrid imaging modality that offers the advantages of optical (spectroscopic contrast) and ultrasound imaging (scalable spatial resolution and imaging depth). This promising modality has shown excellent potential in a wide range of preclinical and clinical imaging and sensing applications. Even though photoacoustic imaging technology has matured in research settings, its clinical translation is not happening at the expected pace. One of the main reasons for this is the requirement of bulky and expensive pulsed lasers for excitation. To accelerate the clinical translation of photoacoustic imaging and explore its potential in resource-limited settings, it is of paramount importance to develop portable and affordable light sources that can be used as the excitation light source. In this review, we focus on the following aspects: (1) the basic theory of photoacoustic imaging; (2) inexpensive light sources and different implementations; and (3) important preclinical and clinical applications, demonstrated using affordable light source-based photoacoustics. The main focus will be on laser diodes and light-emitting diodes as they have demonstrated promise in photoacoustic tomography-the key technological developments in these areas will be thoroughly reviewed. We believe that this review will be a useful opus for both the beginners and experts in the field of biomedical photoacoustic imaging.
Collapse
Affiliation(s)
- Mithun Kuniyil Ajith Singh
- Research and Business Development Division, CYBERDYNE INC., Stationsplein 45, A4.004, 3013 AK Rotterdam, The Netherlands;
| | - Wenfeng Xia
- School of Biomedical Engineering& Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, UK
| |
Collapse
|
46
|
Photoacoustic Imaging as a Tool for Assessing Hair Follicular Organization. SENSORS 2020; 20:s20205848. [PMID: 33081093 PMCID: PMC7602872 DOI: 10.3390/s20205848] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/11/2020] [Accepted: 10/11/2020] [Indexed: 01/13/2023]
Abstract
Follicular unit extraction (FUE) and follicular unit transplantation (FUT) account for 99% of hair transplant procedures. In both cases, it is important for clinicians to characterize follicle density for treatment planning and evaluation. The existing gold-standard is photographic examination. However, this approach is insensitive to subdermal hair and cannot identify follicle orientation. Here, we introduce a fast and non-invasive imaging technique to measure follicle density and angles across regions of varying density. We first showed that hair is a significant source of photoacoustic signal. We then selected regions of low, medium, and high follicle density and showed that photoacoustic imaging can measure the density of follicles even when they are not visible by eye. We performed handheld imaging by sweeping the transducer across the imaging area to generate 3D images via maximum intensity projection. Background signal from the dermis was removed using a skin tracing method. Measurement of follicle density using photoacoustic imaging was highly correlated with photographic determination (R2 = 0.96). Finally, we measured subdermal follicular angles-a key parameter influencing transection rates in FUE.
Collapse
|
47
|
Graham MT, Bell MAL. Photoacoustic Spatial Coherence Theory and Applications to Coherence-Based Image Contrast and Resolution. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2020; 67:2069-2084. [PMID: 32746173 PMCID: PMC8221408 DOI: 10.1109/tuffc.2020.2999343] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The photoacoustic effect relies on optical transmission, which causes thermal expansion and generates acoustic signals. Coherence-based photoacoustic signal processing is often preferred over more traditional signal processing methods due to improved signal-to-noise ratios, imaging depth, and resolution in applications such as cell tracking, blood flow estimation, and imaging. However, these applications lack a theoretical spatial coherence model to support their implementation. In this article, the photoacoustic spatial coherence theory is derived to generate theoretical spatial coherence functions. These theoretical spatial coherence functions are compared with k-Wave simulated data and experimental data from point and circular targets (0.1-12 mm in diameter) with generally good agreement, particularly in the shorter spatial lag region. The derived theory was used to hypothesize and test previously unexplored principles for optimizing photoacoustic short-lag spatial coherence (SLSC) images, including the influence of the incident light profile on photoacoustic spatial coherence functions and associated SLSC image contrast and resolution. Results also confirm previous trends from experimental observations, including changes in SLSC image resolution and contrast as a function of the first M lags summed to create SLSC images. For example, small targets (e.g., <1-4 mm in diameter) can be imaged with larger M values to boost target contrast and resolution, and contrast can be further improved by reducing the illuminating beam to a size that is smaller than the target size. Overall, the presented theory provides a promising foundation to support a variety of coherence-based photoacoustic signal processing methods, and the associated theory-based simulation methods are more straightforward than the existing k-Wave simulation methods for SLSC images.
Collapse
|
48
|
Wan Q, Wang C, Xu K, Kang J, Wu Y, Trivedi SB, Gehlbach P, Boctor E. Ultrasound Signal Detection with Multi-bounce Laser Microphone. IEEE INTERNATIONAL ULTRASONICS SYMPOSIUM : [PROCEEDINGS]. IEEE INTERNATIONAL ULTRASONICS SYMPOSIUM 2020; 2020:10.1109/ius46767.2020.9251499. [PMID: 34306522 PMCID: PMC8305828 DOI: 10.1109/ius46767.2020.9251499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The multi-bounce laser microphone utilizes optical methods to detect the displacement of a gold-covered thin film diaphragm caused by ultrasound signal pressure waves. This sensitive all-optical sensing technique provides new opportunities for advanced ultrasound imaging as it is expected to achieve a higher detection signal-to-noise ratio (SNR) in a broader spectrum, as compared to conventional ultrasonic transducers. The technique does not involve signal time-averaging and the real-time enhancement in detection SNR stems from the amplification of signal strength due to multiple bouncing off the diaphragm. The system was previously developed for detecting acoustic signatures generated by explosives and were limited to lower than 10 kHz in frequency. To demonstrate its feasibility for biomedical imaging applications, preliminary experiments were conducted to show high fidelity detection of ultrasound waves with frequencies ranging from 100 kHz to in excess of 1 MHz. Experimental results are also presented in this work demonstrating the improved detection sensitivity of the multi-bounce laser microphone in detecting ultrasound signals when compared with a commercial Fabry-Perot type optical hydrophone. Furthermore, we also applied the multi-bounce laser microphone to detect photoacoustic signatures emitted by India ink when a LED bar is used as the excitation source without signal averaging.
Collapse
Affiliation(s)
- Qianqian Wan
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, United States
| | - ChenChia Wang
- Brimrose Corporation of America, Baltimore, United States
| | - Keshuai Xu
- Department of Computer Science, Johns Hopkins University, Baltimore, United States
| | - Jeeun Kang
- Department of Computer Science, Johns Hopkins University, Baltimore, United States
| | - Yixuan Wu
- Department of Computer Science, Johns Hopkins University, Baltimore, United States
| | | | - Peter Gehlbach
- Department of Ophthalmology, Johns Hopkins School of Medicine, Baltimore, United States
| | - Emad Boctor
- Department of Radiology, Johns Hopkins School of Medicine, Baltimore, United States
| |
Collapse
|
49
|
Xavierselvan M, Singh MKA, Mallidi S. In Vivo Tumor Vascular Imaging with Light Emitting Diode-Based Photoacoustic Imaging System. SENSORS (BASEL, SWITZERLAND) 2020; 20:E4503. [PMID: 32806575 PMCID: PMC7472236 DOI: 10.3390/s20164503] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/07/2020] [Accepted: 08/08/2020] [Indexed: 12/13/2022]
Abstract
Photoacoustic (PA) imaging has shown tremendous promise for imaging tumor vasculature and its function at deeper penetration depths without the use of exogenous contrast agents. Traditional PA imaging systems employ expensive and bulky class IV lasers with low pulse repetition rate, due to which its availability for preclinical cancer research is hampered. In this study, we evaluated the capability of a Light-Emitting Diode (LED)-based PA and ultrasound (US) imaging system for monitoring heterogeneous microvasculature in tumors (up to 10 mm in depth) and quantitatively compared the PA images with gold standard histology images. We used a combination of a 7 MHz linear array US transducer and 850 nm excitation wavelength LED arrays to image blood vessels in a subcutaneous tumor model. After imaging, the tumors were sectioned and stained for endothelial cells to correlate with PA images across similar cross-sections. Analysis of 30 regions of interest in tumors from different mice showed a statistically significant R-value of 0.84 where the areas with high blood vessel density had high PA response while low blood vessel density regions had low PA response. Our results confirm that LED-based PA and US imaging can provide 2D and 3D images of tumor vasculature and the potential it has as a valuable tool for preclinical cancer research.
Collapse
Affiliation(s)
- Marvin Xavierselvan
- Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA;
| | - Mithun Kuniyil Ajith Singh
- Research & Business Development Division, Cyberdyne INC, Cambridge Innovation Center, 3013 Rotterdam, The Netherlands;
| | - Srivalleesha Mallidi
- Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA;
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| |
Collapse
|
50
|
Kuriakose M, Nguyen CD, Kuniyil Ajith Singh M, Mallidi S. Optimizing Irradiation Geometry in LED-Based Photoacoustic Imaging with 3D Printed Flexible and Modular Light Delivery System. SENSORS 2020; 20:s20133789. [PMID: 32640683 PMCID: PMC7374354 DOI: 10.3390/s20133789] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/29/2020] [Accepted: 06/29/2020] [Indexed: 01/04/2023]
Abstract
Photoacoustic (PA) imaging–a technique combining the ability of optical imaging to probe functional properties of the tissue and deep structural imaging ability of ultrasound–has gained significant popularity in the past two decades for its utility in several biomedical applications. More recently, light-emitting diodes (LED) are being explored as an alternative to bulky and expensive laser systems used in PA imaging for their portability and low-cost. Due to the large beam divergence of LEDs compared to traditional laser beams, it is imperative to quantify the angular dependence of LED-based illumination and optimize its performance for imaging superficial or deep-seated lesions. A custom-built modular 3-D printed hinge system and tissue-mimicking phantoms with various absorption and scattering properties were used in this study to quantify the angular dependence of LED-based illumination. We also experimentally calculated the source divergence of the pulsed-LED arrays to be 58° ± 8°. Our results from point sources (pencil lead phantom) in non-scattering medium obey the cotangential relationship between the angle of irradiation and maximum PA intensity obtained at various imaging depths, as expected. Strong dependence on the angle of illumination at superficial depths (−5°/mm at 10 mm) was observed that becomes weaker at intermediate depths (−2.5°/mm at 20 mm) and negligible at deeper locations (−1.1°/mm at 30 mm). The results from the tissue-mimicking phantom in scattering media indicate that angles between 30–75° could be used for imaging lesions at various depths (12 mm–28 mm) where lower LED illumination angles (closer to being parallel to the imaging plane) are preferable for deep tissue imaging and superficial lesion imaging is possible with higher LED illumination angles (closer to being perpendicular to the imaging plane). Our results can serve as a priori knowledge for the future LED-based PA system designs employed for both preclinical and clinical applications.
Collapse
Affiliation(s)
- Maju Kuriakose
- Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA; (M.K.); (C.D.N.)
| | - Christopher D. Nguyen
- Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA; (M.K.); (C.D.N.)
| | | | - Srivalleesha Mallidi
- Department of Biomedical Engineering, Tufts University, Medford, MA 02155, USA; (M.K.); (C.D.N.)
- Correspondence:
| |
Collapse
|