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Ding N, Jiang H, Xiang B, Yu Y, Ji C, Liu J, Zhao Y, Luan J, Yang Y, Wang Y, Ma Z. Probe fusion all-optic OCT-PAM dual-mode imaging system for biomedical imaging. PHOTOACOUSTICS 2024; 38:100631. [PMID: 39055738 PMCID: PMC11269793 DOI: 10.1016/j.pacs.2024.100631] [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: 04/25/2024] [Revised: 05/29/2024] [Accepted: 06/28/2024] [Indexed: 07/27/2024]
Abstract
We proposed a non-contact photoacoustic (PA) detection method using spectral domain optical coherence tomography (SDOCT). Two interference spectrums (A-lines) were acquired before and after the PA excitation with SDOCT. PA signal propagated within the sample causing the vibration. The vibration inner the sample introduced phase change between the acquired two A-lines. Thus, the PA signal can be detected by evaluating the difference in phase between the two A-lines. Based on the method, an OCT-PAM dual-mode imaging system was constructed. In the system, SDOCT served as the detection unit for PAM. Thus, the combination of the two imaging modalities was simplified. Another advantage of the system is that it realizes non-contact all-optic detection, which is attractive for biomedical imaging. Using the system, we imaged phantoms of carbon fibers, asparagus leaves and human hairs. Furthermore, the cortical vasculature of rat was imaged in vivo and the flow status was evaluated quantitatively.
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Affiliation(s)
- Ning Ding
- College of Information Science and Engineering, Northeastern University, Shenyang 110819, China
| | - Huiwen Jiang
- College of Information Science and Engineering, Northeastern University, Shenyang 110819, China
| | - Ben Xiang
- College of Information Science and Engineering, Northeastern University, Shenyang 110819, China
| | - Yao Yu
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, china
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao 066004, China
| | - Cheng Ji
- Qinhuangdao Haigang Hospital, Qinhuangdao 066004, China
| | - Jian Liu
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, china
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao 066004, China
| | - Yuqian Zhao
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, china
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao 066004, China
| | - Jingmin Luan
- School of Computer and Communication Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Yanqiu Yang
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, china
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao 066004, China
| | - Yi Wang
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, china
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao 066004, China
| | - Zhenhe Ma
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, china
- Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology, Qinhuangdao 066004, China
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Tamura K, Hashimoto KY, Okawa S. Thermoelastic wave generation and its longitudinal wave propagation measurement by a microscopic optical interferometer. ULTRASONICS 2024; 141:107319. [PMID: 38688112 DOI: 10.1016/j.ultras.2024.107319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 12/15/2023] [Accepted: 04/16/2024] [Indexed: 05/02/2024]
Abstract
Laser ultrasonics is a noncontact measurement method that uses a laser-induced elastic wave source in combination with an optical surface displacement-tracking system. This study compared the performances of two optical interferometers with different characteristics when applied to measurement of pulsed thermoelastic waves. The surface displacement-tracking system was designed to measure the center of the microscopic view. A pulsed laser beam irradiated a black ink layer to generate the thermoelastic waves. The out-of-plane displacement on the axially opposite side was then measured using either a Michelson interferometer or a Sagnac interferometer. The objective lens of the system was of a type commonly used in biological observations. The Michelson interferometer estimated a maximum displacement of 0.43 nm and a maximum sound pressure of 24.7 kPa. The signal-to-noise ratios from 16 averages were 14.9 dB (Michelson interferometer) and 19.2 dB (Sagnac interferometer). Furthermore, this paper compares the performance of the numerically estimated Sagnac interferometer outputs calculated from the measured Michelson interferometer outputs with the experimentally obtained Sagnac interferometer outputs. The numerically estimated Sagnac interferometer's output was shown to be identical to the experimentally acquired output. The Michelson interferometer requires a higher average operating frequency (i.e., it needs a longer data acquisition time), although this interferometer does offer superior displacement output linearity. This property enables calculation of the sound pressure from the displacement amplitude. These findings indicated that combination of the measurement points of the Sagnac interferometer with those of the sparsely distributed Michelson interferometer reduced the measurement time when compared with a single use of the Michelson interferometer while also maintaining the data acquisition quality.
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Affiliation(s)
- Kazuki Tamura
- Hamamatsu University School of Medicine, 1-20-1 Handayama, Chuo-ku, Hamamatsu city, Shizuoka 431-3192, Japan.
| | - Ken-Ya Hashimoto
- University of Electronic Science and Technology of China, 2006 Xiyuan Ave., West High-Tech Zone, Chengdu-city, Sichuan 611731, PR China
| | - Shinpei Okawa
- Hamamatsu University School of Medicine, 1-20-1 Handayama, Chuo-ku, Hamamatsu city, Shizuoka 431-3192, Japan
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Zhu L, Cao H, Ma J, Wang L. Optical ultrasound sensors for photoacoustic imaging: a review. JOURNAL OF BIOMEDICAL OPTICS 2024; 29:S11523. [PMID: 38303991 PMCID: PMC10831871 DOI: 10.1117/1.jbo.29.s1.s11523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 01/08/2024] [Accepted: 01/10/2024] [Indexed: 02/03/2024]
Abstract
Significance Photoacoustic (PA) imaging is an emerging biomedical imaging modality that can map optical absorption contrast in biological tissues by detecting ultrasound signal. Piezoelectric transducers are commonly used in PA imaging to detect the ultrasound signals. However, piezoelectric transducers suffer from low sensitivity when the dimensions are reduced and are easily influenced by electromagnetic interference. To avoid these limitations, various optical ultrasound sensors have been developed and shown their great potential in PA imaging. Aim Our study aims to summarize recent progress in optical ultrasound sensor technologies and their applications in PA imaging. Approach The commonly used optical ultrasound sensing techniques and their applications in PA systems are reviewed. The technical advances of different optical ultrasound sensors are summarized. Results Optical ultrasound sensors can provide wide bandwidth and improved sensitivity with miniatured size, which enables their applications in PA imaging. Conclusions The optical ultrasound sensors are promising transducers in PA imaging to provide higher-resolution images and can be used in new applications with their unique advantages.
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Affiliation(s)
- Liying Zhu
- City University of Hong Kong, Department of Biomedical Engineering, Kowloon, Hong Kong, China
| | - Hongming Cao
- City University of Hong Kong, Department of Biomedical Engineering, Kowloon, Hong Kong, China
| | - Jun Ma
- Nanfang Hospital, Southern Medical University, Department of Burns, Guangzhou, China
| | - Lidai Wang
- City University of Hong Kong, Department of Biomedical Engineering, Kowloon, Hong Kong, China
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Mignanelli L, Schewe M, Rembe C. Model validation and prediction of photoacoustic tumor detection with LDV. SENSING AND BIO-SENSING RESEARCH 2022. [DOI: 10.1016/j.sbsr.2022.100531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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5
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Li D, Tao C, Hu Z, Zhang Z, Liu X. Local-flexible coupling optical-resolution photoacoustic microscopy with enhanced sensitivity. OPTICS LETTERS 2022; 47:3515-3518. [PMID: 35838717 DOI: 10.1364/ol.457652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 06/24/2022] [Indexed: 06/15/2023]
Abstract
An acoustic coupling scheme largely determines the performance of optical-resolution photoacoustic microscopy (OR-PAM), including practicability, sensitivity, and stability. In this study, we propose OR-PAM based on a local-flexible acoustic coupling scheme, which includes a well-designed combiner connecting a set of circulating systems. The combiner integrates an objective lens and an ultrasonic transducer, controls the water level, restricts the flow rate, and drains bubbles. The circulating system provides sustained and steady flowing water. The flowing water constrained in the combiner and the circulating system forms a flexible and stable local contact between the sample and the transducer. Phantom experiments demonstrate that the proposed method can maintain high optical resolution but improve the detection sensitivity by approximately 1.9 times in comparison to dry coupling. In vivo imaging experiments of the mouse eyeground are conducted to examine the practicability of the proposed system in biomedicine. Moreover, in vivo experiments show that OR-PAM based on local-flexible coupling can reveal more details of eyeground microvasculatures, benefiting from its enhanced sensitivity. These merits promise that OR-PAM based on local-flexible coupling may have broad applications in biomedical fields.
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Ma Z, Ding N, Li Z, Zhu K, Li A, Lin Z, Wang Y, Zhao Y, Yu Y, Luan J, Zhu X, Liu J. Spectral interference contrast based non-contact photoacoustic microscopy realized by SDOCT. OPTICS LETTERS 2022; 47:2895-2898. [PMID: 35648958 DOI: 10.1364/ol.458383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 05/15/2022] [Indexed: 06/15/2023]
Abstract
We introduce a method to extract the photoacoustic (PA) signal from a contrast reduction of the interference spectrum acquired by spectral domain optical coherence tomography (SDOCT). This all-optical detection is achieved in a noncontact manner directly on the water surface covered on the sample by using its specular reflection. During SDOCT exposure, the phase of the interference spectrum keeps shaking according to the water surface vibration induced by PA excitation. This results in an interference contrast reduction which is quantified by a fast Fourier transform (FFT) for PA imaging. A tungsten filament, asparagus fern leaf, and mouse auricle are imaged to demonstrate the method.
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Thréard T, de Lima Savi E, Avanesyan S, Chigarev N, Hua Z, Tournat V, Gusev VE, Hurley DH, Raetz S. Photoacoustic 3-D imaging of polycrystalline microstructure improved with transverse acoustic waves. PHOTOACOUSTICS 2021; 23:100286. [PMID: 34430200 PMCID: PMC8371231 DOI: 10.1016/j.pacs.2021.100286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 07/13/2021] [Accepted: 07/15/2021] [Indexed: 05/04/2023]
Abstract
Non-invasive fast imaging of grain microstructure of polycrystalline ceria with sub-micrometric spatial resolution is performed via time-domain Brillouin scattering. The propagation of a nanoacoustic pulse is monitored down to 8 μm deep in a 30 × 30 μm2 area. Grains boundaries are reconstructed in three-dimensions via a two-step processing method, relying on the wavelet synchro-squeezed transform and the alphashape algorithm. Imaging contrast is improved by taking advantage of stronger sensitivity to anisotropy of transverse acoustic waves, compared with longitudinal waves. Utilization of transverse waves in the image processing reveals additional boundaries, confirmed by an electron backscattering diffraction pattern but not discerned using longitudinal waves. A buried inclined interface between differently oriented grains is identified by monitoring changes in amplitude (phase) of the portion of the signal associated with transverse (longitudinal) waves. Estimates of the inclination angle of this interface prove the sensitivity of our laser ultrasonic method to image inclined boundaries.
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Affiliation(s)
- Théo Thréard
- Laboratoire d’Acoustique de l’Université du Mans (LAUM), UMR 6613, Institut d’Acoustique – Graduate School (IA-GS), CNRS, Le Mans Université, France
| | - Elton de Lima Savi
- Laboratoire d’Acoustique de l’Université du Mans (LAUM), UMR 6613, Institut d’Acoustique – Graduate School (IA-GS), CNRS, Le Mans Université, France
| | - Sergey Avanesyan
- Departement of Life and Physical Sciences, Fisk University, Nashville, USA
| | - Nikolay Chigarev
- Laboratoire d’Acoustique de l’Université du Mans (LAUM), UMR 6613, Institut d’Acoustique – Graduate School (IA-GS), CNRS, Le Mans Université, France
| | - Zilong Hua
- Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415, USA
| | - Vincent Tournat
- Laboratoire d’Acoustique de l’Université du Mans (LAUM), UMR 6613, Institut d’Acoustique – Graduate School (IA-GS), CNRS, Le Mans Université, France
| | - Vitalyi E. Gusev
- Laboratoire d’Acoustique de l’Université du Mans (LAUM), UMR 6613, Institut d’Acoustique – Graduate School (IA-GS), CNRS, Le Mans Université, France
| | - David H. Hurley
- Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415, USA
| | - Samuel Raetz
- Laboratoire d’Acoustique de l’Université du Mans (LAUM), UMR 6613, Institut d’Acoustique – Graduate School (IA-GS), CNRS, Le Mans Université, France
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8
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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.
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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
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Chen L, Zeng G, Guo D, Liu J, Zhang X, Lin S, Zhang K. Soft elastic hydrogel couplants for ultrasonography. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 119:111609. [PMID: 33321653 DOI: 10.1016/j.msec.2020.111609] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 09/11/2020] [Accepted: 10/05/2020] [Indexed: 12/19/2022]
Abstract
Couplants play significant roles in ultrasonography. To ensure imaging quality, it is critical to maintain conformal contact of the couplant with both the skin surface and the ultrasound probe in clinical applications. In addition, either the probe or the couplant should not deform the skin surface significantly, which will result in an overestimated modulus of the tissue for elastography imaging. However, existing liquid gel couplants cannot bear external compressive force, while existing solid gel couplants cannot maintain a conformal contact with skin surface. Especially, the nonconformal contacts and deformation become more severe on body parts of locally high curvatures such as skin tumors, fingers, and elbows. Here we report a bilayer design of couplant for ultrasonography, composing of a stiff layer and a compliant layer of hydrogels. The bilayer hydrogel pad enables it to bear external compression, allowing the probe to move smoothly, conforming high curvature parts and releasing stress concentration. Our clinical experiments further show high quality imaging of thyroid nodules, skin tumors in elbows and fingers using the bilayer hydrogel pad, which represents a promising alternative for a range of applications in ultrasonic diagnosis.
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Affiliation(s)
- Luzeng Chen
- Department of Ultrasonography, Peking University First Hospital, Beijing 100081, China
| | - Guangzhi Zeng
- School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Dengke Guo
- School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Jinghua Liu
- Department of Ultrasonography, Peking University First Hospital, Beijing 100081, China
| | - Xiang Zhang
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Shaoting Lin
- Soft Active Materials Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Kai Zhang
- School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081, China.
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10
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Hosseinaee Z, Le M, Bell K, Reza PH. Towards non-contact photoacoustic imaging [review]. PHOTOACOUSTICS 2020; 20:100207. [PMID: 33024694 PMCID: PMC7530308 DOI: 10.1016/j.pacs.2020.100207] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/29/2020] [Accepted: 07/10/2020] [Indexed: 05/06/2023]
Abstract
Photoacoustic imaging (PAI) takes advantage of both optical and ultrasound imaging properties to visualize optical absorption with high resolution and contrast. Photoacoustic microscopy (PAM) is usually categorized with all-optical microscopy techniques such as optical coherence tomography or confocal microscopes. Despite offering high sensitivity, novel imaging contrast, and high resolution, PAM is not generally an all-optical imaging method unlike the other microscopy techniques. One of the significant limitations of photoacoustic microscopes arises from their need to be in physical contact with the sample through a coupling media. This physical contact, coupling, or immersion of the sample is undesirable or impractical for many clinical and pre-clinical applications. This also limits the flexibility of photoacoustic techniques to be integrated with other all-optical imaging microscopes for providing complementary imaging contrast. To overcome these limitations, several non-contact photoacoustic signal detection approaches have been proposed. This paper presents a brief overview of current non-contact photoacoustic detection techniques with an emphasis on all-optical detection methods and their associated physical mechanisms.
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Affiliation(s)
- Zohreh Hosseinaee
- PhotoMedicine Labs, Department of System Design Engineering, University of Waterloo, Ontario, N2L 3G1, Canada
| | - Martin Le
- PhotoMedicine Labs, Department of System Design Engineering, University of Waterloo, Ontario, N2L 3G1, Canada
| | - Kevan Bell
- PhotoMedicine Labs, Department of System Design Engineering, University of Waterloo, Ontario, N2L 3G1, Canada
- IllumiSonics Inc., Department of Systems Design Engineering, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada
| | - Parsin Haji Reza
- PhotoMedicine Labs, Department of System Design Engineering, University of Waterloo, Ontario, N2L 3G1, Canada
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11
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Wang Y, Hu Y, Peng B, Zhou H, Zhao Y, Ma Z. Complete-noncontact photoacoustic microscopy by detection of initial pressures using a 3×3 coupler-based fiber-optic interferometer. BIOMEDICAL OPTICS EXPRESS 2020; 11:505-516. [PMID: 32010531 PMCID: PMC6968767 DOI: 10.1364/boe.381129] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/11/2019] [Accepted: 12/19/2019] [Indexed: 05/08/2023]
Abstract
We demonstrate a 3×3 coupler-based fiber-optic interferometric system to detect the local initial photoacoustic pressure. In contrast with the existing interferometric photoacoustic microscopy (PAM) relying on the measurement of the phase change of the probe light caused by the sample surface vibration, the present method measures the intensity change of the probe light caused by the initial photoacoustic pressure. Compared with the conventional interferometric PAMs, this method has the advantages: (1) it is free from the influence of the rough tissue surface, achieving complete noncontact in vivo imaging; (2) the probe light and the excitation light are focused at a same point below the sample surface, and the confocal configuration makes it more convenient for in vivo imaging; and (3) there is no need for phase stabilization, allowing a high imaging speed. These advantages show that the method will be a promising technique for in vivo imaging. This method is verified by imaging of a resolution test target and in vivo imaging of the blood vessels in a mouse ear.
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Affiliation(s)
- Yi Wang
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Yingxin Hu
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Binyang Peng
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Hongxian Zhou
- Experiment Education Center, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Yuqian Zhao
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Zhenhe Ma
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
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12
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Singhvi A, Boyle KC, Fallahpour M, Khuri-Yakub BT, Arbabian A. A Microwave-Induced Thermoacoustic Imaging System With Non-Contact Ultrasound Detection. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2019; 66:1587-1599. [PMID: 31251184 DOI: 10.1109/tuffc.2019.2925592] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Portable and easy-to-use imaging systems are in high demand for medical, security screening, nondestructive testing, and sensing applications. We present a new microwave-induced thermoacoustic imaging system with non-contact, airborne ultrasound (US) detection. In this system, a 2.7 GHz microwave excitation causes differential heating at interfaces with dielectric contrast, and the resulting US signal via the thermoacoustic effect travels out of the sample to the detector in air at a standoff. The 65 dB interface loss due to the impedance mismatch at the air-sample boundary is overcome with high-sensitivity capacitive micromachined ultrasonic transducers with minimum detectable pressures (MDPs) as low as 278 μ Pa rms and we explore two different designs-one operating at a center frequency of 71 kHz and another at a center frequency of 910 kHz. We further demonstrate that the air-sample interface presents a tradeoff with the advantage of improved resolution, as the change in wave velocity at the interface creates a strong focusing effect alongside the attenuation, resulting in axial resolutions more than 10× smaller than that predicted by the traditional speed/bandwidth limit. A piecewise synthetic aperture radar (SAR) algorithm modified for US imaging and enhanced with signal processing techniques is used for image reconstruction, resulting in mm-scale lateral and axial image resolution. Finally, measurements are conducted to verify simulations and demonstrate successful system performance.
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13
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Vu T, Razansky D, Yao J. Listening to tissues with new light: recent technological advances in photoacoustic imaging. JOURNAL OF OPTICS (2010) 2019; 21:10.1088/2040-8986/ab3b1a. [PMID: 32051756 PMCID: PMC7015182 DOI: 10.1088/2040-8986/ab3b1a] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Photoacoustic tomography (PAT), or optoacoustic tomography, has achieved remarkable progress in the past decade, benefiting from the joint developments in optics, acoustics, chemistry, computing and mathematics. Unlike pure optical or ultrasound imaging, PAT can provide unique optical absorption contrast as well as widely scalable spatial resolution, penetration depth and imaging speed. Moreover, PAT has inherent sensitivity to tissue's functional, molecular, and metabolic state. With these merits, PAT has been applied in a wide range of life science disciplines, and has enabled biomedical research unattainable by other imaging methods. This Review article aims at introducing state-of-the-art PAT technologies and their representative applications. The focus is on recent technological breakthroughs in structural, functional, molecular PAT, including super-resolution imaging, real-time small-animal whole-body imaging, and high-sensitivity functional/molecular imaging. We also discuss the remaining challenges in PAT and envisioned opportunities.
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Affiliation(s)
- Tri Vu
- Photoacoustic Imaging Lab, Department of Biomedical Engineering, Duke University, Durham, NC, USA
| | - Daniel Razansky
- Faculty of Medicine and Institute of Pharmacology and Toxicology, University of Zurich, Switzerland
- Institute for Biomedical Engineering and Department of Information Technology and Electrical Engineering, ETH Zurich, Switzerland
| | - Junjie Yao
- Photoacoustic Imaging Lab, Department of Biomedical Engineering, Duke University, Durham, NC, USA
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Jeon S, Kim J, Lee D, Baik JW, Kim C. Review on practical photoacoustic microscopy. PHOTOACOUSTICS 2019; 15:100141. [PMID: 31463194 PMCID: PMC6710377 DOI: 10.1016/j.pacs.2019.100141] [Citation(s) in RCA: 137] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 06/19/2019] [Accepted: 07/24/2019] [Indexed: 05/03/2023]
Abstract
Photoacoustic imaging (PAI) has many interesting advantages, such as deep imaging depth, high image resolution, and high contrast to intrinsic and extrinsic chromophores, enabling morphological, functional, and molecular imaging of living subjects. Photoacoustic microscopy (PAM) is one form of the PAI inheriting its characteristics and is useful in both preclinical and clinical research. Over the years, PAM systems have been evolved in several forms and each form has its relative advantages and disadvantages. Thus, to maximize the benefits of PAM for a specific application, it is important to configure the PAM system optimally by targeting a specific application. In this review, we provide practical methods for implementing a PAM system to improve the resolution, signal-to-noise ratio (SNR), and imaging speed. In addition, we review the preclinical and the clinical applications of PAM and discuss the current challenges and the scope for future developments.
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Affiliation(s)
| | | | | | | | - Chulhong Kim
- Department of Creative IT Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
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Steinberg I, Huland DM, Vermesh O, Frostig HE, Tummers WS, Gambhir SS. Photoacoustic clinical imaging. PHOTOACOUSTICS 2019; 14:77-98. [PMID: 31293884 PMCID: PMC6595011 DOI: 10.1016/j.pacs.2019.05.001] [Citation(s) in RCA: 277] [Impact Index Per Article: 55.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 04/09/2019] [Accepted: 05/30/2019] [Indexed: 05/18/2023]
Abstract
Photoacoustic is an emerging biomedical imaging modality, which allows imaging optical absorbers in the tissue by acoustic detectors (light in - sound out). Such a technique has an immense potential for clinical translation since it allows high resolution, sufficient imaging depth, with diverse endogenous and exogenous contrast, and is free from ionizing radiation. In recent years, tremendous developments in both the instrumentation and imaging agents have been achieved. These opened avenues for clinical imaging of various sites allowed applications such as brain functional imaging, breast cancer screening, diagnosis of psoriasis and skin lesions, biopsy and surgery guidance, the guidance of tumor therapies at the reproductive and urological systems, as well as imaging tumor metastases at the sentinel lymph nodes. Here we survey the various clinical and pre-clinical literature and discuss the potential applications and hurdles that still need to be overcome.
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Affiliation(s)
- Idan Steinberg
- Department of Radiology, At Stanford University, School of Medicine, Stanford, CA, United States
- Department of Bioengineering, At Stanford University, School of Medicine, Stanford, CA, United States
| | - David M. Huland
- Department of Radiology, At Stanford University, School of Medicine, Stanford, CA, United States
- Molecular Imaging Program at Stanford, Canary Center at Stanford for Cancer Early Detection, At Stanford University, School of Medicine, Stanford, CA, United States
| | - Ophir Vermesh
- Department of Radiology, At Stanford University, School of Medicine, Stanford, CA, United States
- Molecular Imaging Program at Stanford, Canary Center at Stanford for Cancer Early Detection, At Stanford University, School of Medicine, Stanford, CA, United States
| | - Hadas E. Frostig
- Department of Radiology, At Stanford University, School of Medicine, Stanford, CA, United States
- Molecular Imaging Program at Stanford, Canary Center at Stanford for Cancer Early Detection, At Stanford University, School of Medicine, Stanford, CA, United States
| | - Willemieke S. Tummers
- Department of Radiology, At Stanford University, School of Medicine, Stanford, CA, United States
- Molecular Imaging Program at Stanford, Canary Center at Stanford for Cancer Early Detection, At Stanford University, School of Medicine, Stanford, CA, United States
| | - Sanjiv S. Gambhir
- Department of Radiology, At Stanford University, School of Medicine, Stanford, CA, United States
- Department of Bioengineering, At Stanford University, School of Medicine, Stanford, CA, United States
- Department of Materials Science & Engineering, At Stanford University, School of Medicine, Stanford, CA, United States
- Molecular Imaging Program at Stanford, Canary Center at Stanford for Cancer Early Detection, At Stanford University, School of Medicine, Stanford, CA, United States
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16
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Zhang X, Fincke JR, Wynn CM, Johnson MR, Haupt RW, Anthony BW. Full noncontact laser ultrasound: first human data. LIGHT, SCIENCE & APPLICATIONS 2019; 8:119. [PMID: 31885865 PMCID: PMC6923376 DOI: 10.1038/s41377-019-0229-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 11/25/2019] [Accepted: 11/27/2019] [Indexed: 05/23/2023]
Abstract
Full noncontact laser ultrasound (LUS) imaging has several distinct advantages over current medical ultrasound (US) technologies: elimination of the coupling mediums (gel/water), operator-independent image quality, improved repeatability, and volumetric imaging. Current light-based ultrasound utilizing tissue-penetrating photoacoustics (PA) generally uses traditional piezoelectric transducers in contact with the imaged tissue or carries an optical fiber detector close to the imaging site. Unlike PA, the LUS design presented here minimizes the optical penetration and specifically restricts optical-to-acoustic energy transduction at the tissue surface, maximizing the generated acoustic source amplitude. With an appropriate optical design and interferometry, any exposed tissue surfaces can become viable acoustic sources and detectors. LUS operates analogously to conventional ultrasound but uses light instead of piezoelectric elements. Here, we present full noncontact LUS results, imaging targets at ~5 cm depths and at a meter-scale standoff from the target surface. Experimental results demonstrating volumetric imaging and the first LUS images on humans are presented, all at eye- and skin-safe optical exposure levels. The progression of LUS imaging from tissue-mimicking phantoms, to excised animal tissue, to humans in vivo is shown, with validation from conventional ultrasound images. The LUS system design insights and results presented here inspire further LUS development and are a significant step toward the clinical implementation of LUS.
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Affiliation(s)
- Xiang Zhang
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139 USA
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, 45 Carleton St., Cambridge, MA 02142 USA
| | - Jonathan R. Fincke
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139 USA
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, 45 Carleton St., Cambridge, MA 02142 USA
| | - Charles M. Wynn
- Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, MA 02421 USA
| | - Matt R. Johnson
- Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, MA 02421 USA
| | - Robert W. Haupt
- Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, MA 02421 USA
| | - Brian W. Anthony
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139 USA
- Institute for Medical Engineering & Science, Massachusetts Institute of Technology, 45 Carleton St., Cambridge, MA 02142 USA
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17
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Ma Z, Luo S, Yu M, Liu J, Zhao Y, Yu Y, Lv J, Zhang X, Wang Y. Assessment of microvasculature flow state with a high speed all-optic dual-modal system of optical coherence tomography and photoacoustic imaging. BIOMEDICAL OPTICS EXPRESS 2018; 9:6103-6115. [PMID: 31065416 PMCID: PMC6490985 DOI: 10.1364/boe.9.006103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 10/12/2018] [Accepted: 11/04/2018] [Indexed: 05/13/2023]
Abstract
We propose a high speed all-optic dual-modal system that combines spectral domain optical coherence tomography (SDOCT) and photoacoustic imaging (PAI) to evaluate microvasculature flow states. A homodyne interferometer was used to remotely detect the surface vibration caused by photoacoustic (PA) waves. The PA excitation, PA probing and SDOCT probing beams share the same X-Y galvanometer scanner to perform fast two-dimensional scanning. In addition, we introduced multi-excitation, dual-channel acquisition and sensitivity compensation to improve the imaging speed of the PAI sub-system. The total time for imaging a sample with 256 × 256 pixels is less than 1 minute. The performance of the proposed system was verified by in vivo imaging of the vascular system in a mouse pinna with normal and then blocked blood circulations. The experimental results indicate that the proposed system is capable of revealing different blood flow states (static and moving) and is useful for the study of diseases related to functional blood supply.
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Affiliation(s)
- Zhenhe Ma
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Shuzhuo Luo
- School of Computer Science and Engineering, Northeastern University, Shenyang 110004, China
| | - Menghan Yu
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Jian Liu
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Yuqian Zhao
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Yao Yu
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Jiangtao Lv
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
| | - Xiaofang Zhang
- School of Optoelectronics, Beijing Institute of Technology, Beijing 100081, China
| | - Yi Wang
- School of Control Engineering, Northeastern University at Qinhuangdao, Qinhuangdao 066004, China
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18
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Fincke JR, Wynn CM, Haupt R, Zhang X, Rivera D, Anthony B. Characterization of laser ultrasound source signals in biological tissues for imaging applications. JOURNAL OF BIOMEDICAL OPTICS 2018; 24:1-11. [PMID: 30550046 PMCID: PMC6987635 DOI: 10.1117/1.jbo.24.2.021206] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 11/07/2018] [Indexed: 05/30/2023]
Abstract
Short optical pulses emitted from a tunable Q-switched laser (800 to 2000 nm) generate laser ultrasound (LUS) signals at the surface of biological tissue. The LUS signal's acoustic frequency content, dependence on sample type, and optical wavelength are observed in the far field. The experiments yield a reference dataset for the design of noncontact LUS imaging systems. Measurements show that the majority of LUS signal energy in biological tissues is within the 0.5 and 3 MHz frequency bands and the total acoustic energy generated increases with the optical absorption coefficient of water, which governs tissue optical absorption in the infrared range. The experimental results also link tissue surface roughness and acoustic attenuation with limited LUS signal bandwidth in biological tissue. Images constructed using 810-, 1064-, 1550-, and 2000-nm generation laser wavelengths and a contact piezoelectric receiver demonstrates the impact of the generation laser wavelength on image quality. A noncontact LUS-based medical imaging system has the potential to be an effective medical imaging device. Such a system may mitigate interoperator variability associated with current medical ultrasound imaging techniques and expand the scope of imaging applications for ultrasound.
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Affiliation(s)
- Jonathan R. Fincke
- Massachusetts Institute of Technology, Department of Mechanical Engineering, Cambridge, Massachusetts, United States
- Institute for Medical Engineering and Science (IMES), Massachusetts Institute of Technology, Cambridge, Massachusetts, United States
| | - Charles M. Wynn
- Massachusetts Institute of Technology, Lincoln Laboratory, Lexington, Massachusetts, United States
| | - Rob Haupt
- Massachusetts Institute of Technology, Lincoln Laboratory, Lexington, Massachusetts, United States
| | - Xiang Zhang
- Massachusetts Institute of Technology, Department of Mechanical Engineering, Cambridge, Massachusetts, United States
- Institute for Medical Engineering and Science (IMES), Massachusetts Institute of Technology, Cambridge, Massachusetts, United States
| | - Diego Rivera
- Massachusetts Institute of Technology, Lincoln Laboratory, Lexington, Massachusetts, United States
| | - Brian Anthony
- Massachusetts Institute of Technology, Department of Mechanical Engineering, Cambridge, Massachusetts, United States
- Institute for Medical Engineering and Science (IMES), Massachusetts Institute of Technology, Cambridge, Massachusetts, United States
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19
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The Progress in Photoacoustic and Laser Ultrasonic Tomographic Imaging for Biomedicine and Industry: A Review. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8101931] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The current paper reviews a set of principles and applications of photoacoustic and laser ultrasonic imaging, developed in the Laser Optoacoustic Laboratories of ILIT RAS, NUST MISiS, and ILC MSU. These applications include combined photoacoustic and laser ultrasonic imaging for biological objects, and tomographic laser ultrasonic imaging of solids. Principles, algorithms, resolution of the developed methods, and related problems are discussed. The review is written in context of the current state-of-art of photoacoustic and laser ultrasonic imaging.
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20
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Bell KL, Hajireza P, Zemp RJ. Coherence-gated photoacoustic remote sensing microscopy. OPTICS EXPRESS 2018; 26:23689-23704. [PMID: 30184866 DOI: 10.1364/oe.26.023689] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Photoacoustic remote sensing microscopy (PARS) represents a new paradigm within the optical imaging community by providing high sensitivity (>50 dB in vivo) non-contact optical absorption contrast in scattering media with a reflection-mode configuration. Unlike contact-based photoacoustic modalities which can acquire complete A-scans with a single excitation pulse due to slow acoustic propagation facilitating the use of time-gated collection of returning acoustic signals, PARS provides depth resolution only through optical sectioning. Here we introduce a new approach for providing coherence-gated depth-resolved PARS imaging using a difference between pulsed-interrogation optical coherence tomography scan-lines with and without excitation pulses. Proposed methods are validated using simulations which account for pulsed-laser induced initial-pressures and accompanying refractive index changes. The changes in refractive index are shown to be proportional to optical absorption. It is demonstrated that to achieve optimal image quality, several key parameters must be selected including interrogation pulse duration and delay. The proposed approach offers the promise of non-contact depth-resolved optical absorption contrast at optical-resolution scales and may complement the scattering contrast offered by optical coherence tomography.
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21
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Wissmeyer G, Pleitez MA, Rosenthal A, Ntziachristos V. Looking at sound: optoacoustics with all-optical ultrasound detection. LIGHT, SCIENCE & APPLICATIONS 2018; 7:53. [PMID: 30839640 PMCID: PMC6107019 DOI: 10.1038/s41377-018-0036-7] [Citation(s) in RCA: 121] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 05/08/2018] [Accepted: 05/11/2018] [Indexed: 05/03/2023]
Abstract
Originally developed for diagnostic ultrasound imaging, piezoelectric transducers are the most widespread technology employed in optoacoustic (photoacoustic) signal detection. However, the detection requirements of optoacoustic sensing and imaging differ from those of conventional ultrasonography and lead to specifications not sufficiently addressed by piezoelectric detectors. Consequently, interest has shifted to utilizing entirely optical methods for measuring optoacoustic waves. All-optical sound detectors yield a higher signal-to-noise ratio per unit area than piezoelectric detectors and feature wide detection bandwidths that may be more appropriate for optoacoustic applications, enabling several biomedical or industrial applications. Additionally, optical sensing of sound is less sensitive to electromagnetic noise, making it appropriate for a greater spectrum of environments. In this review, we categorize different methods of optical ultrasound detection and discuss key technology trends geared towards the development of all-optical optoacoustic systems. We also review application areas that are enabled by all-optical sound detectors, including interventional imaging, non-contact measurements, magnetoacoustics, and non-destructive testing.
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Affiliation(s)
- Georg Wissmeyer
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging, Technische Universität München, Munich, Germany
| | - Miguel A. Pleitez
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging, Technische Universität München, Munich, Germany
| | - Amir Rosenthal
- Andrew and Erna Viterbi Faculty of Electrical Engineering, Technion - Israel Institute of Technology, Haifa, Israel
| | - Vasilis Ntziachristos
- Institute of Biological and Medical Imaging, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Biological Imaging, Technische Universität München, Munich, Germany
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22
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Smirni S, MacDonald MP, Robertson CP, McNamara PM, O'Gorman S, Leahy MJ, Khan F. Application of cmOCT and continuous wavelet transform analysis to the assessment of skin microcirculation dynamics. JOURNAL OF BIOMEDICAL OPTICS 2018; 23:1-13. [PMID: 29992798 DOI: 10.1117/1.jbo.23.7.076006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 06/15/2018] [Indexed: 06/08/2023]
Abstract
Correlation mapping optical coherence tomography (cmOCT) is a powerful technique for the imaging of skin microvessels structure, based on the discrimination of the static and dynamic regions of the tissue. Although the suitability of cmOCT to visualize the microcirculation has been proved in humans and animal models, less evidence has been provided about its application to examine functional dynamics. Therefore, the goal of this research was validating the cmOCT method for the investigation into microvascular function and vasomotion. A spectral domain optical coherence tomography (SD-OCT) device was employed to image 90 sequential three-dimensional (3-D) OCT volumes from the forearm of 12 volunteers during a 25-min postocclusive reactive hyperemia (PORH) test. The volumes were processed using cmOCT to generate blood flow maps at selected cutaneous depths. The maps clearly trace flow variations during the PORH response for both capillaries and arterioles/venules microvascular layers. Continuous blood flow signals were reconstructed from cmOCT maps to study vasomotion by applying wavelet transform spectral analysis, which revealed fluctuations of flow during PORH, reflecting the regulation of microvascular tone mediated by endothelial cells and sympathetic nerves. The results clearly demonstrate that cmOCT allows the generation of functional information that may be used for diagnostic applications.
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Affiliation(s)
- Salvatore Smirni
- University of Dundee, School of Medicine, Ninewells Hospital, Dundee, United Kingdom
| | - Michael P MacDonald
- University of Dundee, School of Medicine, Ninewells Hospital, Dundee, United Kingdom
- University of Dundee, School of Science and Engineering, Nethergate, Dundee, United Kingdom
| | - Catherine P Robertson
- University of Dundee, School of Medicine, Ninewells Hospital, Dundee, United Kingdom
| | - Paul M McNamara
- National University of Ireland, Tissue Optics and Microcirculation Imaging Facility, Galway, Ireland
| | - Sean O'Gorman
- National University of Ireland, Tissue Optics and Microcirculation Imaging Facility, Galway, Ireland
| | - Martin J Leahy
- National University of Ireland, Tissue Optics and Microcirculation Imaging Facility, Galway, Ireland
- Royal College of Surgeons (RCSI), Dublin, Ireland
| | - Faisel Khan
- University of Dundee, School of Medicine, Ninewells Hospital, Dundee, United Kingdom
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23
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Pan W, Peng W, Ning F, Zhang Y, Zhang Y, Wang Y, Xie W, Zhang J, Xin H, Li C, Zhang X. Non-invasive detection of the early phase of kidney injury by photoacoustic/computed tomography imaging. NANOTECHNOLOGY 2018; 29:265101. [PMID: 29718825 DOI: 10.1088/1361-6528/aabcee] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The early diagnosis of kidney diseases, which can remarkably impair the quality of life and are costly, has encountered great difficulties. Therefore, the development of methods for early diagnosis has great clinical significance. In this study, we used an emerging technique of photoacoustic (PA) imaging, which has relatively high spatial resolution and good imaging depth. Two kinds of PA gold nanoparticle (GNP)-based bioprobes were developed based on their superior photo detectability, size controllability and biocompatibility. The kidney injury mouse model was developed by unilateral ureteral obstruction for 96 h and the release of obstruction model). Giving 3.5 and 5.5 nm bioprobes by tail vein injection, we found that the 5.5 nm probe could be detected in the bladder in the model group, but not in the control group. These results were confirmed by computed tomography imaging. Furthermore, the model group did not show changes in the blood biochemical indices (BUN and Scr) and histologic examination. The 5.5 nm GNPs were found to be the critical point for early diagnosis of kidney injury. This new method was faster and more sensitive and accurate for the detection of renal injury, compared with conventional methods, and can be used for the development of a PA GNP-based bioprobe for diagnosing renal injury.
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Affiliation(s)
- Wanma Pan
- Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai 201203, People's Republic of China
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24
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George D, Lloyd H, Silverman RH, Chitnis PV. A frequency-domain non-contact photoacoustic microscope based on an adaptive interferometer. JOURNAL OF BIOPHOTONICS 2018; 11:e201700278. [PMID: 29314709 PMCID: PMC6746176 DOI: 10.1002/jbio.201700278] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 01/04/2018] [Indexed: 05/05/2023]
Abstract
A frequency-domain, non-contact approach to photoacoustic microscopy (PAM) that employs amplitude-modulated (0.1-1 MHz) laser for excitation (638-nm pump) in conjunction with a 2-wave mixing interferometer (532-nm probe) for non-contact detection of photoacoustic waves at the specimen surface is presented. A lock-in amplifier is employed to detect the photoacoustic signal. Illustrative images of tissue-mimicking phantoms, red-blood cells and retinal vasculature are presented. Single-frequency modulation of the pump beam directly provides an image that is equivalent to the 2-dimensional projection of the image volume. Targets located superficially produce phase modulations in the surface-reflected probe beam due to surface vibrations as well as direct intensity modulation in the backscattered probe light due to local changes in pressure and/or temperature. In comparison, the observed modulations in the probe beam due to targets located deeper in the specimen, for example, beyond the ballistic photon regime, predominantly consist of phase modulation.
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Affiliation(s)
- Deepu George
- Department of Bioengineering, George Mason University, Fairfax, Virginia
| | - Harriet Lloyd
- Edward S Harkness Eye Institute, Columbia University Medical Center, New York, New York
| | - Ronald H. Silverman
- Edward S Harkness Eye Institute, Columbia University Medical Center, New York, New York
| | - Parag V. Chitnis
- Department of Bioengineering, George Mason University, Fairfax, Virginia
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25
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Demirkiran A, Karakuzu A, Erkol H, Torun H, Unlu MB. Analysis of microcantilevers excited by pulsed-laser-induced photoacoustic waves. OPTICS EXPRESS 2018; 26:4906-4919. [PMID: 29475334 DOI: 10.1364/oe.26.004906] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 01/04/2018] [Indexed: 06/08/2023]
Abstract
This study presents a simulation-based analysis on the excitation of microcantilever in air using pulsed-laser-induced photoacoustic waves. A model was designed and coded to investigate the effects of consecutive photoacoustic waves, arising from a spherical light absorber illuminated by short laser pulses. The consecutiveness of the waves were adjusted with respect to the pulse repetition frequency of the laser to examine their cumulative effects on the oscillation of microcantilever. Using this approach, oscillation characteristics of two rectangular cantilevers with different resonant frequencies (16.9 kHz and 505.7 kHz) were investigated in the presence of the random oscillations. The results show that the effective responses of the microcantilevers to the consecutive photoacoustic waves provide steady-state oscillations, when the pulse repetition frequency matches to the fundamental resonant frequency or its lower harmonics. Another major finding is that being driven by the same photoacoustic pressure value, the high frequency cantilever tend to oscillate at higher amplitudes. Some of the issues emerging from these findings may find application area in atomic force microscopy actuation and photoacoustic signal detection.
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26
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Bell KL, Hajireza P, Shi W, Zemp RJ. Temporal evolution of low-coherence reflectrometry signals in photoacoustic remote sensing microscopy. APPLIED OPTICS 2017; 56:5172-5181. [PMID: 29047569 DOI: 10.1364/ao.56.005172] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 05/22/2017] [Indexed: 05/22/2023]
Abstract
Recently, a new noncontact reflection-mode imaging modality called photoacoustic remote sensing (PARS) microscopy was introduced providing optical absorption contrast. Unlike previous modalities, which rely on interferometric detection of a probe beam to measure surface oscillations, the PARS technique detects photoacoustic initial pressures induced by a pulsed laser at their origin by monitoring intensity modulations of a reflected probe beam. In this paper, a model describing the temporal evolution from a finite excitation pulse is developed with consideration given to the coherence length of the interrogation beam. Analytical models are compared with approximations, finite-difference time-domain (FDTD) simulations, and experiments with good agreement.
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27
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Hajireza P, Shi W, Bell K, Paproski RJ, Zemp RJ. Non-interferometric photoacoustic remote sensing microscopy. LIGHT, SCIENCE & APPLICATIONS 2017; 6:e16278. [PMID: 30167263 PMCID: PMC6062239 DOI: 10.1038/lsa.2016.278] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 12/21/2016] [Accepted: 01/04/2017] [Indexed: 05/05/2023]
Abstract
Elasto-optical refractive index modulation due to photoacoustic initial pressure transients produced significant reflection of a probe beam when the absorbing interface had an appreciable refractive index difference. This effect was harnessed in a new form of non-contact optical resolution photoacoustic microscopy called photoacoustic remote sensing microscopy. A non-interferometric system architecture with a low-coherence probe beam precludes detection of surface oscillations and other phase-modulation phenomenon. The probe beam was confocal with a scanned excitation beam to ensure detection of initial pressure-induced intensity reflections at the subsurface origin where pressures are largest. Phantom studies confirmed signal dependence on optical absorption, index contrast and excitation fluence. In vivo imaging of superficial microvasculature and melanoma tumors was demonstrated with ~2.7±0.5 μm lateral resolution.
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Affiliation(s)
- Parsin Hajireza
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta, T6G 2V4 Canada
- IllumiSonics, Inc., 5205-38A Ave. N.W., Edmonton, Alberta, T6L 2J4, Canada
| | - Wei Shi
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta, T6G 2V4 Canada
| | - Kevan Bell
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta, T6G 2V4 Canada
| | - Robert J Paproski
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta, T6G 2V4 Canada
| | - Roger J Zemp
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta, T6G 2V4 Canada
- IllumiSonics, Inc., 5205-38A Ave. N.W., Edmonton, Alberta, T6L 2J4, Canada
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28
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Johnson JL, Shragge J, van Wijk K. Nonconfocal all-optical laser-ultrasound and photoacoustic imaging system for angle-dependent deep tissue imaging. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:41014. [PMID: 28125155 DOI: 10.1117/1.jbo.22.4.041014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 01/03/2017] [Indexed: 05/28/2023]
Abstract
Biomedical imaging systems incorporating both photoacoustic (PA) and ultrasound capabilities are of interest for obtaining optical and acoustic properties deep in tissue. While most dual-modality systems utilize piezoelectric transducers, all-optical systems can obtain broadband high-resolution data with hands-free operation. Previously described reflection-mode all-optical laser-ultrasound (LUS) systems use a confocal source and detector; however, angle-dependent raypaths are lost in this configuration. As a result, the overall imaging aperture is reduced, which becomes increasingly problematic with depth. We present a reflection-mode nonconfocal LUS and PA imaging system that uses signals recorded on all-optical hardware to create angle-dependent images. We use reverse-time migration and time reversal to reconstruct the LUS and PA images. We demonstrate this methodology with both a numerical model and tissue phantom experiment to image a steep-curvature vessel with a limited aperture 2-cm beneath the surface. Nonconfocal imaging demonstrates improved focusing by 30% and 15% compared to images acquired with a single LUS source in the numerical and experimental LUS images, respectively. The appearance of artifacts is also reduced. Complementary PA images are straightforward to acquire with the nonconfocal system by tuning the source wavelength and can be further developed for quantitative multiview PA imaging.
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Affiliation(s)
- Jami L Johnson
- University of Auckland, Faculty of Science, The Dodd-Walls Centre for Photonic and Quantum Technologies and Department of Physics, Private Bag 92019, Auckland 1010, New Zealand
| | - Jeffrey Shragge
- The University of Western Australia, Faculty of Science, School of Physics and School of Earth Sciences, M004 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Kasper van Wijk
- University of Auckland, Faculty of Science, The Dodd-Walls Centre for Photonic and Quantum Technologies and Department of Physics, Private Bag 92019, Auckland 1010, New Zealand
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29
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Kim KH, Luo W, Zhang C, Tian C, Guo LJ, Wang X, Fan X. Air-coupled ultrasound detection using capillary-based optical ring resonators. Sci Rep 2017; 7:109. [PMID: 28250443 PMCID: PMC5427941 DOI: 10.1038/s41598-017-00134-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 02/09/2017] [Indexed: 11/20/2022] Open
Abstract
We experimentally demonstrate and theoretically analyze high Q-factor (~107) capillary-based optical ring resonators for non-contact detection of air-coupled ultrasound. Noise equivalent pressures in air as low as 215 mPa/√Hz and 41 mPa/√Hz at 50 kHz and 800 kHz in air, respectively, are achieved. Furthermore, non-contact detection of air-coupled photoacoustic pulses optically generated from a 200 nm thick Chromium film is demonstrated. The interaction of an acoustic pulse and the mechanical mode of the ring resonator is also studied. Significant improvement in detection bandwidth is demonstrated by encapsulating the ring resonator in a damping medium. Our work will enable compact and sensitive ultrasound detection in many applications, such as air-coupled non-destructive ultrasound testing, photoacoustic imaging, and remote sensing. It will also provide a model system for fundamental study of the mechanical modes in the ring resonator.
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Affiliation(s)
- Kyu Hyun Kim
- Department of Biomedical Engineering, University of Michigan, 1101 Beal Ave., Ann Arbor, MI, 48109, USA
- Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Ave., Ann Arbor, MI, 48109, USA
| | - Wei Luo
- Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Ave., Ann Arbor, MI, 48109, USA
- School of Optical and Electrical Information, Huazhong University of Science and Technology, 1037 Luoyu Road, Hongshan District, 430074, Wuhan, Hubei, PR China
| | - Cheng Zhang
- Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Ave., Ann Arbor, MI, 48109, USA
| | - Chao Tian
- Department of Biomedical Engineering, University of Michigan, 1101 Beal Ave., Ann Arbor, MI, 48109, USA
| | - L Jay Guo
- Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Ave., Ann Arbor, MI, 48109, USA
| | - Xueding Wang
- Department of Biomedical Engineering, University of Michigan, 1101 Beal Ave., Ann Arbor, MI, 48109, USA
| | - Xudong Fan
- Department of Biomedical Engineering, University of Michigan, 1101 Beal Ave., Ann Arbor, MI, 48109, USA.
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Liang Y, Jin L, Wang L, Bai X, Cheng L, Guan BO. Fiber-Laser-Based Ultrasound Sensor for Photoacoustic Imaging. Sci Rep 2017; 7:40849. [PMID: 28098201 PMCID: PMC5241646 DOI: 10.1038/srep40849] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 12/12/2016] [Indexed: 01/15/2023] Open
Abstract
Photoacoustic imaging, especially for intravascular and endoscopic applications, requires ultrasound probes with miniature size and high sensitivity. In this paper, we present a new photoacoustic sensor based on a small-sized fiber laser. Incident ultrasound waves exert pressures on the optical fiber laser and induce harmonic vibrations of the fiber, which is detected by the frequency shift of the beating signal between the two orthogonal polarization modes in the fiber laser. This ultrasound sensor presents a noise-equivalent pressure of 40 Pa over a 50-MHz bandwidth. We demonstrate this new ultrasound sensor on an optical-resolution photoacoustic microscope. The axial and lateral resolutions are 48 μm and 3.3 μm. The field of view is up to 1.57 mm2. The sensor exhibits strong resistance to environmental perturbations, such as temperature changes, due to common-mode cancellation between the two orthogonal modes. The present fiber laser ultrasound sensor offers a new tool for all-optical photoacoustic imaging.
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Affiliation(s)
- Yizhi Liang
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon, Hong Kong SAR, China
| | - Long Jin
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China
| | - Lidai Wang
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Ave, Kowloon, Hong Kong SAR, China
| | - Xue Bai
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China
| | - Linghao Cheng
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China
| | - Bai-Ou Guan
- Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Institute of Photonics Technology, Jinan University, Guangzhou 510632, China
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Thrall JH. Trends and Developments Shaping the Future of Diagnostic Medical Imaging: 2015 Annual Oration in Diagnostic Radiology. Radiology 2016; 279:660-6. [PMID: 27183401 DOI: 10.1148/radiol.2016160293] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- James H Thrall
- From the Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 25 New Chardon St, Suite 400, Boston, MA 02114
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Tian C, Feng T, Wang C, Liu S, Cheng Q, Oliver DE, Wang X, Xu G. Non-Contact Photoacoustic Imaging Using a Commercial Heterodyne Interferometer. IEEE SENSORS JOURNAL 2016; 16:8381-8388. [PMID: 28210188 PMCID: PMC5305171 DOI: 10.1109/jsen.2016.2611569] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Most current photoacoustic imaging (PAI) systems employ piezoelectric transducers to receive photoacoustic signals, which requires coupling medium to facilitate photoacoustic wave propagation and are not favored in many applications. Here, we report an all-optical non-contact PAI system based on a commercial heterodyne interferometer working at 1550 nm. The interferometer remotely detects ultrasound-induced surface vibration and does not involve any physical contact with the sample. The theoretically predicated and experimentally measured noise equivalent detection limits of the optical sensor are about 4.5 and 810 Pa over 1.2 MHz bandwidth. Using a raster-scan PAI system equipped with the non-contact design, stereotactic boundaries of an artificial tumor in a pig brain were accurately delineated. The non-contact design also enables the tomographic PAI of biological tissue samples in a non-invasive manner. The preliminary results and analyses reveal that the heterodyne interferometer-based non-contact PAI system holds good potential in biomedical imaging.
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Affiliation(s)
- Chao Tian
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109 USA
| | - Ting Feng
- Department of Electronic Science and Engineering, Nanjing University, Nanjing 21000, China, and also with the Department of Radiology, University of Michigan, Ann Arbor, MI 48109 USA
| | - Cheng Wang
- School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Shengchun Liu
- College of Physical Science and Technology, Heilongjiang University, Harbin 150080, China
| | - Qian Cheng
- Institute of Acoustics, Tongji University, Shanghai 200092, China
| | | | - Xueding Wang
- Department of Biomedical Engineering and the Department of Radiology, University of Michigan, Ann Arbor, MI 48109 USA, and also with the Institute of Acoustics, Tongji University, Shanghai 200092, China
| | - Guan Xu
- Department of Radiology, University of Michigan, Ann Arbor, MI 48109 USA
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In Vivo Near Infrared Virtual Intraoperative Surgical Photoacoustic Optical Coherence Tomography. Sci Rep 2016; 6:35176. [PMID: 27731390 PMCID: PMC5059626 DOI: 10.1038/srep35176] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 09/26/2016] [Indexed: 01/06/2023] Open
Abstract
Since its first implementation in otolaryngological surgery nearly a century ago, the surgical microscope has improved the accuracy and the safety of microsurgeries. However, the microscope shows only a magnified surface view of the surgical region. To overcome this limitation, either optical coherence tomography (OCT) or photoacoustic microscopy (PAM) has been independently combined with conventional surgical microscope. Herein, we present a near-infrared virtual intraoperative photoacoustic optical coherence tomography (NIR-VISPAOCT) system that combines both PAM and OCT with a conventional surgical microscope. Using optical scattering and absorption, the NIR-VISPAOCT system simultaneously provides surgeons with real-time comprehensive biological information such as tumor margins, tissue structure, and a magnified view of the region of interest. Moreover, by utilizing a miniaturized beam projector, it can back-project 2D cross-sectional PAM and OCT images onto the microscopic view plane. In this way, both microscopic and cross-sectional PAM and OCT images are concurrently displayed on the ocular lens of the microscope. To verify the usability of the NIR-VISPAOCT system, we demonstrate simulated surgeries, including in vivo image-guided melanoma resection surgery and in vivo needle injection of carbon particles into a mouse thigh. The proposed NIR-VISPAOCT system has potential applications in neurosurgery, ophthalmological surgery, and other microsurgeries.
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Liu W, Zhang HF. Photoacoustic imaging of the eye: A mini review. PHOTOACOUSTICS 2016; 4:112-123. [PMID: 27761410 PMCID: PMC5063360 DOI: 10.1016/j.pacs.2016.05.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 04/15/2016] [Accepted: 05/17/2016] [Indexed: 05/04/2023]
Abstract
The eye relies on the synergistic cooperation of many different ocular components, including the cornea, crystalline lens, photoreceptors, and retinal neurons, to precisely sense visual information. Complications with a single ocular component can degrade vision and sometimes cause blindness. Immediate treatment and long-term monitoring are paramount to alleviate symptoms, restore vision, and cure ocular diseases. However, successful treatment requires understanding ocular pathological mechanisms, precisely detecting and monitoring the diseases. The investigation and diagnosis of ocular diseases require advanced medical tools. In this mini review, we discuss non-invasive photoacoustic (PA) imaging as a potential research tool and medical screening device. In the research setting, PA imaging can provide valuable information on the disease progression. In the clinical setting, PA imaging can potentially aid in disease detection and treatment monitoring.
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Affiliation(s)
- Wenzhong Liu
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208,USA
| | - Hao F. Zhang
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208,USA
- Department of Ophthalmology, Northwestern University, Chicago, IL 60611, USA
- Corresponding author at: Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA.
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Leiss-Holzinger E, Bauer-Marschallinger J, Hochreiner A, Hollinger P, Berer T. Dual Modality Noncontact Photoacoustic and Spectral Domain OCT Imaging. ULTRASONIC IMAGING 2016; 38:19-31. [PMID: 25900968 PMCID: PMC4702283 DOI: 10.1177/0161734615582003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We developed a multimodal imaging system, combining noncontact photoacoustic imaging and optical coherence tomography (OCT). Photoacoustic signals are recorded without contact to the specimens' surface by using an interferometric technique. The interferometer is realized within a fiber-optic network using a fiber laser at 1550 nm as source. The fiber-optic network allows the integration of a fiber-based OCT system operating at a wavelength region around 1310 nm. Light from the fiber laser and the OCT source are multiplexed into one fiber using wavelength-division multiplexing. The same focusing optics is used for both modalities. Back-reflected light from the sample is demultiplexed and guided to the respective imaging systems. As the same optical components are used for OCT and photoacoustic imaging, the obtained images are co-registered intrinsically in lateral direction. Three-dimensional imaging is implemented by hybrid galvanometer and mechanical scanning. To allow fast B-scan measurements, scanning of the interrogation beam along one dimension is executed by a galvanometer scanner. Slow-axis scanning, perpendicular to the fast axis, is performed utilizing a linear translational stage. We demonstrate two-dimensional and three-dimensional imaging on agarose phantoms.
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Affiliation(s)
| | | | - Armin Hochreiner
- Research Center for Non-Destructive Testing GmbH (RECENDT), Linz, Austria
| | - Philipp Hollinger
- Research Center for Non-Destructive Testing GmbH (RECENDT), Linz, Austria
| | - Thomas Berer
- Research Center for Non-Destructive Testing GmbH (RECENDT), Linz, Austria
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Chen SL, Guo LJ, Wang X. All-optical photoacoustic microscopy. PHOTOACOUSTICS 2015; 3:143-150. [PMID: 31467845 PMCID: PMC6713062 DOI: 10.1016/j.pacs.2015.11.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 11/06/2015] [Accepted: 11/13/2015] [Indexed: 05/04/2023]
Abstract
Three-dimensional photoacoustic microscopy (PAM) has gained considerable attention within the biomedical imaging community during the past decade. Detecting laser-induced photoacoustic waves by optical sensing techniques facilitates the idea of all-optical PAM (AOPAM), which is of particular interest as it provides unique advantages for achieving high spatial resolution using miniaturized embodiments of the imaging system. The review presents the technology aspects of optical-sensing techniques for ultrasound detection, such as those based on optical resonators, as well as system developments of all-optical photoacoustic systems including PAM, photoacoustic endoscopy, and multi-modality microscopy. The progress of different AOPAM systems and their representative applications are summarized.
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Affiliation(s)
- Sung-Liang Chen
- University of Michigan-Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai, 200240, China
| | - L. Jay Guo
- Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan, 48109, USA
| | - Xueding Wang
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, 48109, USA
- Corresponding author at: Tel.: +1734-647-2728; fax: +1734-764-8541.
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37
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Eom J, Park SJ, Lee BH. Noncontact photoacoustic tomography of in vivo chicken chorioallantoic membrane based on all-fiber heterodyne interferometry. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:106007. [PMID: 26473590 DOI: 10.1117/1.jbo.20.10.106007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 09/22/2015] [Indexed: 05/26/2023]
Abstract
We present three-dimensional (3-D) in vivo photoacoustic (PA) images of the blood vasculature of a chicken chorioallantoic membrane (CAM) obtained by using a fiber-based noncontact PA tomography system. With a fiber-optic heterodyne interferometer, the system measures the surface displacement of a sample, induced by the PA wave, which overcomes the disadvantage of physical-contact of ultrasonic transducer in a conventional system. The performance of an implemented system is analyzed and its capability of in vivo 3-D bioimaging is presented. At a depth of 2.5 mm in a phantom experiment, the lateral and axial resolutions were measured as 100 and 30 μm, respectively. The lateral resolution became doubled at a depth of 7.0 mm; however, interestingly, the axial resolution was not noticeably deteriorated with the depth. With the CAM experiment, performed under the American National Standards Institute laser safety standard condition, blood vessel structures placed as deep as 3.5 mm were clearly recognized.
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Affiliation(s)
- Jonghyun Eom
- Gwangju Institute of Science and Technology, Department of Medical System Engineering, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712, Republic of Korea
| | - Seong Jun Park
- Institute for Basic Science, Center for Soft and Living Matter, 50 UNIST-gil, Ulju-gun, Ulsan 689-798, Republic of Korea
| | - Byeong Ha Lee
- Gwangju Institute of Science and Technology, School of Information and Communications, 123 Cheomdan-gwagiro, Buk-gu, Gwangju 500-712, Republic of Korea
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38
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Chen Z, Yang S, Wang Y, Xing D. All-optically integrated photo-acoustic microscopy and optical coherence tomography based on a single Michelson detector. OPTICS LETTERS 2015; 40:2838-41. [PMID: 26076275 DOI: 10.1364/ol.40.002838] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
An all-optically noncontact dual-mode imaging system using a single Michelson detector that simultaneously achieved photo-acoustic microscopy (PAM) and optical coherence tomography (OCT) is presented. The pulse laser-induced photo-acoustic signals and the back-scattered photons were alternately detected by a single Michelson detector. The spatial resolution and imaging capability of the dual-mode imaging system were testified by scattering phantoms. Furthermore, in vivo images of the mouse ear demonstrated that the PAM-OCT can provide complementary anatomical and functional information for imaging of biological tissues, which could be the best co-imaging strategy of PAM and OCT in biomedicine.
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39
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Horstmann J, Spahr H, Buj C, Münter M, Brinkmann R. Full-field speckle interferometry for non-contact photoacoustic tomography. Phys Med Biol 2015; 60:4045-58. [PMID: 25927910 DOI: 10.1088/0031-9155/60/10/4045] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A full-field speckle interferometry method for non-contact and prospectively high speed Photoacoustic Tomography is introduced and evaluated as proof of concept. Thermoelastic pressure induced changes of the objects topography are acquired in a repetitive mode without any physical contact to the object. In order to obtain high acquisition speed, the object surface is illuminated by laser pulses and imaged onto a high speed camera chip. In a repetitive triple pulse mode, surface displacements can be acquired with nanometre sensitivity and an adjustable sampling rate of e.g. 20 MHz with a total acquisition time far below one second using kHz repetition rate lasers. Due to recurring interferometric referencing, the method is insensitive to thermal drift of the object due to previous pulses or other motion. The size of the investigated area and the spatial and temporal resolution of the detection are scalable. In this study, the approach is validated by measuring a silicone phantom and a porcine skin phantom with embedded silicone absorbers. The reconstruction of the absorbers is presented in 2D and 3D. The sensitivity of the measurement with respect to the photoacoustic detection is discussed. Potentially, Photoacoustic Imaging can be brought a step closer towards non-anaesthetized in vivo imaging and new medical applications not allowing acoustic contact, such as neurosurgical monitoring or burnt skin investigation.
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Affiliation(s)
- Jens Horstmann
- Medical Laser Center Lübeck GmbH, Peter-Monnik-Weg 4, 23562 Lübeck, Germany
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40
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Berer T, Leiss-Holzinger E, Hochreiner A, Bauer-Marschallinger J, Buchsbaum A. Multimodal noncontact photoacoustic and optical coherence tomography imaging using wavelength-division multiplexing. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:46013. [PMID: 25919425 DOI: 10.1117/1.jbo.20.4.046013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 04/03/2015] [Indexed: 05/09/2023]
Abstract
We present multimodal noncontact photoacoustic (PA) and optical coherence tomography (OCT) imaging. PA signals are acquired remotely on the surface of a specimen with a Mach-Zehnder interferometer. The interferometer is realized in a fiber-optic network using a fiber laser at 1550 nm as the source. In the same fiber-optic network, a spectral-domain OCT system is implemented. The OCT system utilizes a supercontinuum light source at 1310 nm and a spectrometer with an InGaAs line array detector. Light from the fiber laser and the OCT source is multiplexed into one fiber using a wavelength-division multiplexer; the same objective is used for both imaging modalities. Reflected light is spectrally demultiplexed and guided to the respective imaging systems. We demonstrate two-dimensional and three-dimensional imaging on a tissue-mimicking sample and a chicken skin phantom. The same fiber network and same optical components are used for PA and OCT imaging, and the obtained images are intrinsically coregistered.
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41
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Park SJ, Eom J, Kim YH, Lee CS, Lee BH. Noncontact photoacoustic imaging based on all-fiber heterodyne interferometer. OPTICS LETTERS 2014; 39:4903-6. [PMID: 25121904 DOI: 10.1364/ol.39.004903] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We report on a noncontact photoacoustic imaging system utilizing an all-fiber-optic heterodyne interferometer as an acoustic wave detector. The acoustic wave generated by a short laser pulse via the photoacoustic effect and arriving at the sample surface could be detected with the fiber-optic heterodyne interferometer without physical contact or using an impedance matching medium. A phantom experiment was conducted to evaluate the proposed system, and the initial acoustic pressure distribution was calculated using a Fourier-based reconstruction algorithm. It is expected that the all-fiber-optic configuration of the proposed system can be applied as a minimally invasive diagnostic tool.
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42
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Nuster R, Slezak P, Paltauf G. High resolution three-dimensional photoacoutic tomography with CCD-camera based ultrasound detection. BIOMEDICAL OPTICS EXPRESS 2014; 5:2635-47. [PMID: 25136491 PMCID: PMC4132994 DOI: 10.1364/boe.5.002635] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 07/10/2014] [Accepted: 07/12/2014] [Indexed: 05/07/2023]
Abstract
A photoacoustic tomograph based on optical ultrasound detection is demonstrated, which is capable of high resolution real-time projection imaging and fast three-dimensional (3D) imaging. Snapshots of the pressure field outside the imaged object are taken at defined delay times after photoacoustic excitation by use of a charge coupled device (CCD) camera in combination with an optical phase contrast method. From the obtained wave patterns photoacoustic projection images are reconstructed using a back propagation Fourier domain reconstruction algorithm. Applying the inverse Radon transform to a set of projections recorded over a half rotation of the sample provides 3D photoacoustic tomography images in less than one minute with a resolution below 100 µm. The sensitivity of the device was experimentally determined to be 5.1 kPa over a projection length of 1 mm. In vivo images of the vasculature of a mouse demonstrate the potential of the developed method for biomedical applications.
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Affiliation(s)
- Robert Nuster
- Department of Physics, Karl-Franzens-University Graz, 8010 Graz, Austria
| | - Paul Slezak
- Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria
| | - Guenther Paltauf
- Department of Physics, Karl-Franzens-University Graz, 8010 Graz, Austria
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43
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James J, Murukeshan VM, Woh LS. Integrated photoacoustic, ultrasound and fluorescence platform for diagnostic medical imaging-proof of concept study with a tissue mimicking phantom. BIOMEDICAL OPTICS EXPRESS 2014; 5:2135-44. [PMID: 25071954 PMCID: PMC4102354 DOI: 10.1364/boe.5.002135] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 04/29/2014] [Accepted: 05/07/2014] [Indexed: 05/03/2023]
Abstract
The structural and molecular heterogeneities of biological tissues demand the interrogation of the samples with multiple energy sources and provide visualization capabilities at varying spatial resolution and depth scales for obtaining complementary diagnostic information. A novel multi-modal imaging approach that uses optical and acoustic energies to perform photoacoustic, ultrasound and fluorescence imaging at multiple resolution scales from the tissue surface and depth is proposed in this paper. The system comprises of two distinct forms of hardware level integration so as to have an integrated imaging system under a single instrumentation set-up. The experimental studies show that the system is capable of mapping high resolution fluorescence signatures from the surface, optical absorption and acoustic heterogeneities along the depth (>2cm) of the tissue at multi-scale resolution (<1µm to <0.5mm).
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Affiliation(s)
- Joseph James
- The Centre for Optical and Lasers in Engineering (COLE), School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Vadakke Matham Murukeshan
- The Centre for Optical and Lasers in Engineering (COLE), School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Lye Sun Woh
- The Centre for Optical and Lasers in Engineering (COLE), School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
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44
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Gould T, Wang Q, Pfefer TJ. Optical-thermal light-tissue interactions during photoacoustic breast imaging. BIOMEDICAL OPTICS EXPRESS 2014; 5:832-47. [PMID: 24688817 PMCID: PMC3959836 DOI: 10.1364/boe.5.000832] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 01/26/2014] [Accepted: 01/29/2014] [Indexed: 05/04/2023]
Abstract
Light-tissue interactions during photoacoustic imaging, including dynamic heat transfer processes in and around vascular structures, are not well established. A three-dimensional, transient, optical-thermal computational model was used to simulate energy deposition, temperature distributions and thermal damage in breast tissue during exposure to pulsed laser trains at 800 and 1064 nm. Rapid and repetitive temperature increases and thermal relaxation led to superpositioning effects that were highly dependent on vessel diameter and depth. For a ten second exposure at established safety limits, the maximum single-pulse and total temperature rise levels were 0.2°C and 5.8°C, respectively. No significant thermal damage was predicted. The impact of tissue optical properties, surface boundary condition and irradiation wavelength on peak temperature location and temperature evolution with time are discussed.
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45
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Johnson JL, van Wijk K, Sabick M. Characterizing phantom arteries with multi-channel laser ultrasonics and photo-acoustics. ULTRASOUND IN MEDICINE & BIOLOGY 2014; 40:513-520. [PMID: 24412169 DOI: 10.1016/j.ultrasmedbio.2013.10.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Revised: 09/07/2013] [Accepted: 10/08/2013] [Indexed: 06/03/2023]
Abstract
Multi-channel photo-acoustic and laser ultrasonic waves are used to sense the characteristics of proxies for healthy and diseased vessels. The acquisition system is non-contacting and non-invasive with a pulsed laser source and a laser vibrometer detector. As the wave signatures of our targets are typically low in amplitude, we exploit multi-channel acquisition and processing techniques. These are commonly used in seismology to improve the signal-to-noise ratio of data. We identify vessel proxies with a diameter on the order of 1 mm, at a depth of 18 mm. Variations in scattered and photo-acoustic signatures are related to differences in vessel wall properties and content. The methods described have the potential to improve imaging and better inform interventions for atherosclerotic vessels, such as the carotid artery.
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Affiliation(s)
- Jami L Johnson
- Mechanical and Biomedical Engineering Department, Boise State University, Boise, Idaho, USA; Department of Physics, University of Auckland, Auckland, New Zealand.
| | - Kasper van Wijk
- Department of Physics, University of Auckland, Auckland, New Zealand
| | - Michelle Sabick
- Mechanical and Biomedical Engineering Department, Boise State University, Boise, Idaho, USA
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46
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Bouchard R, Sahin O, Emelianov S. Ultrasound-guided photoacoustic imaging: current state and future development. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2014; 61:450-66. [PMID: 24569250 DOI: 10.1109/tuffc.2014.2930] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Photoacoustic imaging, frequently coregistered with ultrasonic imaging, can provide functional and cellular/molecular information about tissue within the anatomical landmarks of an imaged region. This review details the fundamentals of photoacoustic imaging and its most promising imaging applications. Particular attention is paid to photoacoustic imaging's relationship with ultrasound, focusing on distinct differences and similarities between the two modalities and highlighting the mutual benefit of using both concurrently in certain preclinical and clinical applications. Much like its origins as an imaging modality were intertwined with ultrasonic imaging (namely, its acoustic transducers and hardware), the future of photoacoustic imaging-particularly in the clinical arena-similarly depends on ultrasound and its time-tested ability to provide real-time visualization of soft tissue.
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47
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Xie Z, Chen SL, Fabiilli ML, Fowlkes JB, Shung KK, Zhou Q, Carson PL, Wang X. Simultaneous viewing of individual cells and ambient microvasculature using optical absorption and fluorescence contrasts. Mol Imaging 2014; 12. [PMID: 24447615 DOI: 10.2310/7290.2013.00064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Viewing individual cells and ambient microvasculature simultaneously is crucial for understanding tumor angiogenesis and microenvironments. We developed a confocal fluorescence microscopy (CFM) and photoacoustic microscopy (PAM) dual-modality imaging system that can assess fluorescent contrast and optical absorption contrast in biologic samples simultaneously. After staining tissues with fluorescent dye at an appropriate concentration, each laser pulse can generate not only sufficient fluorescent signals from cells for CFM but also sufficient photoacoustic signals from microvessels for PAM. To explore the potential of this system for diagnosis of bladder cancer, experiments were conducted on a rat bladder model. The CFM image depicts the morphology of individual cells, showing not only large polygonal umbrella cells but also intracellular components. The PAM image acquired at the same time provides complementary information on the microvascular distribution in the bladder wall, ranging from large vessels to capillaries. This device provides an opportunity to realize both histologic assay and microvascular characterization simultaneously. The combination of the information of individual cells and local microvasculature in the bladder offers the capability of envisioning the viability and activeness of these cells and holds promise for more comprehensive study of bladder cancer in vivo.
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Hochreiner A, Bauer-Marschallinger J, Burgholzer P, Jakoby B, Berer T. Non-contact photoacoustic imaging using a fiber based interferometer with optical amplification. BIOMEDICAL OPTICS EXPRESS 2013; 4:2322-31. [PMID: 24298397 PMCID: PMC3829530 DOI: 10.1364/boe.4.002322] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 09/23/2013] [Indexed: 05/04/2023]
Abstract
In photoacoustic imaging the ultrasonic signals are usually detected by contacting transducers. For some applications contact with the tissue should be avoided. As alternatives to contacting transducers interferometric means can be used to acquire photoacoustic signals remotely. In this paper we report on non-contact three and two dimensional photoacoustic imaging using an optical fiber-based Mach-Zehnder interferometer. A detection beam is transmitted through an optical fiber network onto the surface of the specimen. Back reflected light is collected and coupled into the same optical fiber. To achieve a high signal/noise ratio the reflected light is amplified by means of optical amplification with an erbium doped fiber amplifier before demodulation. After data acquisition the initial pressure distribution is reconstructed by a Fourier domain reconstruction algorithm. We present remote photoacoustic imaging of a tissue mimicking phantom and on chicken skin.
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Affiliation(s)
- Armin Hochreiner
- Research Center for Non-Destructive Testing GmbH (RECENDT), Altenberger Straße 69, 4040 Linz, Austria
| | | | - Peter Burgholzer
- Research Center for Non-Destructive Testing GmbH (RECENDT), Altenberger Straße 69, 4040 Linz, Austria
| | - Bernhard Jakoby
- Institute for Microelectronics and Microsensors, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
| | - Thomas Berer
- Research Center for Non-Destructive Testing GmbH (RECENDT), Altenberger Straße 69, 4040 Linz, Austria
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Blatter C, Grajciar B, Zou P, Wieser W, Verhoef AJ, Huber R, Leitgeb RA. Intrasweep phase-sensitive optical coherence tomography for noncontact optical photoacoustic imaging. OPTICS LETTERS 2012; 37:4368-70. [PMID: 23114298 DOI: 10.1364/ol.37.004368] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
We introduce a method to extract the photoacoustic (PA) signal from the phase time evolution of an optical coherence tomography (OCT) swept source spectral sweep. This all-optical detection is achieved in a noncontact fashion directly on the sample surface by using its specular reflection. High-speed measurement and referencing allow for close to shot noise limited phase-sensitive detection. It offers a simple way to perform OCT and PA imaging by sharing the same system components.
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Affiliation(s)
- Cedric Blatter
- Group of Biomedical Optics, Center of Medical Physics and Biomedical Engineering, Medical University Vienna, Vienna, Austria
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Rousseau G, Gauthier B, Blouin A, Monchalin JP. Non-contact biomedical photoacoustic and ultrasound imaging. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:061217. [PMID: 22734747 DOI: 10.1117/1.jbo.17.6.061217] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The detection of ultrasound in photoacoustic tomography (PAT) usually relies on ultrasonic transducers in contact with the biological tissue through a coupling medium. This is a major drawback for important potential applications such as surgery. Here we report the use of a remote optical method, derived from industrial laser-ultrasonics, to detect ultrasound in tissues. This approach enables non-contact PAT (NCPAT) without exceeding laser exposure safety limits. The sensitivity of the method is based on the use of suitably shaped detection laser pulses and a confocal Fabry-Perot interferometer in differential configuration. Reliable image reconstruction is obtained by measuring remotely the surface profile of the tissue with an optical coherence tomography system. The proposed method also allows non-contact ultrasound imaging (US) by applying a second reconstruction algorithm to the data acquired for NCPAT. Endogenous and exogenous inclusions exhibiting optical and acoustic contrasts were detected ex vivo in chicken breast and calf brain specimens. Inclusions down to 0.3 mm in size were detected at depths exceeding 1 cm. The method could expand the scope of photoacoustic and US to in-vivo biomedical applications where contact is impractical.
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Affiliation(s)
- Guy Rousseau
- Industrial Materials Institute, National Research Council of Canada, 75 De Mortagne Boulevard, Boucherville, Québec J4B 6Y4, Canada.
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