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Bjegovic K, Sun L, Pandey P, Grilj V, Ballesteros-Zebadua P, Paisley R, Gonzalez G, Wang S, Vozenin MC, Limoli CL, Xiang SL. 4D in vivodosimetry for a FLASH electron beam using radiation-induced acoustic imaging. Phys Med Biol 2024; 69:115053. [PMID: 38722574 DOI: 10.1088/1361-6560/ad4950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2024] [Accepted: 05/09/2024] [Indexed: 06/01/2024]
Abstract
Objective. The primary goal of this research is to demonstrate the feasibility of radiation-induced acoustic imaging (RAI) as a volumetric dosimetry tool for ultra-high dose rate FLASH electron radiotherapy (FLASH-RT) in real time. This technology aims to improve patient outcomes by accurate measurements ofin vivodose delivery to target tumor volumes.Approach. The study utilized the FLASH-capable eRT6 LINAC to deliver electron beams under various doses (1.2 Gy pulse-1to 4.95 Gy pulse-1) and instantaneous dose rates (1.55 × 105Gy s-1to 2.75 × 106Gy s-1), for imaging the beam in water and in a rabbit cadaver with RAI. A custom 256-element matrix ultrasound array was employed for real-time, volumetric (4D) imaging of individual pulses. This allowed for the exploration of dose linearity by varying the dose per pulse and analyzing the results through signal processing and image reconstruction in RAI.Main Results. By varying the dose per pulse through changes in source-to-surface distance, a direct correlation was established between the peak-to-peak amplitudes of pressure waves captured by the RAI system and the radiochromic film dose measurements. This correlation demonstrated dose rate linearity, including in the FLASH regime, without any saturation even at an instantaneous dose rate up to 2.75 × 106Gy s-1. Further, the use of the 2D matrix array enabled 4D tracking of FLASH electron beam dose distributions on animal tissue for the first time.Significance. This research successfully shows that 4Din vivodosimetry is feasible during FLASH-RT using a RAI system. It allows for precise spatial (∼mm) and temporal (25 frames s-1) monitoring of individual FLASH beamlets during delivery. This advancement is crucial for the clinical translation of FLASH-RT as enhancing the accuracy of dose delivery to the target volume the safety and efficacy of radiotherapeutic procedures will be improved.
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Affiliation(s)
- Kristina Bjegovic
- The Department of Biomedical Engineering, University of California, Irvine, CA 92617, United States of America
| | - Leshan Sun
- The Department of Biomedical Engineering, University of California, Irvine, CA 92617, United States of America
| | - Prabodh Pandey
- Department of Radiological Sciences, University of California, Irvine, Irvine, CA 92697, United States of Americaica
| | - Veljko Grilj
- Laboratory of Radiation Oncology, Radiation Oncology Service and Oncology Department, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Paola Ballesteros-Zebadua
- Laboratory of Radiation Oncology, Radiation Oncology Service and Oncology Department, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
- Laboratory of Medical Physics, National Institute of Neurology and Neurosurgery, Mexico City, Mexico
| | - Ryan Paisley
- Laboratory of Radiation Oncology, Radiation Oncology Service and Oncology Department, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | - Gilberto Gonzalez
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, United States of America
| | - Siqi Wang
- The Department of Biomedical Engineering, University of California, Irvine, CA 92617, United States of America
| | - Marie Catherine Vozenin
- Laboratory of Radiation Oncology, Radiation Oncology Service and Oncology Department, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
- Sector of Radiobiology applied to Radiation Oncology, Radiation Oncology Service, Geneva University Hospital and University of Geneva, Geneva, Switzerland
| | - Charles L Limoli
- Department of Radiation Oncology, University of California, Irvine, Irvine, CA 92697-2695, United States of America
| | - Shawn Liangzhong Xiang
- The Department of Biomedical Engineering, University of California, Irvine, CA 92617, United States of America
- Department of Radiological Sciences, University of California, Irvine, Irvine, CA 92697, United States of Americaica
- Beckman Laser Institute & Medical Clinic, University of California, Irvine, Irvine, CA 92612, United States of America
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Choi S, Park S, Kim J, Kim H, Cho S, Kim S, Park J, Kim C. X-ray free-electron laser induced acoustic microscopy (XFELAM). PHOTOACOUSTICS 2024; 35:100587. [PMID: 38312809 PMCID: PMC10835452 DOI: 10.1016/j.pacs.2024.100587] [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: 10/10/2023] [Revised: 01/11/2024] [Accepted: 01/11/2024] [Indexed: 02/06/2024]
Abstract
The X-ray free-electron laser (XFEL) has remarkably advanced X-ray imaging technology and enabled important scientific achievements. The XFEL's extremely high power, short pulse width, low emittance, and high coherence make possible such diverse imaging techniques as absorption/emission spectroscopy, diffraction imaging, and scattering imaging. Here, we demonstrate a novel XFEL-based imaging modality that uses the X-ray induced acoustic (XA) effect, which we call X-ray free-electron laser induced acoustic microscopy (XFELAM). Initially, we verified the XA effect by detecting XA signals from various materials, then we validated the experimental results with simulation outcomes. Next, in resolution experiments, we successfully imaged a patterned tungsten target with drilled various-sized circles at a spatial resolution of 7.8 ± 5.1 µm, which is the first micron-scale resolution achieved by XA imaging. Our results suggest that the novel XFELAM can expand the usability of XFEL in various areas of fundamental scientific research.
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Affiliation(s)
- Seongwook Choi
- Pohang University of Science and Technology (POSTECH), Medical Device Innovation Center, Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, Medical Science and Engineering, 77 Cheongam-ro, Pohang 37673, Republic of Korea
| | - Sinyoung Park
- Pohang University of Science and Technology (POSTECH), Medical Device Innovation Center, Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, Medical Science and Engineering, 77 Cheongam-ro, Pohang 37673, Republic of Korea
| | - Jiwoong Kim
- Pohang University of Science and Technology (POSTECH), Medical Device Innovation Center, Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, Medical Science and Engineering, 77 Cheongam-ro, Pohang 37673, Republic of Korea
| | - Hyunhee Kim
- Pohang University of Science and Technology (POSTECH), Medical Device Innovation Center, Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, Medical Science and Engineering, 77 Cheongam-ro, Pohang 37673, Republic of Korea
| | - Seonghee Cho
- Pohang University of Science and Technology (POSTECH), Medical Device Innovation Center, Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, Medical Science and Engineering, 77 Cheongam-ro, Pohang 37673, Republic of Korea
| | - Sunam Kim
- Pohang Accelerator Laboratory, 77 Cheongam-ro, Pohang 37673, Republic of Korea
| | - Jaeku Park
- Pohang Accelerator Laboratory, 77 Cheongam-ro, Pohang 37673, Republic of Korea
| | - Chulhong Kim
- Pohang University of Science and Technology (POSTECH), Medical Device Innovation Center, Department of Electrical Engineering, Convergence IT Engineering, Mechanical Engineering, Medical Science and Engineering, 77 Cheongam-ro, Pohang 37673, Republic of Korea
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Sun L, Gonzalez G, Pandey PK, Wang S, Kim K, Limoli C, Chen Y, Xiang L. Towards quantitative in vivo dosimetry using x-ray acoustic computed tomography. Med Phys 2023; 50:6894-6907. [PMID: 37203253 PMCID: PMC10656364 DOI: 10.1002/mp.16476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 04/05/2023] [Accepted: 04/30/2023] [Indexed: 05/20/2023] Open
Abstract
BACKGROUND Radiation dosimetry is essential for radiation therapy (RT) to ensure that radiation dose is accurately delivered to the tumor. Despite its wide use in clinical intervention, the delivered radiation dose can only be planned and verified via simulation. This makes precision radiotherapy challenging while in-line verification of the delivered dose is still absent in the clinic. X-ray-induced acoustic computed tomography (XACT) has recently been proposed as an imaging tool for in vivo dosimetry. PURPOSE Most of the XACT studies focus on localizing the radiation beam. However, it has not been studied for its potential for quantitative dosimetry. The aim of this study was to investigate the feasibility of using XACT for quantitative in vivo dose reconstruction during radiotherapy. METHODS Varian Eclipse system was used to generate simulated uniform and wedged 3D radiation field with a size of 4 cm× $ \times \ $ 4 cm. In order to use XACT for quantitative dosimetry measurements, we have deconvoluted the effects of both the x-ray pulse shape and the finite frequency response of the ultrasound detector. We developed a model-based image reconstruction algorithm to quantify radiation dose in vivo using XACT imaging, and universal back-projection (UBP) reconstruction is used as comparison. The reconstructed dose was calibrated before comparing it to the percent depth dose (PDD) profile. Structural similarity index matrix (SSIM) and root mean squared error (RMSE) are used for numeric evaluation. Experimental signals were acquired from 4 cm× $ \times \ $ 4 cm radiation field created by Linear Accelerator (LINAC) at depths of 6, 8, and 10 cm beneath the water surface. The acquired signals were processed before reconstruction to achieve accurate results. RESULTS Applying model-based reconstruction algorithm with non-negative constraints successfully reconstructed accurate radiation dose in 3D simulation study. The reconstructed dose matches well with the PDD profile after calibration in experiments. The SSIMs between the model-based reconstructions and initial doses are over 85%, and the RMSEs of model-based reconstructions are eight times lower than the UBP reconstructions. We have also shown that XACT images can be displayed as pseudo-color maps of acoustic intensity, which correspond to different radiation doses in the clinic. CONCLUSION Our results show that the XACT imaging by model-based reconstruction algorithm is considerably more accurate than the dose reconstructed by UBP algorithm. With proper calibration, XACT is potentially applicable to the clinic for quantitative in vivo dosimetry across a wide range of radiation modalities. In addition, XACT's capability of real-time, volumetric dose imaging seems well-suited for the emerging field of ultrahigh dose rate "FLASH" radiotherapy.
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Affiliation(s)
- Leshan Sun
- Department of Biomedical Engineering, University of California, Irvine, California, USA
| | - Gilberto Gonzalez
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Prabodh Kumar Pandey
- Department of Radiological Sciences, University of California at Irvine, Irvine, California, USA
| | - Siqi Wang
- Department of Biomedical Engineering, University of California, Irvine, California, USA
| | - Kaitlyn Kim
- Department of Biomedical Engineering, University of California, Irvine, California, USA
| | - Charles Limoli
- Department of Radiation Oncology, University of California Irvine, Medical Sciences I, Irvine, California, USA
| | - Yong Chen
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Liangzhong Xiang
- Department of Biomedical Engineering, University of California, Irvine, California, USA
- Department of Radiological Sciences, University of California at Irvine, Irvine, California, USA
- Beckman Laser Institute, University of California at Irvine, Irvine, California, USA
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Pandey PK, Wang S, Sun L, Xing L, Xiang L. Model-Based 3-D X-Ray Induced Acoustic Computerized Tomography. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2023; 7:532-543. [PMID: 38046375 PMCID: PMC10691826 DOI: 10.1109/trpms.2023.3238017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
X-ray-induced acoustic (XA) computerized tomography (XACT) is an evolving imaging technique that aims to reconstruct the X-ray energy deposition from XA measurements. Main challenges in XACT are the poor signal-to-noise ratio and limited field-of-view, which cause artifacts in the images. We demonstrate the efficacy of model-based (MB) algorithms for three-dimensional XACT and compare with the traditional algorithms. The MB algorithm is based on iterative, matrix-free approach for regularized-least-squares minimization corresponding to XACT. The matrix-free-LSQR (MF-LSQR) and the non-iterative model-backprojection (MBP) reconstructions were evaluated and compared with universal backprojection (UBP), time-reversal (TR) and fast-Fourier transform (FFT)-based reconstructions for numerical and experimental XACT datasets. The results demonstrate the capability of MF-LSQR algorithm to reduce noisy artifacts thus yielding better reconstructions. MBP and MF-LSQR algorithms perform particularly well with the experimental XACT dataset, where noise in signals significantly affects the reconstruction of the target in UBP and FFT-based reconstructions. The TR reconstruction for experimental XACT are comparable to MF-LSQR, but takes thrice as much time and filters the frequency components greater than maximum frequency supported by the grid, resulting loss of resolution. The MB algorithms are able to overcome the challenges in XACT and hence are vital for the clinical translation of XACT.
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Affiliation(s)
- Prabodh Kumar Pandey
- Department of Radiological Sciences, University of California, Irvine, CA, 92697, USA
| | - Siqi Wang
- Department of Biomedical Engineering, University of California, Irvine, CA 92617, USA
| | - Leshan Sun
- Department of Biomedical Engineering, University of California, Irvine, CA 92617, USA
| | - Lei Xing
- Department of Radiological Sciences, University of California, Irvine, CA, 92697, USA.; Department of Biomedical Engineering, University of California, Irvine, CA 92617, USA.; Beckman Laser Institute, University of California, Irvine, CA 92612, USA
| | - Liangzhong Xiang
- Division of Medical Physics, Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA,94305, USA
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Lyu Q, Neph R, Sheng K. Tomographic detection of photon pairs produced from high-energy X-rays for the monitoring of radiotherapy dosing. Nat Biomed Eng 2023; 7:323-334. [PMID: 36280738 PMCID: PMC10038801 DOI: 10.1038/s41551-022-00953-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 09/14/2022] [Indexed: 01/07/2023]
Abstract
Measuring the radiation dose reaching a patient's body is difficult. Here we report a technique for the tomographic reconstruction of the location of photon pairs originating from the annihilation of positron-electron pairs produced by high-energy X-rays travelling through tissue. We used Monte Carlo simulations on pre-recorded data from tissue-mimicking phantoms and from a patient with a brain tumour to show the feasibility of this imaging modality, which we named 'pair-production tomography', for the monitoring of radiotherapy dosing. We simulated three image-reconstruction methods, one applicable to a pencil X-ray beam scanning through a region of interest, and two applicable to the excitation of tissue volumes via broad beams (with temporal resolution sufficient to identify coincident photon pairs via filtered back projection, or with higher temporal resolution sufficient for the estimation of a photon's time-of-flight). In addition to the monitoring of radiotherapy dosing, we show that image contrast resulting from pair-production tomography is highly proportional to the material's atomic number. The technique may thus also allow for element mapping and for soft-tissue differentiation.
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Affiliation(s)
- Qihui Lyu
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USA
| | - Ryan Neph
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USA
| | - Ke Sheng
- Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USA.
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Chen F, Sun M, Chen R, Li C, Shi J. Absolute Grüneisen parameter measurement in deep tissue based on X-ray-induced acoustic computed tomography. BIOMEDICAL OPTICS EXPRESS 2023; 14:1205-1215. [PMID: 36950240 PMCID: PMC10026575 DOI: 10.1364/boe.483490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
The Grüneisen parameter is a primary parameter of the initial sound pressure signal in the photoacoustic effect, which can provide unique biological information and is related to the temperature change information of an object. The accurate measurement of this parameter is of great significance in biomedical research. Combining X-ray-induced acoustic tomography and conventional X-ray computed tomography, we proposed a method to obtain the absolute Grüneisen parameter. The theory development, numerical simulation, and biomedical application scenarios are discussed. The results reveal that our method not only can determine the Grüneisen parameter but can also obtain the body internal temperature distribution, presenting its potential in the diagnosis of a broad range of diseases.
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Li Y, Samant P, Cochran C, zhao Y, Keyak JH, Hu X, Yu A, Xiang L. The feasibility study of XACT imaging for characterizing osteoporosis. Med Phys 2022; 49:7694-7702. [PMID: 35962866 PMCID: PMC10567061 DOI: 10.1002/mp.15906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 07/08/2022] [Accepted: 07/21/2022] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Osteoporosis is a progressive bone disease that is characterized by a decrease in bone mass and the deterioration in bone microarchitecture, which might be related to age and space travel. An unmet need exists for the development of novel imaging technologies to characterize osteoporosis. PURPOSE The purpose of our study is to investigate the feasibility of X-ray-induced acoustic computed tomography (XACT) imaging for osteoporosis detection. METHODS An in-house simulation workflow was developed to assess the ability of XACT for osteoporosis detection. To evaluate this simulation workflow, a three-dimensional digital bone phantom for XACT imaging was created by a series of two-dimensional micro-computed tomography (micro-CT) slices of normal and osteoporotic bones in mice. In XACT imaging, the initial acoustic pressure rise caused by the X-ray induce acoustic (XA) effect is proportional to bone density. First, region growing was deployed for image segmentation of different materials inside the bone. Then k-wave simulations were deployed to model XA wave propagation, attenuation, and detection. Finally, the time-varying pressure signals detected at each transducer location were used to reconstruct the XACT image with a time-reversal reconstruction algorithm. RESULTS Through the simulated XACT images, cortical porosity has been calculated, and XA signal spectra slopes have been analyzed for the detection of osteoporosis. The results have demonstrated that osteoporotic bones have lower bone mineral density and higher spectra slopes. These findings from XACT images were in good agreement with porosity calculation from micro-CT images. CONCLUSION This work explores the feasibility of using XACT imaging as a new imaging tool for Osteoporosis detection. Considering that acoustic signals are generated by X-ray absorption, XACT imaging can be combined with traditional X-ray imaging that holds potential for clinical management of osteoporosis and other bone diseases.
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Affiliation(s)
- Yizhou Li
- Department of Orthopedics Trauma and Microsurgery, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China
- School of Electrical and Computer Engineering, The University of Oklahoma, Norman, Oklahoma, USA
- Department of Orthopedics, Affiliated Hospital of Inner Mongolia Medical University, Inner Mongolia, China
| | - Pratik Samant
- School of Electrical and Computer Engineering, The University of Oklahoma, Norman, Oklahoma, USA
- Department of Oncology, University of Oxford, Oxford, UK
| | - Christian Cochran
- School of Electrical and Computer Engineering, The University of Oklahoma, Norman, Oklahoma, USA
| | - Yue zhao
- School of Electrical and Computer Engineering, The University of Oklahoma, Norman, Oklahoma, USA
| | - Joyce H. Keyak
- Department of Radiological Sciences, University of California, Irvine, Irvine, California, USA
| | - Xiang Hu
- Department of Orthopedics Trauma and Microsurgery, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China
| | - Aixi Yu
- Department of Orthopedics Trauma and Microsurgery, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China
| | - Liangzhong Xiang
- School of Electrical and Computer Engineering, The University of Oklahoma, Norman, Oklahoma, USA
- Department of Radiological Sciences, University of California, Irvine, Irvine, California, USA
- Department of Biomedical Engineering, University of California, Irvine, Irvine, California, USA
- Beckman Laser Institute & Medical Clinic, University of California, Irvine, Irvine, California, USA
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Pandey PK, Aggrawal HO, Wang S, Kim K, Liu A, Xiang L. Ring artifacts removal in X-ray-induced acoustic computed tomography. JOURNAL OF INNOVATIVE OPTICAL HEALTH SCIENCES 2022; 15:2250017. [PMID: 38645738 PMCID: PMC11031265 DOI: 10.1142/s1793545822500171] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
X-ray-induced acoustic computed tomography (XACT) is a hybrid imaging modality for detecting X-ray absorption distribution via ultrasound emission. It facilitates imaging from a single projection X-ray illumination, thus reducing the radiation exposure and improving imaging speed. Nonuniform detector response caused by the interference between multichannel data acquisition for ring array transducers and amplifier systems yields ring artifacts in the reconstructed XACT images, which compromises the image quality. We propose model-based algorithms for ring artifacts corrected XACT imaging and demonstrate their efficacy on numerical and experimental measurements. The corrected reconstructions indicate significantly reduced ring artifacts as compared to their conventional counterparts.
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Affiliation(s)
- Prabodh Kumar Pandey
- Department of Radiological Sciences, University of California, Irvine, CA 92697, USA
| | - Hari Om Aggrawal
- Institute of Mathematics and Image Computing, University of Lübeck, Germany
- Independent Technical Consultant, India
| | - Siqi Wang
- Department of Biomedical Engineering, University of California, Irvine, CA 92617, USA
| | - Kaitlyn Kim
- Department of Biomedical Engineering, University of California, Irvine, CA 92617, USA
| | - An Liu
- Department of Radiation Oncology, City of Hope National Medical Center, Duarte CA 91010, USA
| | - Liangzhong Xiang
- Department of Radiological Sciences, University of California, Irvine, CA 92697, USA
- Department of Biomedical Engineering, University of California, Irvine, CA 92617, USA
- Beckman Laser Institute, University of California, Irvine, CA 92612, USA
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Choi S, Park S, Pyo A, Kim DY, Min JJ, Lee C, Kim C. In situ x-ray-induced acoustic computed tomography with a contrast agent: a proof of concept. OPTICS LETTERS 2022; 47:90-93. [PMID: 34951888 DOI: 10.1364/ol.447618] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 11/29/2021] [Indexed: 06/14/2023]
Abstract
X-ray-induced acoustic computed tomography (XACT) has shown great potential as a hybrid imaging modality for real-time non-invasive x-ray dosimetry and low-dose three-dimensional (3D) imaging. While promising, one drawback of the XACT system is the underlying low signal-to-noise ratio (SNR), limiting its in vivo clinical use. In this Letter, we propose the first use of a conventional x-ray computed tomography contrast agent, Gastrografin, for improving the SNR of in situ XACT imaging. We obtained 3D volumetric XACT images of a mouse's stomach with orally injected Gastrografin establishing the proposal's feasibility. Thus, we believe, in the future, our proposed technique will allow in vivo imaging and expand or complement conventional x-ray modalities, such as radiotherapy and accelerators.
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Pandey PK, Wang S, Aggrawal HO, Bjegovic K, Boucher S, Xiang L. Model-Based X-Ray-Induced Acoustic Computed Tomography. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2021; 68:3560-3569. [PMID: 34310297 PMCID: PMC8739265 DOI: 10.1109/tuffc.2021.3098501] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
X-ray-induced acoustic computed tomography (XACT) provides X-ray absorption-based contrast with acoustic detection. For its clinical translation, XACT imaging often has a limited field of view. This can result in image artifacts and overall loss of quantification accuracy. In this article, we aim to demonstrate model-based XACT image reconstruction to address these problems. An efficient matrix-free implementation of the regularized LSQR (MF-LSQR)-based minimization scheme and a noniterative model back-projection (MBP) scheme for computing XACT reconstructions have been demonstrated in this article. The proposed algorithms have been numerically validated and then used to perform reconstructions from experimental measurements obtained from an XACT setup. While the commonly used back-projection (BP) algorithm produces limited-view and noisy artifacts in the region of interest (ROI), model-based LSQR minimization overcomes these issues. The model-based algorithms also reduce the ring artifacts caused due to the nonuniformity response of the multichannel data acquisition. Using the model-based reconstruction algorithms, we are able to obtain reasonable XACT reconstructions for acoustic measurements of up to 120° view. Although the MBP is more efficient than the model-based LSQR algorithm, it provides only the structural information of the ROI. Overall, it has been demonstrated that the model-based image reconstruction yields better image quality for XACT than the standard BP. Moreover, the combination of model-based image reconstruction with different regularization methods can solve the limited-view problem for XACT imaging (in many realistic cases where the full-view dataset is unavailable), and hence pave the way for future clinical translation.
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Wang S, Ivanov V, Pandey PK, Xiang L. X-ray-induced acoustic computed tomography (XACT) imaging with single-shot nanosecond x-ray. APPLIED PHYSICS LETTERS 2021; 119:183702. [PMID: 34776515 PMCID: PMC8566011 DOI: 10.1063/5.0071911] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 10/12/2021] [Indexed: 05/20/2023]
Abstract
X-ray-induced acoustic computed tomography (XACT) has emerged as a promising imaging modality with broad applications in both biomedicine and nondestructive testing. The previous XACT imaging systems require thousands of averages to achieve reasonable images. Here, we report the experimental demonstration of single-shot XACT imaging of a metal object using a single-shot 50 ns x-ray pulse. A two-stage dedicated amplification and a 128-channel parallel data acquisition configuration were introduced for XACT imaging to enable sufficient acoustic signal amplification and maintain an overall low noise level for single-shot XACT imaging. Details of the system design are presented; the improved signal-to-noise ratio (>23 dB) and image reconstruction have been demonstrated with a ring ultrasound transducer array imaging system. The study paves the way for realizing real-time XACT imaging and its potential applications in image-guided intervention.
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Affiliation(s)
- Siqi Wang
- The Department of Biomedical Engineering, University of California, Irvine, California 92617, USA
| | | | - Prabodh Kumar Pandey
- The Department of Radiological Sciences, University of California, Irvine, California 92617, USA
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Wang M, Samant P, Wang S, Merill J, Chen Y, Ahmad S, Li D, Xiang L. Towards in vivo Dosimetry for Prostate Radiotherapy with a Transperineal Ultrasound Array: A Simulation Study. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2021; 5:373-382. [PMID: 33969250 PMCID: PMC8104130 DOI: 10.1109/trpms.2020.3015109] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
X-ray-induced acoustic computed tomography (XACT) is a promising imaging modality to monitor the position of the radiation beam and the deposited dose during external beam radiotherapy delivery. The purpose of this study was to investigate the feasibility of using a transperineal ultrasound transducer array for XACT imaging to guide the prostate radiotherapy. A customized two-dimensional (2D) matrix ultrasound transducer array with 10000 (100×100 elements) ultrasonic sensors with a central frequency of 1 MHz was designed on a 5 cm×5 cm plane to optimize three-dimensional (3D) volumetric imaging. The CT scan and dose treatment plan for a prostate patient undergoing intensity modulated radiation therapy (IMRT) were obtained. In-house simulation was developed to model the time varying X-ray induced acoustic (XA) signals detected by the transperineal ultrasound array. A 3D filtered back projection (FBP) algorithm has been used for 3D XACT image reconstruction. Results of this study will greatly enhance the potential of XACT imaging for real time in vivo dosimetry during radiotherapy.
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Affiliation(s)
- Mengxiao Wang
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, School of Physics and Electronics, Shandong Normal University, Jinan, Shandong, 250358, China
| | - Pratik Samant
- Stephenson School of Biomedical Engineering, University of Oklahoma, Norman, OK, 73019, USA
| | - Siqi Wang
- School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK, 73019, USA
| | - Jack Merill
- Stephenson School of Biomedical Engineering, University of Oklahoma, Norman, OK, 73019, USA
| | - Yong Chen
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma city, OK, USA
| | - Salahuddin Ahmad
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma city, OK, USA
| | - Dengwang Li
- Shandong Province Key Laboratory of Medical Physics and Image Processing Technology, School of Physics and Electronics, Shandong Normal University, Jinan, Shandong, 250358, China
| | - Liangzhong Xiang
- School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK, 73019, USA
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13
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Robertson E, Samant P, Wang S, Tran T, Ji X, Xiang L. X-Ray-Induced Acoustic Computed Tomography (XACT): Initial Experiment on Bone Sample. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2021; 68:1073-1080. [PMID: 33085608 PMCID: PMC8274389 DOI: 10.1109/tuffc.2020.3032779] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
X-ray-induced acoustic computed tomography (XACT) is a unique hybrid imaging modality that combines high X-ray absorption contrast with high ultrasonic resolution. X-ray radiography and computerized tomography (CT) are currently the gold standards for 2-D and 3-D imaging of skeletal tissues though there are important properties of bone, such as elasticity and speed of sound (SOS), that these techniques cannot measure. Ultrasound is capable of measuring such properties though current clinical ultrasound scanners cannot be used to image the interior morphology of bones because they fail to address the complicated physics involved for exact image reconstruction; bone is heterogeneous and composed of layers of both cortical and trabecular bone, which violates assumptions in conventional ultrasound imaging of uniform SOS. XACT, in conjunction with the time-reversal algorithm, is capable of generating precise reconstructions, and by combining elements of both X-ray and ultrasound imaging, XACT is potentially capable of obtaining more information than any single of these techniques at low radiation dose. This article highlights X-ray-induced acoustic detection through linear scanning of an ultrasound transducer and the time-reversal algorithm to produce the first-ever XACT image of a bone sample. The results of this study should prove to enhance the potential of XACT imaging in the evaluation of bone diseases for future clinical use.
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14
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Choi S, Park EY, Park S, Kim JH, Kim C. Synchrotron X-ray induced acoustic imaging. Sci Rep 2021; 11:4047. [PMID: 33603050 PMCID: PMC7893053 DOI: 10.1038/s41598-021-83604-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 02/01/2021] [Indexed: 11/09/2022] Open
Abstract
X-ray induced acoustic imaging (XAI) is an emerging biomedical imaging technique that can visualize X-ray absorption contrast at ultrasound resolution with less ionizing radiation exposure than conventional X-ray computed tomography. So far, medical linear accelerators or industrial portable X-ray tubes have been explored as X-ray excitation sources for XAI. Here, we demonstrate the first feasible synchrotron XAI (sXAI). The synchrotron generates X-rays, with a dominant energy of 4 to 30 keV, a pulse-width of 30 ps, a pulse-repetition period of 2 ns, and a bunch-repetition period of 940 ns. The X-ray induced acoustic (XA) signals are processed in the Fourier domain by matching the signal frequency with the bunch-repetition frequency. We successfully obtained two-dimensional XA images of various lead targets. This novel sXAI tool could complement conventional synchrotron applications.
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Affiliation(s)
- Seongwook Choi
- Department of Electrical Engineering and Creative IT Engineering, Medical Device Innovation Center, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Eun-Yeong Park
- Department of Electrical Engineering and Creative IT Engineering, Medical Device Innovation Center, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Sinyoung Park
- Department of Electrical Engineering and Creative IT Engineering, Medical Device Innovation Center, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Jong Hyun Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Republic of Korea.
- Pohang Accelerator Laboratory, Pohang, Republic of Korea.
| | - Chulhong Kim
- Department of Electrical Engineering and Creative IT Engineering, Medical Device Innovation Center, Pohang University of Science and Technology, Pohang, Republic of Korea.
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang, Republic of Korea.
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15
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Pogue BW, Zhang R, Cao X, Jia JM, Petusseau A, Bruza P, Vinogradov SA. Review of in vivo optical molecular imaging and sensing from x-ray excitation. JOURNAL OF BIOMEDICAL OPTICS 2021; 26:JBO-200308VR. [PMID: 33386709 PMCID: PMC7778455 DOI: 10.1117/1.jbo.26.1.010902] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 11/24/2020] [Indexed: 05/05/2023]
Abstract
SIGNIFICANCE Deep-tissue penetration by x-rays to induce optical responses of specific molecular reporters is a new way to sense and image features of tissue function in vivo. Advances in this field are emerging, as biocompatible probes are invented along with innovations in how to optimally utilize x-ray sources. AIM A comprehensive review is provided of the many tools and techniques developed for x-ray-induced optical molecular sensing, covering topics ranging from foundations of x-ray fluorescence imaging and x-ray tomography to the adaptation of these methods for sensing and imaging in vivo. APPROACH The ways in which x-rays can interact with molecules and lead to their optical luminescence are reviewed, including temporal methods based on gated acquisition and multipoint scanning for improved lateral or axial resolution. RESULTS While some known probes can generate light upon x-ray scintillation, there has been an emergent recognition that excitation of molecular probes by x-ray-induced Cherenkov light is also possible. Emission of Cherenkov radiation requires a threshold energy of x-rays in the high kV or MV range, but has the advantage of being able to excite a broad range of optical molecular probes. In comparison, most scintillating agents are more readily activated by lower keV x-ray energies but are composed of crystalline inorganic constituents, although some organic biocompatible agents have been designed as well. Methods to create high-resolution structured x-ray-optical images are now available, based upon unique scanning approaches and/or a priori knowledge of the scanned x-ray beam geometry. Further improvements in spatial resolution can be achieved by careful system design and algorithm optimization. Current applications of these hybrid x-ray-optical approaches include imaging of tissue oxygenation and pH as well as of certain fluorescent proteins. CONCLUSIONS Discovery of x-ray-excited reporters combined with optimized x-ray scan sequences can improve imaging resolution and sensitivity.
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Affiliation(s)
- Brian W. Pogue
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
- Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, United States
| | - Rongxiao Zhang
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
- Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire, United States
| | - Xu Cao
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
| | - Jeremy Mengyu Jia
- Stanford University School of Medicine, Department of Radiation Oncology, Palo Alto, California, United States
| | - Arthur Petusseau
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
| | - Petr Bruza
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States
| | - Sergei A. Vinogradov
- University of Pennsylvania, Perelman School of Medicine, Department of Biochemistry and Biophysics, Philadelphia, Pennsylvania, United States
- University of Pennsylvania, School of Arts of Sciences, Department of Chemistry, Philadelphia, Pennsylvania, United States
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16
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Li M, Nyayapathi N, Kilian HI, Xia J, Lovell JF, Yao J. Sound Out the Deep Colors: Photoacoustic Molecular Imaging at New Depths. Mol Imaging 2020; 19:1536012120981518. [PMID: 33336621 PMCID: PMC7750763 DOI: 10.1177/1536012120981518] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Photoacoustic tomography (PAT) has become increasingly popular for molecular imaging due to its unique optical absorption contrast, high spatial resolution, deep imaging depth, and high imaging speed. Yet, the strong optical attenuation of biological tissues has traditionally prevented PAT from penetrating more than a few centimeters and limited its application for studying deeply seated targets. A variety of PAT technologies have been developed to extend the imaging depth, including employing deep-penetrating microwaves and X-ray photons as excitation sources, delivering the light to the inside of the organ, reshaping the light wavefront to better focus into scattering medium, as well as improving the sensitivity of ultrasonic transducers. At the same time, novel optical fluence mapping algorithms and image reconstruction methods have been developed to improve the quantitative accuracy of PAT, which is crucial to recover weak molecular signals at larger depths. The development of highly-absorbing near-infrared PA molecular probes has also flourished to provide high sensitivity and specificity in studying cellular processes. This review aims to introduce the recent developments in deep PA molecular imaging, including novel imaging systems, image processing methods and molecular probes, as well as their representative biomedical applications. Existing challenges and future directions are also discussed.
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Affiliation(s)
- Mucong Li
- Department of Biomedical Engineering, 3065Duke University, Durham, NC, USA
| | - Nikhila Nyayapathi
- Department of Biomedical Engineering, 12292University of Buffalo, NY, USA
| | - Hailey I Kilian
- Department of Biomedical Engineering, 12292University of Buffalo, NY, USA
| | - Jun Xia
- Department of Biomedical Engineering, 12292University of Buffalo, NY, USA
| | - Jonathan F Lovell
- Department of Biomedical Engineering, 12292University of Buffalo, NY, USA
| | - Junjie Yao
- Department of Biomedical Engineering, 3065Duke University, Durham, NC, USA
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Matarèse BFE, Lad J, Seymour C, Schofield PN, Mothersill C. Bio-acoustic signaling; exploring the potential of sound as a mediator of low-dose radiation and stress responses in the environment. Int J Radiat Biol 2020; 98:1083-1097. [DOI: 10.1080/09553002.2020.1834162] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Bruno F. E. Matarèse
- Department of Haematology, University of Cambridge, Cambridge, UK
- Department of Physics, University of Cambridge, Cambridge, UK
| | - Jigar Lad
- Department of Physics and Astronomy, McMaster University, Hamilton, Canada
| | - Colin Seymour
- Department of Biology, McMaster University, Hamilton, Canada
| | - Paul N. Schofield
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
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18
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Dai X, Cheng K, Zhao W, Xing L. High-speed X-ray-induced luminescence computed tomography. JOURNAL OF BIOPHOTONICS 2020; 13:e202000066. [PMID: 32445254 PMCID: PMC7598839 DOI: 10.1002/jbio.202000066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 05/18/2020] [Accepted: 05/19/2020] [Indexed: 05/22/2023]
Abstract
X-ray-induced luminescence computed tomography (XLCT) is an emerging molecular imaging. Challenges in improving spatial resolution and reducing the scan time in a whole-body field of view (FOV) still remain for practical in vivo applications. In this study, we present a novel XLCT technique capable of obtaining three-dimensional (3D) images from a single snapshot. Specifically, a customed two-planar-mirror component is integrated into a cone beam XLCT imaging system to obtain multiple optical views of an object simultaneously. Furthermore, a compressive sensing based algorithm is adopted to improve the efficiency of 3D XLCT image reconstruction. Numerical simulations and experiments were conducted to validate the single snapshot X-ray-induced luminescence computed tomography (SS-XLCT). The results show that the 3D distribution of the nanophosphor targets can be visualized much faster than conventional cone beam XLCT imaging method that was used in our comparisons while maintaining comparable spatial resolution as in conventional XLCT imaging. SS-XLCT has the potential to harness the power of XLCT for rapid whole-body in vivo molecular imaging of small animals.
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Affiliation(s)
- Xianjin Dai
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Kai Cheng
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Wei Zhao
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Lei Xing
- Department of Radiation Oncology, Stanford University, Stanford, California
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Samant P, Trevisi L, Ji X, Xiang L. X-ray induced acoustic computed tomography. PHOTOACOUSTICS 2020; 19:100177. [PMID: 32215251 PMCID: PMC7090367 DOI: 10.1016/j.pacs.2020.100177] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/10/2020] [Accepted: 03/10/2020] [Indexed: 05/22/2023]
Abstract
X-ray imaging has proved invaluable in medical diagnoses and non-destructive testing (NDT) in the past century. However, there remain two major limitations: radiation harm and inaccessibility to the sample. A recent imaging modality, X-ray induced acoustic computed tomography (XACT), allows a novel solution. In XACT, x-ray induced excitation causes localized heating (<mK) and thermoelastic expansion. This induces a detectable ultrasonic emission, thereby enabling imaging. XACT has the potential to enable low-dose, fast, 3D imaging requiring only single side access. We discuss the fundamentals of XACT and summarize milestones in its evolution over the past several years since its first demonstration using a Medical Linear Accelerator. We highlight XACT's potential applications in biomedical imaging and NDT, and discuss the latest advanced concepts and future directions.
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Affiliation(s)
- P. Samant
- Stephenson School of Biomedical Engineering, University of Oklahoma, Norman, 73071, USA
- Department of Oncology, University of Oxford, Oxford, OX3 7DQ, UK
| | - L. Trevisi
- Chemical, Biological, & Materials Engineering, University of Oklahoma, Norman, 73071, USA
| | - X. Ji
- School of Electromechanical Engineering, Guangdong University of Technology, Guangzhou, 510006, Guangdong, China
| | - L. Xiang
- Electrical and Computer Engineering, University of Oklahoma, Norman, 73071, USA
- Corresponding author at: 101 David L Boren Blvd Room 2022, Norman, 73071, USA.
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20
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Zheng Y, Samant P, Merill J, Chen Y, Ahmad S, Li D, Xiang L. X-ray-induced acoustic computed tomography for guiding prone stereotactic partial breast irradiation: a simulation study. Med Phys 2020; 47:4386-4395. [PMID: 32428252 PMCID: PMC7674271 DOI: 10.1002/mp.14245] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 04/22/2020] [Accepted: 05/11/2020] [Indexed: 12/31/2022] Open
Abstract
PURPOSE The aim of this study is to investigate the feasibility of x-ray-induced acoustic computed tomography (XACT) as an image guidance tool for tracking x-ray beam location and monitoring radiation dose delivered to the patient during stereotactic partial breast irradiation (SPBI). METHODS An in-house simulation workflow was developed to assess the ability of XACT to act as an in vivo dosimetry tool for SPBI. To evaluate this simulation workflow, a three-dimensional (3D) digital breast phantom was created by a series of two-dimensional (2D) breast CT slices from a patient. Three different tissue types (skin, adipose tissue, and glandular tissue) were segmented and the postlumpectomy seroma was simulated inside the digital breast phantom. A treatment plan was made with three beam angles to deliver radiation dose to the seroma in breast to simulate SPBI. The three beam angles for 2D simulations were 17°, 90° and 159° (couch angles were 0 degrees) while the angles were 90 degrees (couch angles were 0°, 27°, 90°) in 3D simulation. A multi-step simulation platform capable of modelling XACT was developed. First, the dose distribution was converted to an initial pressure distribution. The propagation of this pressure disturbance in the form of induced acoustic waves was then modeled using the k-wave MATLAB toolbox. The waves were then detected by a hemispherical-shaped ultrasound transducer array (6320 transducer locations distributed on the surface of the breast). Finally, the time-varying pressure signals detected at each transducer location were used to reconstruct an image of the initial pressure distribution using a 3D time-reversal reconstruction algorithm. Finally, the reconstructed XACT images of the radiation beams were overlaid onto the structure breast CT. RESULTS It was found that XACT was able to reconstruct the dose distribution of SPBI in 3D. In the reconstructed 3D volumetric dose distribution, the average doses in the GTV (Gross Target Volume) and PTV (Planning Target Volume) were 86.15% and 80.89%, respectively. When compared to the treatment plan, the XACT reconstructed dose distribution in the GTV and PTV had a RMSE (root mean square error) of 2.408 % and 2.299 % over all pixels. The 3D breast XACT imaging reconstruction with time-reversal reconstruction algorithm can be finished within several minutes. CONCLUSIONS This work explores the feasibility of using the novel imaging modality of XACT as an in vivo dosimeter for SPBI radiotherapy. It shows that XACT imaging can provide the x-ray beam location and dose information in deep tissue during the treatment in real time in 3D. This study lays the groundwork for a variety of future studies related to the use of XACT as a dosimeter at different cancer sites.
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Affiliation(s)
- Yue Zheng
- Shandong Key Laboratory of Medical Physics and Image Processing & Shandong Provincial Engineering and Technical Center of Light Manipulations, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China; School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Pratik Samant
- School of Biomedical Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Jack Merill
- School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Yong Chen
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Salahuddin Ahmad
- Department of Radiation Oncology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
| | - Dengwang Li
- Shandong Key Laboratory of Medical Physics and Image Processing & Shandong Provincial Engineering and Technical Center of Light Manipulations, School of Physics and Electronics, Shandong Normal University, Jinan 250358, China
| | - Liangzhong Xiang
- School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019, USA
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21
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Li Y, Samant P, Wang S, Behrooz A, Li D, Xiang L. 3-D X-Ray-Induced Acoustic Computed Tomography With a Spherical Array: A Simulation Study on Bone Imaging. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2020; 67:1613-1619. [PMID: 32286967 PMCID: PMC7394001 DOI: 10.1109/tuffc.2020.2983732] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
X-ray-induced acoustic computed tomography (XACT) is a promising imaging modality combining high X-ray absorption contrast with the 3-D propagation advantages provided by high-resolution ultrasound waves. The purpose of this study was to optimize the configuration of a 3-D XACT imaging system for bone imaging. A 280 ultrasonic sensors with peak frequency of 10 MHz was designed to distribute on a spherical surface to optimize the 3-D volumetric imaging capability. We performed both theoretical calculations and simulations of this optimized XACT imaging configuration on a mouse-sized digital phantom containing various X-ray absorption coefficients. Iteration algorithm based on total variation has been used for 3-D XACT image reconstruction. The spatial resolution of imaging was estimated to about [Formula: see text] along both axial and lateral directions. We simulate XACT imaging of bone microstructures using digital phantoms generated from micro-CT images of real biological samples, showing that XACT imaging can provide high-resolution imaging of the mouse paw. Results of this study will greatly enhance the potential of XACT imaging in the evaluation of bone diseases for future clinical use.
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Affiliation(s)
- Y. Li
- Shandong Key Laboratory of Medical Physics and Image Processing, Shandong Institute of Industrial Technology for Health Sciences and Precision Medicine, School of Physics and Electronics, Shandong Normal University, Jinan, Shandong 250358, China
| | - P. Samant
- The School of Biomedical Engineering at the University of Oklahoma, Norman, US
| | - S. Wang
- The School of Electrical and Computer Engineering at the University of Oklahoma, Norman, US
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22
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Pandey PK, Bharadwaj J, Naik N, Aggrawal HO. One-step fluorescence photoacoustic tomography with the optical radiative transfer model. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2020; 37:1175-1192. [PMID: 32609678 DOI: 10.1364/josaa.389476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 05/13/2020] [Indexed: 06/11/2023]
Abstract
We present adjoint-based Jacobian as well as gradient evaluations and corresponding reconstruction schemes to solve the fully nonlinear, optical radiative transfer modeled one-step fluorescence photoacoustic tomographic (FPAT) problem, which aims to reconstruct the map of absorption coefficient of the exogenous fluorophore from boundary photoacoustic data. The radiative transport equation (RTE) and frequency-domain photoacoustic equation have been employed to model light and photoacoustic wave propagation, respectively. Levenberg-Marquardt and Broyden-Fletcher-Goldfarb-Shanno reconstruction schemes have been used corresponding to the evaluated Jacobians and gradients, respectively. Numerical reconstructions obtained from the two schemes have been validated for scattering-dominant as well as nonscattering-dominant media in 2D. To the best of our knowledge, these are the first one-step FPAT reconstruction results in literature based on the optical RTE model.
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23
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Zhang W, Oraiqat I, Lei H, Carson PL, EI Naqa I, Wang X. Dual-Modality X-Ray-Induced Radiation Acoustic and Ultrasound Imaging for Real-Time Monitoring of Radiotherapy. BME FRONTIERS 2020; 2020:9853609. [PMID: 37849969 PMCID: PMC10521688 DOI: 10.34133/2020/9853609] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 03/29/2020] [Indexed: 10/19/2023] Open
Abstract
Objective. The goal is to increase the precision of radiation delivery during radiotherapy by tracking the movements of the tumor and other surrounding normal tissues due to respiratory and other body motions. Introduction. This work presents the recent advancement of X-ray-induced radiation acoustic imaging (xRAI) technology and the evaluation of its feasibility for real-time monitoring of geometric and morphological misalignments of the X-ray field with respect to the target tissue by combining xRAI with established ultrasound (US) imaging, thereby improving radiotherapy tumor eradication and limiting treatment side effects. Methods. An integrated xRAI and B-mode US dual-modality system was established based on a clinic-ready research US platform. The performance of this dual-modality imaging system was evaluated via experiments on phantoms and ex vivo and in vivo rabbit liver models. Results. This system can alternatively switch between the xRAI and the US modes, with spatial resolutions of 1.1 mm and 0.37 mm, respectively. 300 times signal averaging was required for xRAI to reach a satisfactory signal-to-noise ratio, and a frame rate of 1.1 Hz was achieved with a clinical linear accelerator. The US imaging frame rate was 22 Hz, which is sufficient for real-time monitoring of the displacement of the target due to internal body motion. Conclusion. Our developed xRAI, in combination with US imaging, allows for mapping of the dose deposition in biological samples in vivo, in real-time, during radiotherapy. Impact Statement. The US-based image-guided radiotherapy system presented in this work holds great potential for personalized cancer treatment and better outcomes.
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Affiliation(s)
- Wei Zhang
- Department of Biomedical Engineering, University of Michigan, USA
| | - Ibrahim Oraiqat
- Department of Radiation Oncology, University of Michigan, USA
| | - Hao Lei
- Department of Mechanical Engineering, University of Michigan, USA
| | - Paul L. Carson
- Department of Biomedical Engineering, University of Michigan, USA
- Department of Radiology, University of Michigan, USA
| | - Issam EI Naqa
- Department of Radiation Oncology, University of Michigan, USA
| | - Xueding Wang
- Department of Biomedical Engineering, University of Michigan, USA
- Department of Radiology, University of Michigan, USA
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24
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Forghani F, Mahl A, Patton TJ, Jones BL, Borden MA, Westerly DC, Altunbas C, Miften M, Thomas DH. Simulation of x-ray-induced acoustic imaging for absolute dosimetry: Accuracy of image reconstruction methods. Med Phys 2020; 47:1280-1290. [PMID: 31828781 DOI: 10.1002/mp.13961] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 12/05/2019] [Accepted: 12/05/2019] [Indexed: 01/13/2023] Open
Abstract
PURPOSE Three-dimensional in-vivo dose verification is one of the standing challenges in radiation therapy. X-ray-induced acoustic tomography has recently been proposed as an imaging method for use in in-vivo dosimetry. The aim of this study was to investigate the accuracy of reconstructing three-dimensional (3D) absolute dose using x-ray-induced acoustic tomography. We performed this investigation using two different tomographic dose reconstruction techniques. METHODS Two examples of 3D dose reconstruction techniques for x-ray acoustic imaging are investigated. Dose distributions are calculated for varying field sizes using a clinical treatment planning system. The induced acoustic pressure waves which are generated by the increase in temperature due to the absorption of pulsed MV x-rays are simulated using an advanced numerical modeling package for acoustic wave propagation in the time domain. Two imaging techniques, back projection and iterative time reversal, are used to reconstruct the 3D dose distribution in a water phantom with open fields. Image analysis is performed and reconstructed depth dose curves from x-ray acoustic imaging are compared to the depth dose curves calculated from the treatment planning system. Calculated field sizes from the reconstructed dose profiles by back projection and time reversal are compared to the planned field size to determine their accuracy. The iterative time reversal imaging technique is also used to reconstruct dose in an example clinical dose distribution. Image analysis of this clinical test case is performed using the gamma passing rate. In addition, gamma passing rates are used to validate the stopping criteria in the iterative time reversal method. RESULTS Water phantom simulations showed that back projection does not adequately reconstruct the shape and intensity of the depth dose. When compared to the depth of maximum dose calculated by a treatment planning system, the maximum dose depth by back projection is shifted deeper by 55 and 75 mm for 4 × 4 cm and 10 × 10 cm field sizes, respectively. The reconstructed depth dose by iterative time reversal accurately agrees with the planned depth dose for a 4 × 4 cm field size and is shifted deeper by 12 mm for the 10 × 10 cm field size. When reconstructing field sizes, the back projection method leads to 18% and 35% larger sizes for the 4 × 4 cm and 10 × 10 cm fields, respectively, whereas the iterative time reversal method reconstructs both field sizes with < 2% error. For the clinical dose distribution, we were able to reconstruct the dose delivered by a 1 degree sub-arc with a good accuracy. The reconstructed and planned doses were compared using gamma analysis, with> 96% gamma passing rate at 3%/2 mm. CONCLUSIONS Our results show that the 3D x-ray acoustic reconstructed dose by iterative time reversal is considerably more accurate than the dose reconstructed by back projection. Iterative time reversal imaging has a potential for use in 3D absolute dosimetry.
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Affiliation(s)
- Farnoush Forghani
- Department of Radiation Oncology, Anschutz Medical Campus, University of Colorado, Aurora, CO, 80045, USA
| | - Adam Mahl
- Department of Radiation Oncology, Anschutz Medical Campus, University of Colorado, Aurora, CO, 80045, USA
| | - Taylor J Patton
- Department of Radiation Oncology, Anschutz Medical Campus, University of Colorado, Aurora, CO, 80045, USA
| | - Bernard L Jones
- Department of Radiation Oncology, Anschutz Medical Campus, University of Colorado, Aurora, CO, 80045, USA
| | - Mark A Borden
- Department of Mechanical Engineering, University of Colorado Boulder, Boulder, CO, 80309, USA
| | - David C Westerly
- Department of Radiation Oncology, Anschutz Medical Campus, University of Colorado, Aurora, CO, 80045, USA
| | - Cem Altunbas
- Department of Radiation Oncology, Anschutz Medical Campus, University of Colorado, Aurora, CO, 80045, USA
| | - Moyed Miften
- Department of Radiation Oncology, Anschutz Medical Campus, University of Colorado, Aurora, CO, 80045, USA
| | - David H Thomas
- Department of Radiation Oncology, Anschutz Medical Campus, University of Colorado, Aurora, CO, 80045, USA
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Lee D, Park EY, Choi S, Kim H, Min JJ, Lee C, Kim C. GPU-accelerated 3D volumetric X-ray-induced acoustic computed tomography. BIOMEDICAL OPTICS EXPRESS 2020; 11:752-761. [PMID: 32133222 PMCID: PMC7041460 DOI: 10.1364/boe.381963] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/29/2019] [Accepted: 01/02/2020] [Indexed: 05/29/2023]
Abstract
X-ray acoustic imaging is a hybrid biomedical imaging technique that can acoustically monitor X-ray absorption distribution in biological tissues through the X-ray induced acoustic effect. In this study, we developed a 3D volumetric X-ray-induced acoustic computed tomography (XACT) system with a portable pulsed X-ray source and an arc-shaped ultrasound array transducer. 3D volumetric XACT images are reconstructed via the back-projection algorithm, accelerated by a custom-developed graphics processing unit (GPU) software. Compared with a CPU-based software, the GPU software reconstructs an image over 40 times faster. We have successfully acquired 3D volumetric XACT images of various lead targets, and this work shows that the 3D volumetric XACT system can monitor a high-resolution X-ray dose distribution and image X-ray absorbing structures inside biological tissues.
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Affiliation(s)
- Donghyun Lee
- Departments of Creative IT Engineering, Electrical Engineering, Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang 37674, South Korea
- These authors contributed equally to this work
| | - Eun-Yeong Park
- Departments of Creative IT Engineering, Electrical Engineering, Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang 37674, South Korea
- These authors contributed equally to this work
| | - Seongwook Choi
- Departments of Creative IT Engineering, Electrical Engineering, Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang 37674, South Korea
| | - Hyeongsub Kim
- Departments of Creative IT Engineering, Electrical Engineering, Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang 37674, South Korea
| | - Jung-Joon Min
- Department of Nuclear Medicine, Chonnam National University Medical School and Hwasun Hospital, Chonnam 58128, South Korea
| | - Changho Lee
- Department of Nuclear Medicine, Chonnam National University Medical School and Hwasun Hospital, Chonnam 58128, South Korea
| | - Chulhong Kim
- Departments of Creative IT Engineering, Electrical Engineering, Mechanical Engineering, School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang 37674, South Korea
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Guo H, Wang Q, Qi W, Sun X, Ke B, Xi L. Assessing the development and treatment of rheumatoid arthritis using multiparametric photoacoustic and ultrasound imaging. JOURNAL OF BIOPHOTONICS 2019; 12:e201900127. [PMID: 31251449 DOI: 10.1002/jbio.201900127] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/28/2019] [Accepted: 06/27/2019] [Indexed: 02/05/2023]
Abstract
Rheumatoid arthritis (RA), characterized by polyarthritis, is a chronic, systemic and inflammatory autoimmune disease. In this study, we developed a dual-modality multiparametric photoacoustic and ultrasound imaging technique, and successfully derived multiple parameters such as relative concentration of total hemoglobin (CHbT ), ratio of angiogenesis, joint size and area of synovia to assess the development and treatment of RA. We established a model of adjuvant arthritis using a total number of 15 rats and randomly divided them into three groups: (a) targeted group in which the rats received targeted antirheumatic drugs; (b) nontargeted group in which the rats were treated with nontargeted antirheumatic drugs; (c) control group. We longitudinally monitored the joints of the rats in all three groups for up to 20 days and carried out quantitative analysis to evaluate the development and treatment of RA based on the derived parameters. The results suggest that the proposed dual-modality imaging technique is able to assess the effectiveness of the RA treatment using quantitative hemodynamic and morphological parameters. To show the clinical feasibility of this technique, we performed in vivo joint studies of health volunteers to visualize both structures and inside hemodynamics of the distal interphalangeal joint.
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Affiliation(s)
- Heng Guo
- School of Physics, University of Electronic Science and Technology of China, Chengdu, China.,Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, China
| | - Qin Wang
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, West China School of Pharmacy, Sichuan University, Chengdu, China
| | - Weizhi Qi
- Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, China
| | - Xun Sun
- Key Laboratory of Drug Targeting and Drug Delivery Systems, Ministry of Education, West China School of Pharmacy, Sichuan University, Chengdu, China
| | - Bowen Ke
- Laboratory of Anesthesiology and Critical Care Medicine, Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, China
| | - Lei Xi
- School of Physics, University of Electronic Science and Technology of China, Chengdu, China.,Department of Biomedical Engineering, Southern University of Science and Technology, Shenzhen, China
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Otero J, Felis I, Ardid M, Herrero A. Acoustic Localization of Bragg Peak Proton Beams for Hadrontherapy Monitoring. SENSORS 2019; 19:s19091971. [PMID: 31035504 PMCID: PMC6539756 DOI: 10.3390/s19091971] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 04/23/2019] [Accepted: 04/23/2019] [Indexed: 12/19/2022]
Abstract
Hadrontherapy makes it possible to deliver high doses of energy to cancerous tumors by using the large energy deposition in the Bragg-peak. However, uncertainties in the patient positioning and/or in the anatomical parameters can cause distortions in the calculation of the dose distribution. In order to maximize the effectiveness of heavy particle treatments, an accurate monitoring system of the deposited dose depending on the energy, beam time, and spot size is necessary. The localized deposition of this energy leads to the generation of a thermoacoustic pulse that can be detected using acoustic technologies. This article presents different experimental and simulation studies of the acoustic localization of thermoacoustic pulses captured with a set of sensors around the sample. In addition, numerical simulations have been done where thermo-acoustic pulses are emitted for the specific case of a proton beam of 100 MeV.
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Affiliation(s)
- Jorge Otero
- Institut d'Investigació per a la Gestió Integrada de les Zones Costaneres (IGIC), Universitat Politècnica de València (UPV), Gandia, 46730 València, Spain.
| | - Ivan Felis
- Centro Tecnológico Naval y del Mar (CTN), Fuente Álamo, 30320 Murcia, Spain.
| | - Miguel Ardid
- Institut d'Investigació per a la Gestió Integrada de les Zones Costaneres (IGIC), Universitat Politècnica de València (UPV), Gandia, 46730 València, Spain.
| | - Alicia Herrero
- Institut de Matemàtica Multidisciplinar, Universitat Politècnica de València (UPV), 46022 València, Spain.
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Giza OM, Sánchez-Parcerisa D, Sánchez-Tembleque V, Herraiz JL, Camacho J, Avery S, Udías JM. Photoacoustic dose monitoring in clinical high-energy photon beams. Biomed Phys Eng Express 2019. [DOI: 10.1088/2057-1976/ab04ed] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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29
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Liu S, Zhang R, Zheng Z, Zheng Y. Electromagnetic⁻Acoustic Sensing for Biomedical Applications. SENSORS (BASEL, SWITZERLAND) 2018; 18:E3203. [PMID: 30248969 PMCID: PMC6210000 DOI: 10.3390/s18103203] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 09/20/2018] [Indexed: 12/29/2022]
Abstract
This paper reviews the theories and applications of electromagnetic⁻acoustic (EMA) techniques (covering light-induced photoacoustic, microwave-induced thermoacoustic, magnetic-modulated thermoacoustic, and X-ray-induced thermoacoustic) belonging to the more general area of electromagnetic (EM) hybrid techniques. The theories cover excitation of high-power EM field (laser, microwave, magnetic field, and X-ray) and subsequent acoustic wave generation. The applications of EMA methods include structural imaging, blood flowmetry, thermometry, dosimetry for radiation therapy, hemoglobin oxygen saturation (SO₂) sensing, fingerprint imaging and sensing, glucose sensing, pH sensing, etc. Several other EM-related acoustic methods, including magnetoacoustic, magnetomotive ultrasound, and magnetomotive photoacoustic are also described. It is believed that EMA has great potential in both pre-clinical research and medical practice.
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Affiliation(s)
- Siyu Liu
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
| | - Ruochong Zhang
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
| | - Zesheng Zheng
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
| | - Yuanjin Zheng
- School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore.
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Hickling S, Hobson M, El Naqa I. Characterization of X-Ray Acoustic Computed Tomography for Applications in Radiotherapy Dosimetry. IEEE TRANSACTIONS ON RADIATION AND PLASMA MEDICAL SCIENCES 2018. [DOI: 10.1109/trpms.2018.2801724] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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31
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Lei H, Zhang W, Oraiqat I, Liu Z, Ni J, Wang X, El Naqa I. Toward in vivo dosimetry in external beam radiotherapy using x-ray acoustic computed tomography: A soft-tissue phantom study validation. Med Phys 2018; 45:4191-4200. [PMID: 29956335 DOI: 10.1002/mp.13070] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 05/14/2018] [Accepted: 06/22/2018] [Indexed: 01/28/2023] Open
Abstract
PURPOSE To study, using phantoms made from biological tissues, the feasibility and practical challenges of monitoring the position of the radiation beam and the deposited dose by x-ray acoustic computed tomography (XACT) during external beam radiotherapy delivery. MATERIAL AND METHODS A prototype XACT system with a single immersion ultrasound transducer, which was positioned around the target sample driven by a motor-controlled rotation stage, was used to acquire the x-ray acoustic (XA) signals produced by a medical linear accelerator (Linac) to form an XACT image of the irradiated phantom. To investigate the feasibility of XACT in tracking the position of radiation dose, a large piece of veal liver with embedded fat tissue was imaged and beam misalignments were measured. Next, we explored the sensitivity of XACT in monitoring and quantifying the delivered dose, in which a block of porcine gel was embedded with equally spaced lard cylinders and imaged. The doses on the lard cylinders modulated by physical wedges were quantified from the XACT image and were verified by comparison to measurements from radiochromic films as the gold standard. Then, to simulate how XACT can perform in a targeted tissue in the human body, a porcine gel phantom with lard cylinders covered by different materials (bone, muscle, and air gap, respectively) was also imaged. RESULTS The reconstructed XACT images of the phantoms show congruence with the boundaries of the beam field and the interfaces between the different tissue materials. The beam displacement from the target was tracked properly by the reconstructed XACT images. An intensity difference as small as 2.9% in delivered dose region can be measured from XACT images P = 0.02. The intensities of XACT images were highly correlated to the film measurements with an R2 better than 0.986. The expected variances of dose delivered to different target regions as a result of the difference in attenuation were successfully captured by the XACT images. CONCLUSIONS This study validated the feasibility of XACT in accurately obtaining relative dose maps of tissue-mimicking phantoms. XACT offers a practical method for verifying the beam position against the target and quantifying the relative dose delivered to the target during external beam radiotherapy.
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Affiliation(s)
- Hao Lei
- Department of Mechanical Engineering, University of Michigan, 2300 Hayward Street, Ann Arbor, MI, 48109, USA
| | - Wei Zhang
- Department of Biomedical Engineering, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, MI, 48109, USA
- Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, 236 Baidi Rd, Nankai District, Tianjin, China
| | - Ibrahim Oraiqat
- Department of Radiation Oncology, University of Michigan, 519 W. William St, Argus Bldg. 1, Ann Arbor, 48103-4943, MI, USA
| | - Zhipeng Liu
- Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, 236 Baidi Rd, Nankai District, Tianjin, China
| | - Jun Ni
- Department of Mechanical Engineering, University of Michigan, 2300 Hayward Street, Ann Arbor, MI, 48109, USA
| | - Xueding Wang
- Department of Biomedical Engineering, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, MI, 48109, USA
| | - Issam El Naqa
- Department of Radiation Oncology, University of Michigan, 519 W. William St, Argus Bldg. 1, Ann Arbor, 48103-4943, MI, USA
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Hickling S, Xiang L, Jones KC, Parodi K, Assmann W, Avery S, Hobson M, El Naqa I. Ionizing radiation‐induced acoustics for radiotherapy and diagnostic radiology applications. Med Phys 2018; 45:e707-e721. [DOI: 10.1002/mp.12929] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 02/20/2018] [Accepted: 04/09/2017] [Indexed: 01/29/2023] Open
Affiliation(s)
- Susannah Hickling
- Department of Physics & Medical Physics Unit McGill University 1001 boul Decarie Montreal QC H4A 3J1Canada
| | - Liangzhong Xiang
- School of Electrical and Computer Engineering University of Oklahoma Norman OK 73019USA
| | - Kevin C. Jones
- Department of Radiation Oncology Rush University Medical Center Chicago IL 60612USA
| | - Katia Parodi
- Department of Medical Physics Ludwig‐Maximilians‐Universität Garching b. München 85748Germany
| | - Walter Assmann
- Department of Medical Physics Ludwig‐Maximilians‐Universität Garching b. München 85748Germany
| | - Stephen Avery
- Department of Radiation Oncology University of Pennsylvania Philadelphia PA19104USA
| | - Maritza Hobson
- Medical Physics Unit McGill University Health Centre Montreal QC H4A 3J1Canada
- Department of Oncology Department of Physics & Medical Physics Unit McGill University Montreal QC H4A 3J1Canada
| | - Issam El Naqa
- Department of Radiation Oncology University of Michigan Ann Arbor MI 48103‐4943USA
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Tang S, Yang K, Chen Y, Xiang L. X-ray-induced acoustic computed tomography for 3D breast imaging: A simulation study. Med Phys 2018; 45:1662-1672. [DOI: 10.1002/mp.12829] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 02/12/2018] [Accepted: 02/12/2018] [Indexed: 01/28/2023] Open
Affiliation(s)
- Shanshan Tang
- School of Electrical and Computer Engineering; The University of Oklahoma; Norman OK 73019 USA
| | - Kai Yang
- Department of Radiology; Massachusetts General Hospital; 55 Fruit Street Boston MA 2114 USA
| | - Yong Chen
- Department of Radiation Oncology; University of Oklahoma Health Sciences Center; Oklahoma city OK 73104 USA
| | - Liangzhong Xiang
- School of Electrical and Computer Engineering; The University of Oklahoma; Norman OK 73019 USA
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Vedantham S, Karellas A. Emerging Breast Imaging Technologies on the Horizon. Semin Ultrasound CT MR 2018; 39:114-121. [PMID: 29317033 DOI: 10.1053/j.sult.2017.09.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Early detection of breast cancers by mammography in conjunction with adjuvant therapy has contributed to reduction in breast cancer mortality. Mammography remains the "gold-standard" for breast cancer screening but is limited by tissue superposition. Digital breast tomosynthesis and more recently, dedicated breast computed tomography have been developed to alleviate the tissue superposition problem. However, all of these modalities rely upon x-ray attenuation contrast to provide anatomical images, and there are ongoing efforts to develop and clinically translate alternative modalities. These emerging modalities could provide for new contrast mechanisms and may potentially improve lesion detection and diagnosis. In this article, several of these emerging modalities are discussed with a focus on technologies that have advanced to the stage of in vivo clinical evaluation.
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Affiliation(s)
- Srinivasan Vedantham
- Department of Medical Imaging, University of Arizona College of Medicine, Banner University Medical Center, Tucson, AZ.
| | - Andrew Karellas
- Department of Medical Imaging, University of Arizona College of Medicine, Banner University Medical Center, Tucson, AZ
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35
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Patch SK, Hoff DE, Webb TB, Sobotka LG, Zhao T. Two-stage ionoacoustic range verification leveraging Monte Carlo and acoustic simulations to stably account for tissue inhomogeneity and accelerator-specific time structure - A simulation study. Med Phys 2017; 45:783-793. [DOI: 10.1002/mp.12681] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Revised: 10/06/2017] [Accepted: 10/31/2017] [Indexed: 11/06/2022] Open
Affiliation(s)
- Sarah K. Patch
- Department of Physics; University of Wisconsin-Milwaukee; Milwaukee WI USA
| | - Daniel E.M. Hoff
- Departments of Chemistry and Physics; Washington University; St. Louis MO USA
| | - Tyler B. Webb
- Departments of Chemistry and Physics; Washington University; St. Louis MO USA
| | - Lee G. Sobotka
- Departments of Chemistry and Physics; Washington University; St. Louis MO USA
| | - Tianyu Zhao
- Department of Radiation Oncology; Washington University; St. Louis MO USA
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Hickling S, Lei H, Hobson M, Léger P, Wang X, El Naqa I. Experimental evaluation of x-ray acoustic computed tomography for radiotherapy dosimetry applications. Med Phys 2017; 44:608-617. [PMID: 28121381 DOI: 10.1002/mp.12039] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 11/25/2016] [Accepted: 11/29/2016] [Indexed: 12/31/2022] Open
Abstract
PURPOSE The aim of this work was to experimentally demonstrate the feasibility of x-ray acoustic computed tomography (XACT) as a dosimetry tool in a clinical radiotherapy environment. METHODS The acoustic waves induced following a single pulse of linear accelerator irradiation in a water tank were detected with an immersion ultrasound transducer. By rotating the collimator and keeping the transducer stationary, acoustic signals at varying angles surrounding the field were detected and reconstructed to form an XACT image. Simulated XACT images were obtained using a previously developed simulation workflow. Profiles extracted from experimental and simulated XACT images were compared to profiles measured with an ion chamber. A variety of radiation field sizes and shapes were investigated. RESULTS XACT images resembling the geometry of the delivered radiation field were obtained for fields ranging from simple squares to more complex shapes. When comparing profiles extracted from simulated and experimental XACT images of a 4 cm × 4 cm field, 97% of points were found to pass a 3%/3 mm gamma test. Agreement between simulated and experimental XACT images worsened when comparing fields with fine details. Profiles extracted from experimental XACT images were compared to profiles obtained through clinical ion chamber measurements, confirming that the intensity of XACT images is related to deposited radiation dose. Seventy-seven percent of the points in a profile extracted from an experimental XACT image of a 4 cm × 4 cm field passed a 7%/4 mm gamma test when compared to an ion chamber measured profile. In a complicated puzzle-piece shaped field, 86% of the points in an XACT extracted profile passed a 7%/4 mm gamma test. CONCLUSIONS XACT images with intensity related to the spatial distribution of deposited dose in a water tank were formed for a variety of field sizes and shapes. XACT has the potential to be a useful tool for absolute, relative and in vivo dosimetry.
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Affiliation(s)
- Susannah Hickling
- Department of Physics and Medical Physics Unit, McGill University, Cedars Cancer Centre, Montreal, QC, Canada, H4A 3J1
| | - Hao Lei
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Maritza Hobson
- Medical Physics Unit, McGill University Health Centre, Cedars Cancer Centre, Montreal, QC, H4A 3J1, Canada
| | - Pierre Léger
- Medical Physics Unit, McGill University Health Centre, Cedars Cancer Centre, Montreal, QC, H4A 3J1, Canada
| | - Xueding Wang
- Departments of Radiology and Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109-0600, USA
| | - Issam El Naqa
- Department of Radiation Oncology, University of Michigan, Ann Arbor, MI, 48103-4943, USA
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Ahmad M, Xiang L, Yousefi S, Xing L. Theoretical detection threshold of the proton-acoustic range verification technique. Med Phys 2016; 42:5735-44. [PMID: 26429247 DOI: 10.1118/1.4929939] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Range verification in proton therapy using the proton-acoustic signal induced in the Bragg peak was investigated for typical clinical scenarios. The signal generation and detection processes were simulated in order to determine the signal-to-noise limits. METHODS An analytical model was used to calculate the dose distribution and local pressure rise (per proton) for beams of different energy (100 and 160 MeV) and spot widths (1, 5, and 10 mm) in a water phantom. In this method, the acoustic waves propagating from the Bragg peak were generated by the general 3D pressure wave equation implemented using a finite element method. Various beam pulse widths (0.1-10 μs) were simulated by convolving the acoustic waves with Gaussian kernels. A realistic PZT ultrasound transducer (5 cm diameter) was simulated with a Butterworth bandpass filter with consideration of random noise based on a model of thermal noise in the transducer. The signal-to-noise ratio on a per-proton basis was calculated, determining the minimum number of protons required to generate a detectable pulse. The maximum spatial resolution of the proton-acoustic imaging modality was also estimated from the signal spectrum. RESULTS The calculated noise in the transducer was 12-28 mPa, depending on the transducer central frequency (70-380 kHz). The minimum number of protons detectable by the technique was on the order of 3-30 × 10(6) per pulse, with 30-800 mGy dose per pulse at the Bragg peak. Wider pulses produced signal with lower acoustic frequencies, with 10 μs pulses producing signals with frequency less than 100 kHz. CONCLUSIONS The proton-acoustic process was simulated using a realistic model and the minimal detection limit was established for proton-acoustic range validation. These limits correspond to a best case scenario with a single large detector with no losses and detector thermal noise as the sensitivity limiting factor. Our study indicated practical proton-acoustic range verification may be feasible with approximately 5 × 10(6) protons/pulse and beam current.
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Affiliation(s)
- Moiz Ahmad
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305-5847
| | - Liangzhong Xiang
- Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, Oklahoma 73019-1101
| | - Siavash Yousefi
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305-5847
| | - Lei Xing
- Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305-5847
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Xiang L, Tang S, Ahmad M, Xing L. High Resolution X-ray-Induced Acoustic Tomography. Sci Rep 2016; 6:26118. [PMID: 27189746 PMCID: PMC4870558 DOI: 10.1038/srep26118] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 04/27/2016] [Indexed: 11/09/2022] Open
Abstract
Absorption based CT imaging has been an invaluable tool in medical diagnosis, biology, and materials science. However, CT requires a large set of projection data and high radiation dose to achieve superior image quality. In this letter, we report a new imaging modality, X-ray Induced Acoustic Tomography (XACT), which takes advantages of high sensitivity to X-ray absorption and high ultrasonic resolution in a single modality. A single projection X-ray exposure is sufficient to generate acoustic signals in 3D space because the X-ray generated acoustic waves are of a spherical nature and propagate in all directions from their point of generation. We demonstrate the successful reconstruction of gold fiducial markers with a spatial resolution of about 350 μm. XACT reveals a new imaging mechanism and provides uncharted opportunities for structural determination with X-ray.
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Affiliation(s)
- Liangzhong Xiang
- Department of Radiation Oncology, School of Medicine, Stanford University, Stanford, CA 94305, USA.,Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Shanshan Tang
- Center for Bioengineering and School of Electrical and Computer Engineering, University of Oklahoma, Norman, OK 73019, USA
| | - Moiz Ahmad
- Department of Radiation Oncology, School of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Lei Xing
- Department of Radiation Oncology, School of Medicine, Stanford University, Stanford, CA 94305, USA
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Hickling S, Leger P, El Naqa I. On the Detectability of Acoustic Waves Induced Following Irradiation by a Radiotherapy Linear Accelerator. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2016; 63:683-690. [PMID: 26886983 DOI: 10.1109/tuffc.2016.2528960] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Irradiating an object with a megavoltage photon beam generated by a clinical radiotherapy linear accelerator (linac) induces acoustic waves through the photoacoustic effect. The detection and characterization of such acoustic waves has potential applications in radiation therapy dosimetry. The purpose of this work was to gain insight into the properties of such acoustic waves by simulating and experimentally detecting them in a well-defined system consisting of a metal block suspended in a water tank. A novel simulation workflow was developed by combining radiotherapy Monte Carlo and acoustic wave transport simulation techniques. Different set-up parameters such as photon beam energy, metal block depth, metal block width, and metal block material were varied, and the simulated and experimental acoustic waveforms showed the same relative amplitude trends and frequency variations for such setup changes. The simulation platform developed in this work can easily be extended to other irradiation situations, and will be an invaluable tool for developing a radiotherapy dosimetry system based on the detection of the acoustic waves induced following linear accelerator irradiation.
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40
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Xia J, Kim C, Lovell JF. Opportunities for Photoacoustic-Guided Drug Delivery. Curr Drug Targets 2016; 16:571-81. [PMID: 26148989 DOI: 10.2174/1389450116666150707100328] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Revised: 09/11/2014] [Accepted: 09/11/2014] [Indexed: 01/23/2023]
Abstract
Photoacoustic imaging (PAI) is rapidly becoming established as a viable imaging modality for small animal research, with promise of near-future human clinical translation. In this review, we discuss emerging prospects for photoacoustic-guided drug delivery. PAI presents opportunities for applications related to drug delivery, mainly with respect to either monitoring drug effects or monitoring drugs themselves. PAI is well-suited for imaging disease pathology and treatment response. Alternatively, PAI can be used to directly monitor the accumulation of various light-absorbing contrast agents or carriers with theranostic properties.
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Affiliation(s)
| | | | - Jonathan F Lovell
- Department of Biomedical Engineering, University at Buffalo, Buffalo, USA.
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41
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O'Shea T, Bamber J, Fontanarosa D, van der Meer S, Verhaegen F, Harris E. Review of ultrasound image guidance in external beam radiotherapy part II: intra-fraction motion management and novel applications. Phys Med Biol 2016; 61:R90-137. [PMID: 27002558 DOI: 10.1088/0031-9155/61/8/r90] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Imaging has become an essential tool in modern radiotherapy (RT), being used to plan dose delivery prior to treatment and verify target position before and during treatment. Ultrasound (US) imaging is cost-effective in providing excellent contrast at high resolution for depicting soft tissue targets apart from those shielded by the lungs or cranium. As a result, it is increasingly used in RT setup verification for the measurement of inter-fraction motion, the subject of Part I of this review (Fontanarosa et al 2015 Phys. Med. Biol. 60 R77-114). The combination of rapid imaging and zero ionising radiation dose makes US highly suitable for estimating intra-fraction motion. The current paper (Part II of the review) covers this topic. The basic technology for US motion estimation, and its current clinical application to the prostate, is described here, along with recent developments in robust motion-estimation algorithms, and three dimensional (3D) imaging. Together, these are likely to drive an increase in the number of future clinical studies and the range of cancer sites in which US motion management is applied. Also reviewed are selections of existing and proposed novel applications of US imaging to RT. These are driven by exciting developments in structural, functional and molecular US imaging and analytical techniques such as backscatter tissue analysis, elastography, photoacoustography, contrast-specific imaging, dynamic contrast analysis, microvascular and super-resolution imaging, and targeted microbubbles. Such techniques show promise for predicting and measuring the outcome of RT, quantifying normal tissue toxicity, improving tumour definition and defining a biological target volume that describes radiation sensitive regions of the tumour. US offers easy, low cost and efficient integration of these techniques into the RT workflow. US contrast technology also has potential to be used actively to assist RT by manipulating the tumour cell environment and by improving the delivery of radiosensitising agents. Finally, US imaging offers various ways to measure dose in 3D. If technical problems can be overcome, these hold potential for wide-dissemination of cost-effective pre-treatment dose verification and in vivo dose monitoring methods. It is concluded that US imaging could eventually contribute to all aspects of the RT workflow.
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Affiliation(s)
- Tuathan O'Shea
- Joint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton, London SM2 5NG, UK
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Fontanarosa D, van der Meer S, Bamber J, Harris E, O'Shea T, Verhaegen F. Review of ultrasound image guidance in external beam radiotherapy: I. Treatment planning and inter-fraction motion management. Phys Med Biol 2015; 60:R77-114. [PMID: 25592664 DOI: 10.1088/0031-9155/60/3/r77] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
In modern radiotherapy, verification of the treatment to ensure the target receives the prescribed dose and normal tissues are optimally spared has become essential. Several forms of image guidance are available for this purpose. The most commonly used forms of image guidance are based on kilovolt or megavolt x-ray imaging. Image guidance can also be performed with non-harmful ultrasound (US) waves. This increasingly used technique has the potential to offer both anatomical and functional information.This review presents an overview of the historical and current use of two-dimensional and three-dimensional US imaging for treatment verification in radiotherapy. The US technology and the implementation in the radiotherapy workflow are described. The use of US guidance in the treatment planning process is discussed. The role of US technology in inter-fraction motion monitoring and management is explained, and clinical studies of applications in areas such as the pelvis, abdomen and breast are reviewed. A companion review paper (O'Shea et al 2015 Phys. Med. Biol. submitted) will extensively discuss the use of US imaging for intra-fraction motion quantification and novel applications of US technology to RT.
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Affiliation(s)
- Davide Fontanarosa
- Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC), Maastricht 6201 BN, the Netherlands. Oncology Solutions Department, Philips Research, High Tech Campus 34, Eindhoven 5656 AE, the Netherlands
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Li C, Di K, Bec J, Cherry SR. X-ray luminescence optical tomography imaging: experimental studies. OPTICS LETTERS 2013; 38:2339-41. [PMID: 23811921 PMCID: PMC5204368 DOI: 10.1364/ol.38.002339] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We present a hybrid imaging modality, x-ray luminescence optical tomography (XLOT), in which collimated x-ray beams are used to excite phosphor-based contrast agents. Images are reconstructed from the optical signals, using the known x-ray beam location and spatial extent as priors. We demonstrate XLOT using phantom experiments with deep targets and show that the reconstructed signal varies by <12% when the depth changes from 4.2 to 7.7 mm. For simple source distributions, we find as few as two orthogonal projection measurements are sufficient for XLOT reconstruction.
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Affiliation(s)
- Changqing Li
- School of Engineering, University of California, Merced, California 95343, USA.
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