1
|
Nouizi F, Kwong TC, Turong B, Nikkhah D, Sampathkumaran U, Gulsen G. Fast ICCD-based temperature modulated fluorescence tomography. APPLIED OPTICS 2023; 62:7420-7430. [PMID: 37855510 PMCID: PMC11396546 DOI: 10.1364/ao.499281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 09/06/2023] [Indexed: 10/20/2023]
Abstract
Fluorescence tomography (FT) has become a powerful preclinical imaging modality with a great potential for several clinical applications. Although it has superior sensitivity and utilizes low-cost instrumentation, the highly scattering nature of bio-tissue makes FT in thick samples challenging, resulting in poor resolution and low quantitative accuracy. To overcome the limitations of FT, we previously introduced a novel method, termed temperature modulated fluorescence tomography (TMFT), which is based on two key elements: (1) temperature-sensitive fluorescent agents (ThermoDots) and (2) high-intensity focused ultrasound (HIFU). The fluorescence emission of ThermoDots increases up to hundredfold with only several degree temperature elevation. The exceptional and reversible response of these ThermoDots enables their modulation, which effectively allows their localization using the HIFU. Their localization is then used as functional a priori during the FT image reconstruction process to resolve their distribution with higher spatial resolution. The last version of the TMFT system was based on a cooled CCD camera utilizing a step-and-shoot mode, which necessitated long total imaging time only for a small selected region of interest (ROI). In this paper, we present the latest version of our TMFT technology, which uses a much faster continuous HIFU scanning mode based on an intensified CCD (ICCD) camera. This new, to the best of our knowledge, version can capture the whole field-of-view (FOV) of 50×30m m 2 at once and reduces the total imaging time down to 30 min, while preserving the same high resolution (∼1.3m m) and superior quantitative accuracy (<7% error) as the previous versions. Therefore, this new method is an important step toward utilization of TMFT for preclinical imaging.
Collapse
|
2
|
Nouizi F, Erkol H, Nikkhah D, Kwong TC, Gulsen G. Development of a preclinical CCD-based temperature modulated fluorescence tomography platform. BIOMEDICAL OPTICS EXPRESS 2022; 13:5740-5752. [PMID: 36733748 PMCID: PMC9872903 DOI: 10.1364/boe.470723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 09/25/2022] [Accepted: 09/26/2022] [Indexed: 05/11/2023]
Abstract
In preclinical research, fluorescence molecular tomography (FMT) is the most sensitive imaging modality to interrogate whole-body and provide 3D distribution of fluorescent contract agents. Despite its superior sensitivity, its mediocre spatial-resolution has been the main barrier to its clinical translation. This limitation is mainly due to the high scattering of optical photons in biological tissue together with the limited boundary measurements that lead to an undetermined and ill-posed inverse problem. To overcome the limitations of FMT, we previously introduced a novel method termed, Temperature Modulated Fluorescence Tomography (TMFT). TMFT utilizes thermos-sensitive fluorescent agents (ThermoDots) as a key component and localizes them with high-intensity focused ultrasound (HIFU). Scanning the focused HIFU beam having a diameter Ø = 1.3 mm across the tissue while monitoring the variation in the measured fluorescence signals reveals the position of the ThermoDots with high spatial accuracy. We have formerly built a prototype TMFT system that uses optical fibers for detection. In this paper, we present an upgraded version using a CCD camera-based detection that enables non-contact imaging. In this version, the animal under investigation is placed on an ultrasound transparent membrane, which eliminates the need for its immersion in optical matching fluids that were required by the fiber-based system. This CCD-based system will pave the way for convenient and wide-spread use of TMFT in preclinical research. Its performance validation on phantom studies demonstrates that high spatial-resolution (∼1.3 mm) and quantitative accuracy in recovered fluorophore concentration (<3% error) can be achieved.
Collapse
Affiliation(s)
- Farouk Nouizi
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, CA 92697, USA
- Chao Family Comprehensive Cancer Center, University of California Irvine, CA 92697, USA
| | - Hakan Erkol
- Department of Physics, Bogazici University, Bebek, 34342, Istanbul, Turkey
| | - Deniz Nikkhah
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, CA 92697, USA
| | - Tiffany C. Kwong
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, CA 92697, USA
| | - Gultekin Gulsen
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, CA 92697, USA
- Chao Family Comprehensive Cancer Center, University of California Irvine, CA 92697, USA
| |
Collapse
|
3
|
Nouizi F, Brooks J, Zuro DM, Hui SK, Gulsen G. Development of a theranostic preclinical fluorescence molecular tomography/cone beam CT-guided irradiator platform. BIOMEDICAL OPTICS EXPRESS 2022; 13:6100-6112. [PMID: 36733750 PMCID: PMC9872876 DOI: 10.1364/boe.469559] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 09/21/2022] [Accepted: 09/22/2022] [Indexed: 05/11/2023]
Abstract
Image-guided small animal radiation research platforms allow more precise radiation treatment. Commercially available small animal X-ray irradiators are often equipped with a CT/cone-beam CT (CBCT) component for target guidance. Besides having poor soft-tissue contrast, CBCT unfortunately cannot provide molecular information due to its low sensitivity. Hence, there are extensive efforts to incorporate a molecular imaging component besides CBCT on these radiation therapy platforms. As an extension of these efforts, here we present a theranostic fluorescence tomography/CBCT-guided irradiator platform that provides both anatomical and molecular guidance, which can overcome the limitations of stand-alone CBCT. The performance of our hybrid system is validated using both tissue-like phantoms and mice ex vivo. Both studies show that fluorescence tomography can provide much more accurate quantitative results when CBCT-derived structural information is used to constrain the inverse problem. The error in the recovered fluorescence absorbance reduces nearly 10-fold for all cases, from approximately 60% down to 6%. This is very significant since high quantitative accuracy in molecular information is crucial to the correct assessment of the changes in tumor microenvironment related to radiation therapy.
Collapse
Affiliation(s)
- Farouk Nouizi
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, CA 92697, USA
- Chao Family Comprehensive Cancer Center, University of California Irvine, CA 92697, USA
| | - Jamison Brooks
- Department of Radiation Oncology, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA 91010, USA
| | - Darren M. Zuro
- Department of Radiation Oncology, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA 91010, USA
| | - Susanta K. Hui
- Department of Radiation Oncology, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA 91010, USA
| | - Gultekin Gulsen
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, CA 92697, USA
- Chao Family Comprehensive Cancer Center, University of California Irvine, CA 92697, USA
| |
Collapse
|
4
|
Algarawi M, Erkol H, Luk A, Ha S, Ünlü MB, Gulsen G, Nouizi F. Resolving tissue chromophore concentration at MRI resolution using multi-wavelength photo-magnetic imaging. BIOMEDICAL OPTICS EXPRESS 2020; 11:4244-4254. [PMID: 32923039 PMCID: PMC7449711 DOI: 10.1364/boe.397538] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/24/2020] [Accepted: 06/30/2020] [Indexed: 06/11/2023]
Abstract
Photo-magnetic imaging (PMI) is an emerging optical imaging modality that showed great performance on providing absorption maps with high resolution and quantitative accuracy. As a multi-modality technology, PMI warms up the imaged object using a near infrared laser while temperature variation is measured using magnetic resonance imaging. By probing tissue at multiple wavelengths, concentration of the main tissue chromophores such as oxy- and deoxy-hemoglobin, lipid, and water are obtained then used to derive functional parameters such as total hemoglobin concentration and relative oxygen saturation. In this paper, we present a multi-wavelength PMI system that was custom-built to host five different laser wavelengths. After recovering the high-resolution absorption maps, a least-squared minimization process was used to resolve the different chromophore concentration. The performance of the system was experimentally tested on a phantom with two different dyes. Their concentrations were successfully assessed with high spatial resolution and average accuracy of nearly 80%.
Collapse
Affiliation(s)
- Maha Algarawi
- Center for Functional Onco-Imaging, University of California Irvine, CA 92697, USA
- Department of Physics and Astronomy, University of California Irvine, CA 92697, USA
| | - Hakan Erkol
- Department of Physics, Bogazici University, Istanbul, Turkey
| | - Alex Luk
- Center for Functional Onco-Imaging, University of California Irvine, CA 92697, USA
| | | | - Mehmet B. Ünlü
- Department of Physics, Bogazici University, Istanbul, Turkey
| | - Gultekin Gulsen
- Center for Functional Onco-Imaging, University of California Irvine, CA 92697, USA
- Department of Physics and Astronomy, University of California Irvine, CA 92697, USA
- Department of Radiological Sciences, University of California Irvine, CA 92697, USA
| | - Farouk Nouizi
- Center for Functional Onco-Imaging, University of California Irvine, CA 92697, USA
- Department of Radiological Sciences, University of California Irvine, CA 92697, USA
| |
Collapse
|
5
|
Lo PA, Su SP, Chiang HK. Small-animal 360-deg fluorescence diffuse optical tomography using structural prior information from ultrasound imaging. JOURNAL OF BIOMEDICAL OPTICS 2020; 25:1-11. [PMID: 32129028 PMCID: PMC7052526 DOI: 10.1117/1.jbo.25.3.036001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 01/23/2020] [Indexed: 06/10/2023]
Abstract
We demonstrate dual modality of free-space fluorescence diffuse optical tomography (FDOT) and handheld ultrasound (US) imaging to reveal both functional and structural information in small animals. FDOT is a noninvasive method for examining the fluorophore inside an object from the light distribution of the surface. In FDOT, a 660-nm continuous wave diode laser was used as an excitation source and an electron-multiplying charge-coupled device (EMCCD) was used for fluorescence data acquisition. Both the laser and EMCCD were mounted on a 360-deg rotation gantry for the transmission optical data collection. The structural information is obtained from a 6- to 17-MHz handheld US linear transducer by single-side access and conducts in the reconstruction as soft priors. The rotation ranges from 0 deg to 360 deg; different rotation degrees, object positions, and parameters were determined for comparison. Both phantom and tissue phantom results demonstrate that fluorophore distribution can be recovered accurately and quantitatively using this imaging system. Finally, an animal study confirms that the system can extract a dual-modality image, validating its feasibility for further in vivo experiments. In all experiments, the error and standard deviation decrease as the rotation degree is increased and the error was reduced to 10% when the rotation degree was increased over 135 deg.
Collapse
Affiliation(s)
- Pei-An Lo
- National Yang-Ming University, Institute of Biomedical Engineering, Taipei, Taiwan
| | - Shih-Po Su
- National Yang-Ming University, Institute of Biomedical Engineering, Taipei, Taiwan
| | - Huihua Kenny Chiang
- National Yang-Ming University, Institute of Biomedical Engineering, Taipei, Taiwan
| |
Collapse
|
6
|
Nouizi F, Brooks J, Zuro DM, Madabushi SS, Moreira D, Kortylewski M, Froelich J, Su LM, Gulsen G, Hui SK. Automated in vivo Assessment of Vascular Response to Radiation using a Hybrid Theranostic X-ray Irradiator/Fluorescence Molecular Imaging System. IEEE ACCESS : PRACTICAL INNOVATIONS, OPEN SOLUTIONS 2020; 8:93663-93670. [PMID: 32542176 PMCID: PMC7295127 DOI: 10.1109/access.2020.2994943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Hypofractionated stereotactic body radiotherapy treatments (SBRT) have demonstrated impressive results for the treatment of a variety of solid tumors. The role of tumor supporting vasculature damage in treatment outcome for SBRT has been intensely debated and studied. Fast, non-invasive, longitudinal assessments of tumor vasculature would allow for thorough investigations of vascular changes correlated with SBRT treatment response. In this paper, we present a novel theranostic system which incorporates a fluorescence molecular imager into a commercial, preclinical, microCT-guided, irradiator and was designed to quantify tumor vascular response (TVR) to targeted radiotherapy. This system overcomes the limitations of single-timepoint imaging modalities by longitudinally assessing spatiotemporal differences in intravenously-injected ICG kinetics in tumors before and after high-dose radiation. Changes in ICG kinetics were rapidly quantified by principle component (PC) analysis before and two days after 10 Gy targeted tumor irradiation. A classifier algorithm based on PC data clustering identified pixels with TVR. Results show that two days after treatment, a significant delay in ICG clearance as measured by exponential decay (40.5±16.1% P=0.0405 Paired t-test n=4) was observed. Changes in the mean normalized first and second PC feature pixel values (PC1 & PC2) were found (P=0.0559, 0.0432 paired t-test), suggesting PC based analysis accurately detects changes in ICG kinetics. The PC based classification algorithm yielded spatially-resolved TVR maps. Our first-of-its-kind theranostic system, allowing automated assessment of TVR to SBRT, will be used to better understand the role of tumor perfusion in metastasis and local control.
Collapse
Affiliation(s)
- Farouk Nouizi
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, Irvine, CA 92697 USA
| | - Jamison Brooks
- Department of Radiation Oncology, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA 91010 USA
- Department of Radiation Oncology, University of Minnesota, Minneapolis, MN 55455 USA
| | - Darren M. Zuro
- Department of Radiation Oncology, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA 91010 USA
- Department of Radiation Oncology, University of Minnesota, Minneapolis, MN 55455 USA
| | - Srideshikan Sargur Madabushi
- Department of Radiation Oncology, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA 91010 USA
| | - Dayson Moreira
- Department of Immuno-Oncology, Beckman Research Institute at City of Hope, Duarte, CA 91010 USA
| | - Marcin Kortylewski
- Department of Immuno-Oncology, Beckman Research Institute at City of Hope, Duarte, CA 91010 USA
| | - Jerry Froelich
- Department of Radiology, University of Minnesota, Minneapolis, MN
| | - Lydia M. Su
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, Irvine, CA 92697 USA
| | - Gultekin Gulsen
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California Irvine, Irvine, CA 92697 USA
| | - Susanta K. Hui
- Department of Radiation Oncology, Beckman Research Institute, City of Hope National Medical Center, Duarte, CA 91010 USA
| |
Collapse
|
7
|
Daly MJ, Chan H, Muhanna N, Akens MK, Wilson BC, Irish JC, Jaffray DA. Intraoperative cone-beam CT spatial priors for diffuse optical fluorescence tomography. ACTA ACUST UNITED AC 2019; 64:215007. [DOI: 10.1088/1361-6560/ab4917] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
8
|
Nouizi F, Kwong TC, Ruiz J, Cho J, Chan YW, Ikemura K, Erkol H, Sampathkumaran U, Gulsen G. A thermo-sensitive fluorescent agent based method for excitation light leakage rejection for fluorescence molecular tomography. Phys Med Biol 2019; 64:035007. [PMID: 30561380 DOI: 10.1088/1361-6560/aaf96d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Fluorescence molecular tomography (FMT) is widely used in preclinical oncology research. FMT is the only imaging technique able to provide 3D distribution of fluorescent probes within thick highly scattering media. However, its integration into clinical medicine has been hampered by its low spatial resolution caused by the undetermined and ill-posed nature of its reconstruction algorithm. Another major factor degrading the quality of FMT images is the large backscattered excitation light component leaking through the rejection filters and coinciding with the weak fluorescent signal arising from a low tissue fluorescence concentration. In this paper, we present a new method based on the use of a novel thermo-sensitive fluorescence probe. In fact, the excitation light leakage is accurately estimated from a set of measurements performed at different temperatures and then is corrected for in the tomographic data. The obtained results show a considerable improvement in both spatial resolution and quantitative accuracy of FMT images due to the proper correction of fluorescent signals.
Collapse
Affiliation(s)
- Farouk Nouizi
- Department of Radiological Sciences, Tu and Yuen Center for Functional Onco-Imaging, University of California, Irvine, CA 92697, United States of America
| | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Baikejiang R, Zhao Y, Fite BZ, Ferrara KW, Li C. Anatomical image-guided fluorescence molecular tomography reconstruction using kernel method. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:55001. [PMID: 28464120 PMCID: PMC5629124 DOI: 10.1117/1.jbo.22.5.055001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 04/10/2017] [Indexed: 05/20/2023]
Abstract
Fluorescence molecular tomography (FMT) is an important in vivo imaging modality to visualize physiological and pathological processes in small animals. However, FMT reconstruction is ill-posed and ill-conditioned due to strong optical scattering in deep tissues, which results in poor spatial resolution. It is well known that FMT image quality can be improved substantially by applying the structural guidance in the FMT reconstruction. An approach to introducing anatomical information into the FMT reconstruction is presented using the kernel method. In contrast to conventional methods that incorporate anatomical information with a Laplacian-type regularization matrix, the proposed method introduces the anatomical guidance into the projection model of FMT. The primary advantage of the proposed method is that it does not require segmentation of targets in the anatomical images. Numerical simulations and phantom experiments have been performed to demonstrate the proposed approach’s feasibility. Numerical simulation results indicate that the proposed kernel method can separate two FMT targets with an edge-to-edge distance of 1 mm and is robust to false-positive guidance and inhomogeneity in the anatomical image. For the phantom experiments with two FMT targets, the kernel method has reconstructed both targets successfully, which further validates the proposed kernel method.
Collapse
Affiliation(s)
- Reheman Baikejiang
- University of California, Merced, School of Engineering, Merced, California, United States
| | - Yue Zhao
- University of California, Merced, School of Engineering, Merced, California, United States
| | - Brett Z. Fite
- University of California, Davis, Department of Biomedical Engineering, Davis, California, United States
| | - Katherine W. Ferrara
- University of California, Davis, Department of Biomedical Engineering, Davis, California, United States
| | - Changqing Li
- University of California, Merced, School of Engineering, Merced, California, United States
- Address all correspondence to: Changqing Li, E-mail:
| |
Collapse
|
10
|
KWONG TIFFANYC, NOUIZI FAROUK, LIN YUTING, CHO JAEDU, ZHU YUE, SAMPATHKUMARAN UMA, GULSEN GULTEKIN. Experimental evaluation of the resolution and quantitative accuracy of temperature-modulated fluorescence tomography. APPLIED OPTICS 2017; 56:521-529. [PMID: 28157909 PMCID: PMC6855591 DOI: 10.1364/ao.56.000521] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Previously, we reported on the spatial resolution and quantitative accuracy of temperature-modulated fluorescence tomography (TM-FT) using simulation studies. TM-FT is a novel fully integrated multimodality imaging technique that combines fluorescence diffuse optical tomography (FT) with focused ultrasound. Utilizing unique thermo-reversible fluorescent nanocapsules (ThermoDots), TM-FT provides high-resolution cross-sectional fluorescence images in thick tissue (up to 6 cm). Focused ultrasound and temperature-sensitive ThermoDots are combined to provide accurate localization of these fluorescent probes and functional a priori information to constrain the conventional FT reconstruction algorithm. Our previous simulation studies evaluated the performance of TM-FT using synthetic phantoms with multiple fluorescence targets of various sizes located at different depths. In this follow-up work, we perform experimental studies to evaluate the performance of this hybrid imaging system, in particular, the effect of size, depth, and concentration of the fluorescence target. While FT alone is unable to accurately locate and resolve the fluorophore target in many cases, TM-FT is able to resolve the size and concentration of the ThermoDots within a thick turbid medium with high accuracy for all cases. The maximum error in the recovered ThermoDots concentration and target sizes with TM-FT are 12% and 25%, respectively.
Collapse
Affiliation(s)
- TIFFANY C. KWONG
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
| | - FAROUK NOUIZI
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
| | - YUTING LIN
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02144, USA
| | - JAEDU CHO
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
| | - YUE ZHU
- InnoSense LLC, Torrance, California 90505, USA
| | | | - GULTEKIN GULSEN
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
| |
Collapse
|
11
|
Wan W, Wang Y, Qi J, Liu L, Ma W, Li J, Zhang L, Zhou Z, Zhao H, Gao F. Region-based diffuse optical tomography with registered atlas: in vivo acquisition of mouse optical properties. BIOMEDICAL OPTICS EXPRESS 2016; 7:5066-5080. [PMID: 28018725 PMCID: PMC5175552 DOI: 10.1364/boe.7.005066] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 10/20/2016] [Accepted: 11/09/2016] [Indexed: 05/14/2023]
Abstract
The reconstruction quality in the model-based optical tomography modalities can greatly benefit from a priori information of accurate tissue optical properties, which are difficult to be obtained in vivo with a conventional diffuse optical tomography (DOT) system alone. One of the solutions is to apply a priori anatomical structures obtained with anatomical imaging systems such as X-ray computed tomography (XCT) to constrain the reconstruction process of DOT. However, since X-ray offers low soft-tissue contrast, segmentation of abdominal organs from sole XCT images can be problematic. In order to overcome the challenges, the current study proposes a novel method of recovering a priori organ-oriented tissue optical properties, where anatomical structures of an in vivo mouse are approximately obtained by registering a standard anatomical atlas, i.e., the Digimouse, to the target XCT volume with the non-rigid image registration, and, in turn, employed to guide DOT for extracting the optical properties of inner organs. Simulative investigations have validated the methodological availability of such atlas-registration-based DOT strategy in revealing both a priori anatomical structures and optical properties. Further experiments have demonstrated the feasibility of the proposed method for acquiring the organ-oriented tissue optical properties of in vivo mice, making it as an efficient way of the reconstruction enhancement.
Collapse
Affiliation(s)
- Wenbo Wan
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Yihan Wang
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Jin Qi
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Cancer Institute and Hospital, Tianjin Medical University, Tianjin 300060, China
| | - Lingling Liu
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
| | - Wenjuan Ma
- Cancer Institute and Hospital, Tianjin Medical University, Tianjin 300060, China
| | - Jiao Li
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
| | - Limin Zhang
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
| | - Zhongxing Zhou
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
| | - Huijuan Zhao
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
| | - Feng Gao
- College of Precision Instrument and Optoelectronics Engineering, Tianjin University, Tianjin 300072, China
- Tianjin Key Laboratory of Biomedical Detecting Techniques and Instruments, Tianjin 300072, China
| |
Collapse
|
12
|
Reconstruction for Limited-Projection Fluorescence Molecular Tomography Based on a Double-Mesh Strategy. BIOMED RESEARCH INTERNATIONAL 2016; 2016:5682851. [PMID: 27830148 PMCID: PMC5086542 DOI: 10.1155/2016/5682851] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 08/25/2016] [Accepted: 09/20/2016] [Indexed: 11/17/2022]
Abstract
Limited-projection fluorescence molecular tomography (FMT) has short data acquisition time that allows fast resolving of the three-dimensional visualization of fluorophore within small animal in vivo. However, limited-projection FMT reconstruction suffers from severe ill-posedness because only limited projections are used for reconstruction. To alleviate the ill-posedness, a feasible region extraction strategy based on a double mesh is presented for limited-projection FMT. First, an initial result is rapidly recovered using a coarse discretization mesh. Then, the reconstructed fluorophore area in the initial result is selected as a feasible region to guide the reconstruction using a fine discretization mesh. Simulation experiments on a digital mouse and small animal experiment in vivo are performed to validate the proposed strategy. It demonstrates that the presented strategy provides a good distribution of fluorophore with limited projections of fluorescence measurements. Hence, it is suitable for reconstruction of limited-projection FMT.
Collapse
|
13
|
Lian L, Deng Y, Xie W, Xu G, Yang X, Zhang Z, Luo Q. High-dynamic-range fluorescence molecular tomography for imaging of fluorescent targets with large concentration differences. OPTICS EXPRESS 2016; 24:19920-33. [PMID: 27557267 DOI: 10.1364/oe.24.019920] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
When CCD-based free-space fluorescence molecular tomography (FMT) is used for imaging of fluorescent targets with a large concentration difference, the limited dynamic range of the CCD diminishes the localization and quantitative accuracy of FMT. To overcome this, we present a high-dynamic-range FMT (HDR-FMT) method. Under the multiple-exposure scheme, HDR fluorescence projection images are constructed using the recovered CCD response curve. Image reconstruction is implemented using iterative reweighted L1 regularization which can reduce artifacts by using fewer HDR fluorescence projection images. Phantom and in vivo animal studies indicate that localization of fluorescent targets with a large concentration difference is effectively improved with HDR-FMT and with good quantitative accuracy.
Collapse
|
14
|
Abstract
Diffuse fluorescence tomography (DFT) has been developed to image the spatial distribution of fluorescence-tagged tracers in living tissue. This capability facilitates the recovery of any number of functional parameters, including enzymatic activity, receptor density, blood flow, and gene expression. However, deploying DFT effectively is complex and often requires years of know-how, especially for newer mutlimodal systems that combine DFT with conventional imaging systems. In this chapter, we step through the process of using MRI-DFT imaging of a receptor-targeted tracer in small animals.
Collapse
|
15
|
Zhang X, Zhang J, Luo J. Reconstruction of in vivo fluorophore concentration variation with structural priors and smooth penalty. APPLIED OPTICS 2016; 55:2732-2740. [PMID: 27139679 DOI: 10.1364/ao.55.002732] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Reconstruction of fluorophore concentration variation in fluorescence molecular tomography is expected to reveal the metabolic processes of fluorescent biomarkers in vivo. However, the complicated and strong noise within in vivo data inhibits its applications for in vivo cases. A smooth penalty method is presented in this work to suppress the noise. The method is based on a recursive reconstruction scheme which reconstructs the fluorophore concentration variation rates (FCVRs) of two neighboring frames at the same time within an inner iteration. In addition, the performance of the Laplacian-type regularization incorporating structural priors is investigated. Results of simulations suggest that the smooth penalty method almost has no influence on the reconstructed FCVRs when the target curve is smooth, and results of in vivo experiments on mice indicate that the method is capable of suppressing the noise and achieving smooth time courses of fluorescent yield. Results of both the simulations and in vivo experiments demonstrate that the Laplacian-type regularization can improve the image quality.
Collapse
|
16
|
Lin Y, Nouizi F, Kwong TC, Gulsen G. Simulation-based evaluation of the resolution and quantitative accuracy of temperature-modulated fluorescence tomography. APPLIED OPTICS 2015; 54:7612-21. [PMID: 26368884 PMCID: PMC4896397 DOI: 10.1364/ao.54.007612] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Conventional fluorescence tomography (FT) can recover the distribution of fluorescent agents within a highly scattering medium. However, poor spatial resolution remains its foremost limitation. Previously, we introduced a new fluorescence imaging technique termed "temperature-modulated fluorescence tomography" (TM-FT), which provides high-resolution images of fluorophore distribution. TM-FT is a multimodality technique that combines fluorescence imaging with focused ultrasound to locate thermo-sensitive fluorescence probes using a priori spatial information to drastically improve the resolution of conventional FT. In this paper, we present an extensive simulation study to evaluate the performance of the TM-FT technique on complex phantoms with multiple fluorescent targets of various sizes located at different depths. In addition, the performance of the TM-FT is tested in the presence of background fluorescence. The results obtained using our new method are systematically compared with those obtained with the conventional FT. Overall, TM-FT provides higher resolution and superior quantitative accuracy, making it an ideal candidate for in vivo preclinical and clinical imaging. For example, a 4 mm diameter inclusion positioned in the middle of a synthetic slab geometry phantom (D:40 mm×W:100 mm) is recovered as an elongated object in the conventional FT (x=4.5 mm; y=10.4 mm), while TM-FT recovers it successfully in both directions (x=3.8 mm; y=4.6 mm). As a result, the quantitative accuracy of the TM-FT is superior because it recovers the concentration of the agent with a 22% error, which is in contrast with the 83% error of the conventional FT.
Collapse
Affiliation(s)
- Yuting Lin
- Tu and Yuen Center for Functional Onco Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts 02114, USA
| | - Farouk Nouizi
- Tu and Yuen Center for Functional Onco Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
| | - Tiffany C. Kwong
- Tu and Yuen Center for Functional Onco Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
| | - Gultekin Gulsen
- Tu and Yuen Center for Functional Onco Imaging, Department of Radiological Sciences, University of California, Irvine, California 92697, USA
- Department of Biomedical Engineering, University of California, Irvine, California 92697, USA
| |
Collapse
|
17
|
Wang D, He J, Qiao H, Li P, Fan Y, Li D. Noncontact full-angle fluorescence molecular tomography system based on rotary mirrors. APPLIED OPTICS 2015; 54:7062-70. [PMID: 26368376 DOI: 10.1364/ao.54.007062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We propose a novel noncontact fluorescence molecular tomography system that achieves full-angle capacity with the use of a new rotary-mirrors-based imaging head. In the imaging head, four plane mirrors are mounted on a rotating gantry to enable illumination and detection over 360°. In comparison with existing full-angle systems, our system does not require rotation of the specimen animal, a large and heavy light source (with scanning head), or a bulky camera (with filters and lens). The system design and implementation are described in detail. Both physical phantom and in vivo experiments are performed to verify the performance of the proposed system.
Collapse
|
18
|
Chen D, Zhu S, Cao X, Zhao F, Liang J. X-ray luminescence computed tomography imaging based on X-ray distribution model and adaptively split Bregman method. BIOMEDICAL OPTICS EXPRESS 2015; 6:2649-2663. [PMID: 26203388 PMCID: PMC4505716 DOI: 10.1364/boe.6.002649] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/13/2015] [Accepted: 06/15/2015] [Indexed: 05/29/2023]
Abstract
X-ray luminescence computed tomography (XLCT) has become a promising imaging technology for biological application based on phosphor nanoparticles. There are mainly three kinds of XLCT imaging systems: pencil beam XLCT, narrow beam XLCT and cone beam XLCT. Narrow beam XLCT can be regarded as a balance between the pencil beam mode and the cone-beam mode in terms of imaging efficiency and image quality. The collimated X-ray beams are assumed to be parallel ones in the traditional narrow beam XLCT. However, we observe that the cone beam X-rays are collimated into X-ray beams with fan-shaped broadening instead of parallel ones in our prototype narrow beam XLCT. Hence we incorporate the distribution of the X-ray beams in the physical model and collected the optical data from only two perpendicular directions to further speed up the scanning time. Meanwhile we propose a depth related adaptive regularized split Bregman (DARSB) method in reconstruction. The simulation experiments show that the proposed physical model and method can achieve better results in the location error, dice coefficient, mean square error and the intensity error than the traditional split Bregman method and validate the feasibility of method. The phantom experiment can obtain the location error less than 1.1 mm and validate that the incorporation of fan-shaped X-ray beams in our model can achieve better results than the parallel X-rays.
Collapse
Affiliation(s)
- Dongmei Chen
- Engineering Research Center of Molecular and Neuro Imaging of Ministry of Education & School of Life Science and Technology, Xidian University, Xian, Shaanxi 710071,
China
| | - Shouping Zhu
- Engineering Research Center of Molecular and Neuro Imaging of Ministry of Education & School of Life Science and Technology, Xidian University, Xian, Shaanxi 710071,
China
| | - Xu Cao
- Engineering Research Center of Molecular and Neuro Imaging of Ministry of Education & School of Life Science and Technology, Xidian University, Xian, Shaanxi 710071,
China
| | - Fengjun Zhao
- Engineering Research Center of Molecular and Neuro Imaging of Ministry of Education & School of Life Science and Technology, Xidian University, Xian, Shaanxi 710071,
China
| | - Jimin Liang
- Engineering Research Center of Molecular and Neuro Imaging of Ministry of Education & School of Life Science and Technology, Xidian University, Xian, Shaanxi 710071,
China
| |
Collapse
|
19
|
Jermyn M, Kolste K, Pichette J, Sheehy G, Angulo-Rodríguez L, Paulsen KD, Roberts DW, Wilson BC, Petrecca K, Leblond F. Macroscopic-imaging technique for subsurface quantification of near-infrared markers during surgery. JOURNAL OF BIOMEDICAL OPTICS 2015; 20:036014. [PMID: 25793562 PMCID: PMC4367847 DOI: 10.1117/1.jbo.20.3.036014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 03/03/2015] [Indexed: 05/20/2023]
Abstract
Obtaining accurate quantitative information on the concentration and distribution of fluorescent markers lying at a depth below the surface of optically turbid media, such as tissue, is a significant challenge. Here, we introduce a fluorescence reconstruction technique based on a diffusion light transport model that can be used during surgery, including guiding resection of brain tumors, for depth-resolved quantitative imaging of near-infrared fluorescent markers. Hyperspectral fluorescence images are used to compute a topographic map of the fluorophore distribution, which yields structural and optical constraints for a three-dimensional subsequent hyperspectral diffuse fluorescence reconstruction algorithm. Using the model fluorophore Alexa Fluor 647 and brain-like tissue phantoms, the technique yielded estimates of fluorophore concentration within ±25% of the true value to depths of 5 to 9 mm, depending on the concentration. The approach is practical for integration into a neurosurgical fluorescence microscope and has potential to further extend fluorescence-guided resection using objective and quantified metrics of the presence of residual tumor tissue.
Collapse
Affiliation(s)
- Michael Jermyn
- McGill University, Brain Tumour Research Centre, Montreal Neurological Institute and Hospital, Department of Neurology and Neurosurgery, 3801 University Street, Montreal, Quebec H3A 2B4, Canada
- Polytechnique Montreal, Department of Engineering Physics, CP 6079, Succ. Centre-Ville, Montreal, Quebec H3C 3A7, Canada
| | - Kolbein Kolste
- Dartmouth College, Thayer School of Engineering, 14 Engineering Drive, Hanover, New Hampshire 03755, United States
| | - Julien Pichette
- Polytechnique Montreal, Department of Engineering Physics, CP 6079, Succ. Centre-Ville, Montreal, Quebec H3C 3A7, Canada
| | - Guillaume Sheehy
- Polytechnique Montreal, Department of Engineering Physics, CP 6079, Succ. Centre-Ville, Montreal, Quebec H3C 3A7, Canada
| | - Leticia Angulo-Rodríguez
- Polytechnique Montreal, Department of Engineering Physics, CP 6079, Succ. Centre-Ville, Montreal, Quebec H3C 3A7, Canada
| | - Keith D. Paulsen
- Dartmouth College, Thayer School of Engineering, 14 Engineering Drive, Hanover, New Hampshire 03755, United States
| | - David W. Roberts
- Dartmouth-Hitchcock Medical Center, Section of Neurosurgery, Lebanon, New Hampshire 03756, United States
| | - Brian C. Wilson
- University of Toronto/University Health Network, Department of Medical Biophysics, 101 College Street, Toronto, Ontario M5G 1L7, Canada
| | - Kevin Petrecca
- McGill University, Brain Tumour Research Centre, Montreal Neurological Institute and Hospital, Department of Neurology and Neurosurgery, 3801 University Street, Montreal, Quebec H3A 2B4, Canada
| | - Frederic Leblond
- Polytechnique Montreal, Department of Engineering Physics, CP 6079, Succ. Centre-Ville, Montreal, Quebec H3C 3A7, Canada
- Address all correspondence to: Frederic Leblond, E-mail:
| |
Collapse
|
20
|
Kang J, Chang JH, Wilson BC, Veilleux I, Bai Y, DaCosta R, Kim K, Ha S, Lee JG, Kim JS, Lee SG, Kim SM, Lee HJ, Ahn YB, Han S, Yoo Y, Song TK. A prototype hand-held tri-modal instrument for in vivo ultrasound, photoacoustic, and fluorescence imaging. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:034901. [PMID: 25832265 DOI: 10.1063/1.4915146] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Multi-modality imaging is beneficial for both preclinical and clinical applications as it enables complementary information from each modality to be obtained in a single procedure. In this paper, we report the design, fabrication, and testing of a novel tri-modal in vivo imaging system to exploit molecular/functional information from fluorescence (FL) and photoacoustic (PA) imaging as well as anatomical information from ultrasound (US) imaging. The same ultrasound transducer was used for both US and PA imaging, bringing the pulsed laser light into a compact probe by fiberoptic bundles. The FL subsystem is independent of the acoustic components but the front end that delivers and collects the light is physically integrated into the same probe. The tri-modal imaging system was implemented to provide each modality image in real time as well as co-registration of the images. The performance of the system was evaluated through phantom and in vivo animal experiments. The results demonstrate that combining the modalities does not significantly compromise the performance of each of the separate US, PA, and FL imaging techniques, while enabling multi-modality registration. The potential applications of this novel approach to multi-modality imaging range from preclinical research to clinical diagnosis, especially in detection/localization and surgical guidance of accessible solid tumors.
Collapse
Affiliation(s)
- Jeeun Kang
- Department of Electronic Engineering, Sogang University, Seoul 121-742, South Korea
| | - Jin Ho Chang
- Department of Electronic Engineering, Sogang University, Seoul 121-742, South Korea
| | - Brian C Wilson
- Princess Margaret Cancer Centre/University Health Network, Toronto, Ontario M5G 1L7, Canada
| | - Israel Veilleux
- Princess Margaret Cancer Centre/University Health Network, Toronto, Ontario M5G 1L7, Canada
| | - Yanhui Bai
- Princess Margaret Cancer Centre/University Health Network, Toronto, Ontario M5G 1L7, Canada
| | - Ralph DaCosta
- Princess Margaret Cancer Centre/University Health Network, Toronto, Ontario M5G 1L7, Canada
| | - Kang Kim
- Center for Ultrasound Molecular Imaging and Therapeutics, Department of Medicine, University of Pittsburgh School of Medicine and Heart and Vascular Institute, University of Pittsburgh Medical Center (UPMC), Pittsburgh, Pennsylvania 15213, USA
| | - Seunghan Ha
- Center for Ultrasound Molecular Imaging and Therapeutics, Department of Medicine, University of Pittsburgh School of Medicine and Heart and Vascular Institute, University of Pittsburgh Medical Center (UPMC), Pittsburgh, Pennsylvania 15213, USA
| | - Jong Gun Lee
- GE Ultrasound Korea, Seongnam 462-807, South Korea
| | | | | | - Sun Mi Kim
- Department of Radiology, Seoul National University of Bundang Hospital, Kyonggi-do, South Korea
| | - Hak Jong Lee
- Department of Radiology, Seoul National University of Bundang Hospital, Kyonggi-do, South Korea
| | - Young Bok Ahn
- Department of Electronic Engineering, Konkuk University, Seoul 143-701, South Korea
| | - Seunghee Han
- Sogang Institute of Advanced Technology, Sogang University, Seoul 121-742, South Korea
| | - Yangmo Yoo
- Department of Electronic Engineering, Sogang University, Seoul 121-742, South Korea
| | - Tai-Kyong Song
- Department of Electronic Engineering, Sogang University, Seoul 121-742, South Korea
| |
Collapse
|
21
|
Lee JH, Kim HK, Chandhanayingyong C, Lee FYI, Hielscher AH. Non-contact small animal fluorescence imaging system for simultaneous multi-directional angular-dependent data acquisition. BIOMEDICAL OPTICS EXPRESS 2014; 5:2301-16. [PMID: 25071965 PMCID: PMC4102365 DOI: 10.1364/boe.5.002301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 05/23/2014] [Accepted: 05/24/2014] [Indexed: 05/05/2023]
Abstract
We present a novel non-contact small animal fluorescent molecular tomography (FMT) imaging system. At the heart of the system is a new mirror-based imaging head that was designed to provide 360-degree measurement data from an entire animal surface in one step. This imaging head consists of two conical mirrors, which considerably reduce multiple back reflections between the animal and mirror surfaces. These back reflections are common in existing mirror-based imaging heads and tend to degrade the quality of raw measurement data. In addition, the introduction of a novel ray-transfer operator allows for the inclusion of the angular dependent data in the image reconstruction process, which results in higher image resolution. We describe in detail the system design and implementation of the hardware components as well as the transport-theory-based image reconstruction algorithm. Using numerical simulations, measurements on a well-defined phantom and a live animal, we evaluate the system performance and show the advantages of our approach.
Collapse
Affiliation(s)
- Jong Hwan Lee
- Department of Biomedical Engineering, Columbia University, 351 Engineering Terrace Mudd building, 500 West 120th Street, New York, NY, 10027, USA
| | - Hyun Keol Kim
- Department of Radiology, Columbia University Medical Center, 180 Fort Washington Avenue, New York, NY, 10032, USA
| | | | - Francis Young-In Lee
- Department of Orthopedic Surgery, Columbia University Medical Center, 650 West 168th Street, New York, NY, 10032, USA
| | - Andreas H. Hielscher
- Department of Biomedical Engineering, Columbia University, 351 Engineering Terrace Mudd building, 500 West 120th Street, New York, NY, 10027, USA
- Department of Radiology, Columbia University Medical Center, 180 Fort Washington Avenue, New York, NY, 10032, USA
- Department of Electrical Engineering, Columbia University, 1300 S. W. Mudd Building, 500 West 120th Street, New York, NY, 10027, USA
| |
Collapse
|
22
|
Hussain A, Daoudi K, Hondebrink E, Steenbergen W. Mapping optical fluence variations in highly scattering media by measuring ultrasonically modulated backscattered light. JOURNAL OF BIOMEDICAL OPTICS 2014; 19:066002. [PMID: 24887744 PMCID: PMC4041021 DOI: 10.1117/1.jbo.19.6.066002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 04/19/2014] [Accepted: 05/07/2014] [Indexed: 05/04/2023]
Abstract
Knowledge of the local optical fluence in biological tissue is of fundamental importance for biomedical optical techniques to achieve quantification. We report a method to noninvasively measure the local optical fluence in optically inhomogeneous scattering media. The concept is based on two aspects: the local tagging of light using ultrasonic modulation and the photon path reversibility principle. Our method has advantages over known computational-based fluence mapping techniques, for its purely experimental nature and without the requirement of prior knowledge of the optical properties of the medium. We provide a theoretical formalism and validation of the method with experiments in tissue-like phantoms. Further, we combine our method with photoacoustic imaging and compensate the photoacoustic signals for fluence variations in optically inhomogeneous media.
Collapse
Affiliation(s)
- Altaf Hussain
- University of Twente, MIRA Institute for Biomedical Technology and Technical Medicine, Biomedical Photonic Imaging Group, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Khalid Daoudi
- University of Twente, MIRA Institute for Biomedical Technology and Technical Medicine, Biomedical Photonic Imaging Group, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Erwin Hondebrink
- University of Twente, MIRA Institute for Biomedical Technology and Technical Medicine, Biomedical Photonic Imaging Group, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Wiendelt Steenbergen
- University of Twente, MIRA Institute for Biomedical Technology and Technical Medicine, Biomedical Photonic Imaging Group, P.O. Box 217, 7500 AE Enschede, The Netherlands
| |
Collapse
|
23
|
Li B, Berti R, Abran M, Lesage F. Ultrasound guided fluorescence molecular tomography with improved quantification by an attenuation compensated Born-normalization and in vivo preclinical study of cancer. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:053703. [PMID: 24880378 DOI: 10.1063/1.4875256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Ultrasound imaging, having the advantages of low-cost and non-invasiveness over MRI and X-ray CT, was reported by several studies as an adequate complement to fluorescence molecular tomography with the perspective of improving localization and quantification of fluorescent molecular targets in vivo. Based on the previous work, an improved dual-modality Fluorescence-Ultrasound imaging system was developed and then validated in imaging study with preclinical tumor model. Ultrasound imaging and a profilometer were used to obtain the anatomical prior information and 3D surface, separately, to precisely extract the tissue boundary on both sides of sample in order to achieve improved fluorescence reconstruction. Furthermore, a pattern-based fluorescence reconstruction on the detection side was incorporated to enable dimensional reduction of the dataset while keeping the useful information for reconstruction. Due to its putative role in the current imaging geometry and the chosen reconstruction technique, we developed an attenuation compensated Born-normalization method to reduce the attenuation effects and cancel off experimental factors when collecting quantitative fluorescence datasets over large area. Results of both simulation and phantom study demonstrated that fluorescent targets could be recovered accurately and quantitatively using this reconstruction mechanism. Finally, in vivo experiment confirms that the imaging system associated with the proposed image reconstruction approach was able to extract both functional and anatomical information, thereby improving quantification and localization of molecular targets.
Collapse
Affiliation(s)
- Baoqiang Li
- Institute of Biomedical Engineering, École Polytechnique de Montréal, Montreal, Quebec H3C 3A7, Canada
| | - Romain Berti
- Institute of Biomedical Engineering, École Polytechnique de Montréal, Montreal, Quebec H3C 3A7, Canada
| | - Maxime Abran
- Institute of Biomedical Engineering, École Polytechnique de Montréal, Montreal, Quebec H3C 3A7, Canada
| | - Frédéric Lesage
- Institute of Biomedical Engineering, École Polytechnique de Montréal, Montreal, Quebec H3C 3A7, Canada
| |
Collapse
|
24
|
Meaney PM, Golnabi AH, Epstein NR, Geimer SD, Fanning MW, Weaver JB, Paulsen KD. Integration of microwave tomography with magnetic resonance for improved breast imaging. Med Phys 2014; 40:103101. [PMID: 24089930 DOI: 10.1118/1.4820361] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
PURPOSE Breast magnetic resonance imaging is highly sensitive but not very specific for the detection of breast cancer. Opportunities exist to supplement the image acquisition with a more specific modality provided the technical challenges of meeting space limitations inside the bore, restricted breast access, and electromagnetic compatibility requirements can be overcome. Magnetic resonance (MR) and microwave tomography (MT) are complementary and synergistic because the high resolution of MR is used to encode spatial priors on breast geometry and internal parenchymal features that have distinct electrical properties (i.e., fat vs fibroglandular tissue) for microwave tomography. METHODS The authors have overcome integration challenges associated with combining MT with MR to produce a new coregistered, multimodality breast imaging platform--magnetic resonance microwave tomography, including: substantial illumination tank size reduction specific to the confined MR bore diameter, minimization of metal content and composition, reduction of metal artifacts in the MR images, and suppression of unwanted MT multipath signals. RESULTS MR SNR exceeding 40 dB can be obtained. Proper filtering of MR signals reduces MT data degradation allowing MT SNR of 20 dB to be obtained, which is sufficient for image reconstruction. When MR spatial priors are incorporated into the recovery of MT property estimates, the errors between the recovered versus actual dielectric properties approach 5%. CONCLUSIONS The phantom and human subject exams presented here are the first demonstration of combining MT with MR to improve the accuracy of the reconstructed MT images.
Collapse
Affiliation(s)
- Paul M Meaney
- Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755
| | | | | | | | | | | | | |
Collapse
|
25
|
Luk AT, Ha S, Nouizi F, Thayer D, Lin Y, Gulsen G. A True Multi-modality Approach for High Resolution Optical Imaging: Photo-Magnetic Imaging. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2014; 8937. [PMID: 25767691 DOI: 10.1117/12.2040870] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Multi-modality imaging leverages the competitive advantage of different imaging systems to improve the overall resolution and quantitative accuracy. Our new technique, Photo-Magnetic Imaging (PMI) is one of these true multi-modality imaging approaches, which can provide quantitative optical absorption map at MRI spatial resolution. PMI uses laser light to illuminate tissue and elevate its temperature while utilizing MR thermometry to measure the laser-induced temperature variation with high spatial resolution. The high-resolution temperature maps are later converted to tissue absorption maps by a finite element based inverse solver that is based on modeling of photon migration and heat diffusion in tissue. Previously, we have demonstrated the feasibility of PMI with phantom studies. Recently, we have managed to reduce the laser power under ANSI limit for maximum skin exposure therefore, we have well positioned PMI for in vivo imaging. Currently we are expanding our system by adding multi-wavelength imaging capability. This will allow us not only to resolve spatial distribution of tissue chromophores but also exogenous contrast agents. Although we test PMIs feasibility with animal studies, our future goal is to use PMI for breast cancer imaging due to its high translational potential.
Collapse
Affiliation(s)
- Alex T Luk
- Tu and Yuen Center for Functional Onco-Imaging and Department of Radiological Sciences, University of California Irvine, Irvine, CA, United States
| | - Seunghoon Ha
- Tu and Yuen Center for Functional Onco-Imaging and Department of Radiological Sciences, University of California Irvine, Irvine, CA, United States
| | - Farouk Nouizi
- Tu and Yuen Center for Functional Onco-Imaging and Department of Radiological Sciences, University of California Irvine, Irvine, CA, United States
| | - David Thayer
- Tu and Yuen Center for Functional Onco-Imaging and Department of Radiological Sciences, University of California Irvine, Irvine, CA, United States
| | - Yuting Lin
- Tu and Yuen Center for Functional Onco-Imaging and Department of Radiological Sciences, University of California Irvine, Irvine, CA, United States
| | - Gultekin Gulsen
- Tu and Yuen Center for Functional Onco-Imaging and Department of Radiological Sciences, University of California Irvine, Irvine, CA, United States ; Department of Biomedical Engineering, University of California Irvine, California 92697
| |
Collapse
|
26
|
Zhang B, Gao F, Wang M, Cao X, Liu F, Wang X, Luo J, Wang G, Bai J. In vivo tomographic imaging of lung colonization of tumour in mouse with simultaneous fluorescence and X-ray CT. JOURNAL OF BIOPHOTONICS 2014; 7:110-116. [PMID: 23696158 DOI: 10.1002/jbio.201300037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 04/01/2013] [Accepted: 04/29/2013] [Indexed: 06/02/2023]
Abstract
Non-invasive in vivo imaging of diffuse and wide-spread colonization within the lungs, rather than distinct solid primary tumors, is still a challenging work. In this work, a lung colonization mouse model bearing A549 human lung tumor was simultaneously scanned by a dual-modality fluorescence molecular tomography (FMT) and X-ray computed tomography (CT) system in vivo. A two steps method which incorporates CT structural information into the FMT reconstruction procedure is employed to provide concurrent anatomical and functional information. By using the target-specific fluorescence agent, the fluorescence tomographic results show elevated fluorescence intensity deep within the lungs which is colonized with diffuse and wide-spread tumors. The results were confirmed with ex vivo fluorescence reflectance imaging and histological examination of the lung tissues. With FMT reconstruction combined with the CT information, the dual-modality FMT/micro-CT system is expected to offer sensitive and noninvasive imaging of diffuse tumor colonization within the lungs in vivo.
Collapse
Affiliation(s)
- Bin Zhang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, 100084, China
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Darne C, Lu Y, Sevick-Muraca EM. Small animal fluorescence and bioluminescence tomography: a review of approaches, algorithms and technology update. Phys Med Biol 2013; 59:R1-64. [PMID: 24334634 DOI: 10.1088/0031-9155/59/1/r1] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Emerging fluorescence and bioluminescence tomography approaches have several common, yet several distinct features from established emission tomographies of PET and SPECT. Although both nuclear and optical imaging modalities involve counting of photons, nuclear imaging techniques collect the emitted high energy (100-511 keV) photons after radioactive decay of radionuclides while optical techniques count low-energy (1.5-4.1 eV) photons that are scattered and absorbed by tissues requiring models of light transport for quantitative image reconstruction. Fluorescence imaging has been recently translated into clinic demonstrating high sensitivity, modest tissue penetration depth, and fast, millisecond image acquisition times. As a consequence, the promise of quantitative optical tomography as a complement of small animal PET and SPECT remains high. In this review, we summarize the different instrumentation, methodological approaches and schema for inverse image reconstructions for optical tomography, including luminescence and fluorescence modalities, and comment on limitations and key technological advances needed for further discovery research and translation.
Collapse
|
28
|
Lin Y, Gao H, Thayer D, Luk AL, Gulsen G. Photo-magnetic imaging: resolving optical contrast at MRI resolution. Phys Med Biol 2013; 58:3551-62. [PMID: 23640084 DOI: 10.1088/0031-9155/58/11/3551] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In this paper, we establish the mathematical framework of a novel imaging technique, namely photo-magnetic imaging (PMI). PMI uses a laser to illuminate biological tissues and measure the induced temperature variations using magnetic resonance imaging (MRI). PMI overcomes the limitation of conventional optical imaging and allows imaging of the optical contrast at MRI spatial resolution. The image reconstruction for PMI, using a finite-element-based algorithm with an iterative approach, is presented in this paper. The quantitative accuracy of PMI is investigated for various inclusion sizes, depths and absorption values. Then, a comparison between conventional diffuse optical tomography (DOT) and PMI is carried out to illustrate the superior performance of PMI. An example is presented showing that two 2 mm diameter inclusions embedded 4.5 mm deep and located side by side in a 25 mm diameter circular geometry medium are recovered as a single 6 mm diameter object with DOT. However, these two objects are not only effectively resolved with PMI, but their true concentrations are also recovered successfully.
Collapse
Affiliation(s)
- Yuting Lin
- Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, University of California, Irvine, CA, USA.
| | | | | | | | | |
Collapse
|
29
|
Pu H, He W, Zhang G, Zhang B, Liu F, Zhang Y, Luo J, Bai J. Separating structures of different fluorophore concentrations by principal component analysis on multispectral excitation-resolved fluorescence tomography images. BIOMEDICAL OPTICS EXPRESS 2013; 4:1829-45. [PMID: 24156047 PMCID: PMC3799649 DOI: 10.1364/boe.4.001829] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 08/01/2013] [Accepted: 08/05/2013] [Indexed: 05/03/2023]
Abstract
Multispectral excitation-resolved fluorescence tomography (MEFT) uses excitation light of different wavelengths to illuminate the fluorophores and obtains the reconstruction image frame which is fluorescence yield at each corresponding wavelength. For structures containing fluorophores of different concentrations, fluorescence yields show different variation trends with the excitation spectrum. In this study, principal component analysis (PCA) is used to analyze the MEFT reconstructed image frames. By taking advantage of the different variation trends of fluorescence yields, PCA can provide a set of principal components (PCs) in which structures containing different concentrations of fluorophores are shown separately. Simulations and experiments are both performed to test the performance of the proposed algorithm. The results suggest that the location and structure of fluorophores with different concentrations can be obtained and the contrast of fluorophores can be improved further by using this algorithm.
Collapse
Affiliation(s)
- Huangsheng Pu
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China
- Department of Computer Application, School of Biomedical Engineering, Fourth Military Medical University, Xi’an710032, China
| | - Wei He
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Guanglei Zhang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Bin Zhang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Fei Liu
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Yi Zhang
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China
| | - Jianwen Luo
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China
- Center for Biomedical Imaging Research, Tsinghua University, Beijing 100084, China
| | - Jing Bai
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China
| |
Collapse
|
30
|
Liu F, Li M, Zhang B, Luo J, Bai J. Weighted depth compensation algorithm for fluorescence molecular tomography reconstruction. APPLIED OPTICS 2012; 51:8883-92. [PMID: 23262629 DOI: 10.1364/ao.51.008883] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Accepted: 10/16/2012] [Indexed: 05/26/2023]
Abstract
In fluorescence molecular tomography (FMT), diffuse-light measurements are obtained from a series of source-detector pairs placed on the boundary of the medium. The sensitivity of measurements deteriorates quickly with increased distance from the sources and detectors and therefore yields poor depth quantitative recovery. A depth compensation algorithm is presented in this paper to reconstruct fluorescent inclusions in deep tissues. Two weight matrixes are employed to level off sensitivity differences and enhance prominent elements of the solution. Results of numerical and phantom experiments demonstrate that both relative quantitation and spatial resolution of FMT are improved for inclusions at different depths.
Collapse
Affiliation(s)
- Fei Liu
- Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, China
| | | | | | | | | |
Collapse
|
31
|
Ma W, Zhang W, Yi X, Li J, Wu L, Wang X, Zhang L, Zhou Z, Zhao H, Gao F. Time-domain fluorescence-guided diffuse optical tomography based on the third-order simplified harmonics approximation. APPLIED OPTICS 2012; 51:8656-8668. [PMID: 23262607 DOI: 10.1364/ao.51.008656] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2012] [Accepted: 11/15/2012] [Indexed: 06/01/2023]
Abstract
Extensive efforts have been made to integrate diffuse optical tomography (DOT) with other imaging modalities, such as magnetic-resonance imaging and x-ray computerized tomography, for its performance improvement. However, the experimental apparatus is in general intricate and costly due to adoption of the physically distinct radiation regimes. In this study, a time-domain fluorescence-guided DOT methodology that incorporates a priori localization information provided by diffuse fluorescence tomography (DFT) is investigated in an attempt to optimize recovery of the optical property distributions. The methodology is based on a specifically designed multichannel time-correlated single-photon-counting DOT/DFT system as well as a featured-data image reconstruction scheme that is developed within the framework of the generalized pulse spectrum technique and employs the third-order simplified harmonics approximation to the radiative transfer equation as the forward model. We have validated the methodology using phantom experiments and demonstrated that, with the guidance of fluorescence a priori, the quantitativeness and spatial resolution of the recovered optical target can be considerably improved in terms of the absorption and scattering images.
Collapse
Affiliation(s)
- Wenjuan Ma
- College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Lin Y, Ghijsen M, Nalcioglu O, Gulsen G. In vivo validation of quantitative frequency domain fluorescence tomography. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:126021. [PMID: 23323291 PMCID: PMC3525318 DOI: 10.1117/1.jbo.17.12.126021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We have developed a hybrid frequency domain fluorescence tomography and magnetic resonance imaging system (MRI) for small animal imaging. The main purpose of this system is to obtain quantitatively accurate fluorescence concentration and lifetime images using a multi-modality approach. In vivo experiments are undertaken to evaluate the system. We compare the recovered fluorescence parameters with and without MRI structural a priori information. In addition, we compare two optical background heterogeneity correction methods: Born normalization and utilizing diffuse optical tomography (DOT) functional a priori information. The results show that the concentration and lifetime of a 4.2-mm diameter indocyanine green inclusion located 15 mm deep inside a rat can be recovered with less than a 5% error when functional a priori information from DOT and structural a priori information from MRI are utilized.
Collapse
Affiliation(s)
- Yuting Lin
- University of California, Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, 164 Irvine Hall, Irvine, California 92697
| | - Michael Ghijsen
- University of California, Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, 164 Irvine Hall, Irvine, California 92697
| | - Orhan Nalcioglu
- University of California, Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, 164 Irvine Hall, Irvine, California 92697
| | - Gultekin Gulsen
- University of California, Tu and Yuen Center for Functional Onco-Imaging, Department of Radiological Sciences, 164 Irvine Hall, Irvine, California 92697
- Address all correspondence to: Gultekin Gulsen, University of California, Tu and Yuen Center for Functional Onco-Imaging, 164 Irvine Hall, Irvine, California 92697. Tel: 949 824 6557; Fax: 949 824 3481; E-mail:
| |
Collapse
|
33
|
Liu X, Zhang B, Luo J, Bai J. 4-D reconstruction for dynamic fluorescence diffuse optical tomography. IEEE TRANSACTIONS ON MEDICAL IMAGING 2012; 31:2120-2132. [PMID: 22910097 DOI: 10.1109/tmi.2012.2213828] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Dynamic fluorescence diffuse optical tomography (FDOT) is important for the research of drug delivery, medical diagnosis and treatment. Conventionally, dynamic tomographic images are reconstructed frame by frame, independently. This approach fails to account for the temporal correlations in measurement data. Ideally, the entire image sequence should be considered as a whole and a four-dimensional (4-D) reconstruction should be performed. However, the fully 4-D reconstruction is computationally intensive. In this paper, we propose a new 4-D reconstruction approach for dynamic FDOT, which is achieved by applying a temporal Karhunen-Loève (KL) transformation to the imaging equation. By taking advantage of the decorrelation and compression properties of the KL transformation, the complex 4-D optical reconstruction problem is greatly simplified. To evaluate the performance of the method, simulation, phantom, and in vivo experiments (N=7) are performed on a hybrid FDOT/x-ray computed tomography imaging system. The experimental results indicate that the reconstruction images obtained by the KL method provide good reconstruction quality. Additionally, by discarding high-order KL components, the computation time involved with fully 4-D reconstruction can be greatly reduced in contrast to the conventional frame-by-frame reconstruction.
Collapse
|
34
|
Quan G, Wang K, Yang X, Deng Y, Luo Q, Gong H. Micro-computed tomography-guided, non-equal voxel Monte Carlo method for reconstruction of fluorescence molecular tomography. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:086006. [PMID: 23224193 DOI: 10.1117/1.jbo.17.8.086006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The study of dual-modality technology which combines microcomputed tomography (micro-CT) and fluorescence molecular tomography (FMT) has become one of the main focuses in FMT. However, because of the diversity of the optical properties and irregular geometry for small animals, a reconstruction method that can effectively utilize the high-resolution structural information of micro-CT for tissue with arbitrary optical properties is still one of the most challenging problems in FMT. We develop a micro-CT-guided non-equal voxel Monte Carlo method for FMT reconstruction. With the guidance of micro-CT, precise voxel binning can be conducted on the irregular boundary or region of interest. A modified Laplacian regularization method is also proposed to accurately reconstruct the distribution of the fluorescent yield for non-equal space voxels. Simulations and phantom experiments show that this method not only effectively reduces the loss of high-resolution structural information of micro-CT in irregular boundaries and increases the accuracy of the FMT algorithm in both forward and inverse problems, but the method also has a small Jacobian matrix and a short reconstruction time. At last, we performed small animal imaging to validate our method.
Collapse
Affiliation(s)
- Guotao Quan
- Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, 1037 Luoyu Road, Wuhan 430074, China
| | | | | | | | | | | |
Collapse
|
35
|
Tichauer KM, Holt RW, Samkoe KS, El-Ghussein F, Gunn JR, Jermyn M, Dehghani H, Leblond F, Pogue BW. Computed tomography-guided time-domain diffuse fluorescence tomography in small animals for localization of cancer biomarkers. J Vis Exp 2012:e4050. [PMID: 22847515 PMCID: PMC3476420 DOI: 10.3791/4050] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Small animal fluorescence molecular imaging (FMI) can be a powerful tool for preclinical drug discovery and development studies. However, light absorption by tissue chromophores (e.g., hemoglobin, water, lipids, melanin) typically limits optical signal propagation through thicknesses larger than a few millimeters. Compared to other visible wavelengths, tissue absorption for red and near-infrared (near-IR) light absorption dramatically decreases and non-elastic scattering becomes the dominant light-tissue interaction mechanism. The relatively recent development of fluorescent agents that absorb and emit light in the near-IR range (600-1000 nm), has driven the development of imaging systems and light propagation models that can achieve whole body three-dimensional imaging in small animals. Despite great strides in this area, the ill-posed nature of diffuse fluorescence tomography remains a significant problem for the stability, contrast recovery and spatial resolution of image reconstruction techniques and the optimal approach to FMI in small animals has yet to be agreed on. The majority of research groups have invested in charge-coupled device (CCD)-based systems that provide abundant tissue-sampling but suboptimal sensitivity, while our group and a few others have pursued systems based on very high sensitivity detectors, that at this time allow dense tissue sampling to be achieved only at the cost of low imaging throughput. Here we demonstrate the methodology for applying single-photon detection technology in a fluorescence tomography system to localize a cancerous brain lesion in a mouse model. The fluorescence tomography (FT) system employed single photon counting using photomultiplier tubes (PMT) and information-rich time-domain light detection in a non-contact conformation. This provides a simultaneous collection of transmitted excitation and emission light, and includes automatic fluorescence excitation exposure control, laser referencing, and co-registration with a small animal computed tomography (microCT) system. A nude mouse model was used for imaging. The animal was inoculated orthotopically with a human glioma cell line (U251) in the left cerebral hemisphere and imaged 2 weeks later. The tumor was made to fluoresce by injecting a fluorescent tracer, IRDye 800CW-EGF (LI-COR Biosciences, Lincoln, NE) targeted to epidermal growth factor receptor, a cell membrane protein known to be overexpressed in the U251 tumor line and many other cancers. A second, untargeted fluorescent tracer, Alexa Fluor 647 (Life Technologies, Grand Island, NY) was also injected to account for non-receptor mediated effects on the uptake of the targeted tracers to provide a means of quantifying tracer binding and receptor availability/density. A CT-guided, time-domain algorithm was used to reconstruct the location of both fluorescent tracers (i.e., the location of the tumor) in the mouse brain and their ability to localize the tumor was verified by contrast-enhanced magnetic resonance imaging. Though demonstrated for fluorescence imaging in a glioma mouse model, the methodology presented in this video can be extended to different tumor models in various small animal models potentially up to the size of a rat.
Collapse
|
36
|
Lapointe E, Pichette J, Bérubé-Lauzière Y. A multi-view time-domain non-contact diffuse optical tomography scanner with dual wavelength detection for intrinsic and fluorescence small animal imaging. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:063703. [PMID: 22755630 DOI: 10.1063/1.4726016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We present a non-contact diffuse optical tomography (DOT) scanner with multi-view detection (over 360°) for localizing fluorescent markers in scattering and absorbing media, in particular small animals. It relies on time-domain detection after short pulse laser excitation. Ultrafast time-correlated single photon counting and photomultiplier tubes are used for time-domain measurements. For light collection, seven free-space optics non-contact dual wavelength detection channels comprising 14 detectors overall are placed around the subject, allowing the measurement of time point-spread functions at both excitation and fluorescence wavelengths. The scanner is endowed with a stereo camera pair for measuring the outer shape of the subject in 3D. Surface and DOT measurements are acquired simultaneously with the same laser beam. The hardware and software architecture of the scanner are discussed. Phantoms are used to validate the instrument. Results on the localization of fluorescent point-like inclusions immersed in a scattering and absorbing object are presented. The localization algorithm relies on distance ranging based on the measurement of early photons arrival times at different positions around the subject. This requires exquisite timing accuracy from the scanner. Further exploiting this capability, we show results on the effect of a scattering hetereogenity on the arrival time of early photons. These results demonstrate that our scanner provides all that is necessary for reconstructing images of small animals using full tomographic reconstruction algorithms, which will be the next step. Through its free-space optics design and the short pulse laser used, our scanner shows unprecedented timing resolution compared to other multi-view time-domain scanners.
Collapse
Affiliation(s)
- Eric Lapointe
- Laboratoire TomOptUS, Département de génie électrique et de génie informatique, Université de Sherbrooke, 2500 boul. Université, Sherbrooke, Québec J1K 2R1, Canada
| | | | | |
Collapse
|
37
|
Yang X, Gong H, Fu J, Quan G, Huang C, Luo Q. Molecular imaging of small animals with fluorescent proteins: from projection to multimodality. Comput Med Imaging Graph 2012; 36:259-63. [PMID: 22030093 DOI: 10.1016/j.compmedimag.2011.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 08/26/2011] [Accepted: 09/22/2011] [Indexed: 10/16/2022]
Abstract
Fluorescent proteins (FPs) have been widely adopted in cell research for protein trafficking and reporter gene expression studies, as well as to study other biological processes. However, biological tissue has high light scattering and high absorption coefficients of visible light; hence, using FPs in small animal imaging remains a challenge, especially when the FPs are located deep in the tissue. In small animals, fluorescence molecular imaging could potentially address this difficulty. We constructed fluorescence molecular imaging systems that have two modes: a planner mode (projection imaging) and a multimodality mode (fluorescence molecular tomography and micro-CT). The planner mode can provide projection images of a fluorophore in the whole body of a small animal, whereas three-dimensional information can be offered by multimodality mode. The planner imaging system works in the reflection mode and is designed to provide fast imaging. The multimodality imaging system is designed to allow quantification and three-dimensional localization of fluorophores. A nude mouse with a tumour targeted with a far-red FP, which is appropriate for in vivo imaging, was adopted to validate the two systems. The results indicate that the planner imaging system is probably suitable for high throughput molecular imaging, whereas the multimodality imaging system is fit for quantitative research.
Collapse
Affiliation(s)
- Xiaoquan Yang
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology, PR China.
| | | | | | | | | | | |
Collapse
|
38
|
Ale A, Ermolayev V, Herzog E, Cohrs C, de Angelis MH, Ntziachristos V. FMT-XCT: in vivo animal studies with hybrid fluorescence molecular tomography-X-ray computed tomography. Nat Methods 2012; 9:615-20. [PMID: 22561987 DOI: 10.1038/nmeth.2014] [Citation(s) in RCA: 175] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 04/02/2012] [Indexed: 11/09/2022]
Abstract
The development of hybrid optical tomography methods to improve imaging performance has been suggested over a decade ago and has been experimentally demonstrated in animals and humans. Here we examined in vivo performance of a camera-based hybrid fluorescence molecular tomography (FMT) system for 360° imaging combined with X-ray computed tomography (XCT). Offering an accurately co-registered, information-rich hybrid data set, FMT-XCT has new imaging possibilities compared to stand-alone FMT and XCT. We applied FMT-XCT to a subcutaneous 4T1 tumor mouse model, an Aga2 osteogenesis imperfecta model and a Kras lung cancer mouse model, using XCT information during FMT inversion. We validated in vivo imaging results against post-mortem planar fluorescence images of cryoslices and histology data. Besides offering concurrent anatomical and functional information, FMT-XCT resulted in the most accurate FMT performance to date. These findings indicate that addition of FMT optics into the XCT gantry may be a potent upgrade for small-animal XCT systems.
Collapse
Affiliation(s)
- Angelique Ale
- Technische Universität München and Helmholtz Zentrum München, Institute for Biological and Medical Imaging, Neuherberg, Germany
| | | | | | | | | | | |
Collapse
|
39
|
Yan H, Lin Y, Barber WC, Unlu MB, Gulsen G. A gantry-based tri-modality system for bioluminescence tomography. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:043708. [PMID: 22559540 PMCID: PMC3350538 DOI: 10.1063/1.3698295] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
A gantry-based tri-modality system that combines bioluminescence (BLT), diffuse optical (DOT), and x-ray computed tomography (XCT) into the same setting is presented here. The purpose of this system is to perform bioluminescence tomography using a multi-modality imaging approach. As parts of this hybrid system, XCT and DOT provide anatomical information and background optical property maps. This structural and functional a priori information is used to guide and restrain bioluminescence reconstruction algorithm and ultimately improve the BLT results. The performance of the combined system is evaluated using multi-modality phantoms. In particular, a cylindrical heterogeneous multi-modality phantom that contains regions with higher optical absorption and x-ray attenuation is constructed. We showed that a 1.5 mm diameter bioluminescence inclusion can be localized accurately with the functional a priori information while its source strength can be recovered more accurately using both structural and the functional a priori information.
Collapse
Affiliation(s)
- Han Yan
- Tu and Yuen Center for Functional Onco-Imaging and Department of Radiological Sciences, University of California, Irvine, California 92697, USA
| | | | | | | | | |
Collapse
|
40
|
Yi H, Chen D, Qu X, Peng K, Chen X, Zhou Y, Tian J, Liang J. Multilevel, hybrid regularization method for reconstruction of fluorescent molecular tomography. APPLIED OPTICS 2012; 51:975-86. [PMID: 22410902 DOI: 10.1364/ao.51.000975] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 11/19/2011] [Indexed: 05/20/2023]
Abstract
In this paper, a multilevel, hybrid regularization method is presented for fluorescent molecular tomography (FMT) based on the hp-finite element method (hp-FEM) with a continuous wave. The hybrid regularization method combines sparsity regularization and Landweber iterative regularization to improve the stability of the solution of the ill-posed inverse problem. In the first coarse mesh level, considering the fact that the fluorescent probes are sparsely distributed in the entire reconstruction region in most FMT applications, the sparse regularization method is employed to take full advantage of this sparsity. In the subsequent refined mesh levels, since the reconstruction region is reduced and the initial value of the unknown parameters is provided from the previous mesh, these mesh levels seem to be different from the first level. As a result, the Landweber iterative regularization method is applied for reconstruction. Simulation experiments on a 3D digital mouse atlas and physical experiments on a phantom are conducted to evaluate the performance of our method. The reconstructed results show the potential and feasibility of the proposed approach.
Collapse
Affiliation(s)
- Huangjian Yi
- Life Sciences Research Center, School of Life Sciences and Technology, Xidian University, Xi'an, Shaanxi 710071, China
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Lin Y, Bolisay L, Ghijsen M, Kwong TC, Gulsen G. Temperature-modulated fluorescence tomography in a turbid media. APPLIED PHYSICS LETTERS 2012; 100:73702-737024. [PMID: 22393266 PMCID: PMC3292592 DOI: 10.1063/1.3681378] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 01/05/2012] [Indexed: 05/25/2023]
Abstract
High scattering in biological tissues makes fluorescence tomography inverse problem very challenging in thick medium. We describe an approach termed "temperature-modulated fluorescence tomography" that can acquire fluorescence images at focused ultrasound resolution. By utilizing recently emerged temperature sensitive fluorescence contrast agents, this technique provides fluorescence images with high resolution prior to any reconstruction process. We demonstrate that this technique is well suited to resolve small fluorescence targets located several centimeters deep in tissue.
Collapse
|
42
|
Normalized Born Approximation-Based Two-Stage Reconstruction Algorithm for Quantitative Fluorescence Molecular Tomography. JOURNAL OF ELECTRICAL AND COMPUTER ENGINEERING 2012. [DOI: 10.1155/2012/838967] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Fluorescence molecular tomography (FMT) is a promising technique forin vivosmall animal imaging. In this paper, a two-stage reconstruction method based on normalized Born approximation is developed for FMT, which includes two steps for quantitative reconstruction. First, the localization of fluorescent fluorophore is determined byl1-norm regularization method. Then, in the location region of fluorophore, which is provided by the first stage, algebraic reconstruction technique (ART) is utilized for the fluorophore concentration reconstruction. The validity of the two-stage quantitative reconstruction algorithm is testified by simulation experiments on a 3D digital mouse atlas and physical experiments on a phantom. The results suggest that we are able to recover the fluorophore location and concentration.
Collapse
|
43
|
Li B, Abran M, Matteau-Pelletier C, Rouleau L, Lam T, Sharma R, Rhéaume E, Kakkar A, Tardif JC, Lesage F. Low-cost three-dimensional imaging system combining fluorescence and ultrasound. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:126010. [PMID: 22191927 DOI: 10.1117/1.3662455] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
In this paper, we present a dual-modality imaging system combining three-dimensional (3D) continuous-wave transillumination fluorescence tomography with 3D ultrasound (US) imaging. We validated the system with two phantoms, one containing fluorescent inclusions (Cy5.5) at different depths, and another varying-thickness semicylindrical phantom. Using raster scanning, the combined fluorescence/US system was used to collect the boundary fluorescent emission in the X-Y plane, as well as recovered the 3D surface and position of the inclusions from US signals. US images were segmented to provide soft priors for the fluorescence image reconstruction. Phantom results demonstrated that with priors derived from the US images, the fluorescent reconstruction quality was significantly improved. As further evaluation, we show pilot in vivo results using an Apo-E mouse to assess the feasibility and performance of this system in animal studies. Limitations and potential to be used in artherosclerosis studies are then discussed.
Collapse
Affiliation(s)
- Baoqiang Li
- École Polytechnique de Montréal, Institute of Biomedical Engineering, Montreal, H3C 3A7, Canada
| | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Ardeshirpour Y, Chernomordik V, Capala J, Hassan M, Zielinsky R, Griffiths G, Achilefu S, Smith P, Gandjbakhckhe A. Using in-vivo fluorescence imaging in personalized cancer diagnostics and therapy, an image and treat paradigm. Technol Cancer Res Treat 2011; 10:549-60. [PMID: 22066595 PMCID: PMC3718028 DOI: 10.1177/153303461101000605] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The major goal in developing drugs targeting specific tumor receptors, such as Monoclonal AntiBodies (MAB), is to make a drug compound that targets selectively the cancer-causing biomarkers, inhibits their functionality, and/or delivers the toxin specifically to the malignant cells. Recent advances in MABs show that their efficacy depends strongly on characterization of tumor biomarkers. Therefore, one of the main tasks in cancer diagnostics and treatment is to develop non-invasive in-vivo imaging techniques for detection of cancer biomarkers and monitoring their down regulation during the treatment. Such methods can potentially result in a new imaging and treatment paradigm for cancer therapy. In this article we have reviewed fluorescence imaging approaches, including those developed in our group, to detect and monitor Human Epidermal Growth Factor 2 (HER2) receptors before and during therapy. Transition of these techniques from the bench to bedside is the ultimate goal of our project. Similar approaches can be used potentially for characterization of other cancer related cell biomarkers.
Collapse
Affiliation(s)
- Yasaman Ardeshirpour
- NIH/National Institute of Child Health and Human Development, Building 9, 9 Memorial Dr., Bethesda, MD, 20892
| | - Victor Chernomordik
- NIH/National Institute of Child Health and Human Development, Building 9, 9 Memorial Dr., Bethesda, MD, 20892
| | - Jacek Capala
- NIH/National Cancer Institute, Building 10-Magnuson Clinical Center, 10 Center Dr, Bethesda, MD, 20892
| | - Moinuddin Hassan
- NIH/National Institute of Child Health and Human Development, Building 9, 9 Memorial Dr., Bethesda, MD, 20892
| | - Rafal Zielinsky
- NIH/National Cancer Institute, Building 10-Magnuson Clinical Center, 10 Center Dr, Bethesda, MD, 20892
| | - Gary Griffiths
- NIH/Imaging Probe Development Center, Building 9800, Medical Center Dr., Rockville, MD, 20850
| | - Samuel Achilefu
- Optical Radiology Lab, Department of Radiology, Washington University, 4525 Scott Avenue, St. Louis, MO 63110
| | - Paul Smith
- NIH/National Institute of Biomedical Imaging and Bioengineering, Building 13, 3N18A 13 South Dr, Bethesda, MD, 20892
| | - Amir Gandjbakhckhe
- NIH/National Institute of Child Health and Human Development, Building 9, 9 Memorial Dr., Bethesda, MD, 20892
| |
Collapse
|
45
|
Pogue BW, Davis SC, Leblond F, Mastanduno MA, Dehghani H, Paulsen KD. Implicit and explicit prior information in near-infrared spectral imaging: accuracy, quantification and diagnostic value. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2011; 369:4531-57. [PMID: 22006905 PMCID: PMC3263784 DOI: 10.1098/rsta.2011.0228] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Near-infrared spectroscopy (NIRS) of tissue provides quantification of absorbers, scattering and luminescent agents in bulk tissue through the use of measurement data and assumptions. Prior knowledge can be critical about things such as (i) the tissue shape and/or structure, (ii) spectral constituents, (iii) limits on parameters, (iv) demographic or biomarker data, and (v) biophysical models of the temporal signal shapes. A general framework of NIRS imaging with prior information is presented, showing that prior information datasets could be incorporated at any step in the NIRS process, with the general workflow being: (i) data acquisition, (ii) pre-processing, (iii) forward model, (iv) inversion/reconstruction, (v) post-processing, and (vi) interpretation/diagnosis. Most of the development in NIRS has used ad hoc or empirical implementations of prior information such as pre-measured absorber or fluorophore spectra, or tissue shapes as estimated by additional imaging tools. A comprehensive analysis would examine what prior information maximizes the accuracy in recovery and value for medical diagnosis, when implemented at separate stages of the NIRS sequence. Individual applications of prior information can show increases in accuracy or improved ability to estimate biochemical features of tissue, while other approaches may not. Most beneficial inclusion of prior information has been in the inversion/reconstruction process, because it solves the mathematical intractability. However, it is not clear that this is always the most beneficial stage.
Collapse
Affiliation(s)
- Brian W Pogue
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA.
| | | | | | | | | | | |
Collapse
|
46
|
Pyka T, Schulz R, Ale A, Ntziachristos V. Revisiting the normalized Born approximation: effects of scattering. OPTICS LETTERS 2011; 36:4329-31. [PMID: 22089553 DOI: 10.1364/ol.36.004329] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The normalized Born approximation has been suggested as a ratiometric method in fluorescence molecular tomography (FMT) applications, to account for heterogeneity variations. The method enabled practical inversions, as it offered fluorescence reconstruction accuracy over a wide range of absorption heterogeneity, while also accounting for unknown experimental factors, such as the various system gains and losses. Yet it was noted that scattering variations affect the robustness and accuracy. Herein we decompose the effects of absorption and scattering and capitalize on the recent development of hybrid FMT/x-ray computed tomography imaging methods to proposed amendments to the method, which improve the overall accuracy of the approach.
Collapse
Affiliation(s)
- Thomas Pyka
- Institute for Biological and Medical Imaging, Technische Universität München and Helmholtz Zentrum München, Neuherberg, Germany
| | | | | | | |
Collapse
|
47
|
Tichauer KM, Holt RW, El-Ghussein F, Zhu Q, Dehghani H, Leblond F, Pogue BW. Imaging workflow and calibration for CT-guided time-domain fluorescence tomography. BIOMEDICAL OPTICS EXPRESS 2011; 2:3021-36. [PMID: 22076264 PMCID: PMC3207372 DOI: 10.1364/boe.2.003021] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Revised: 08/17/2011] [Accepted: 09/22/2011] [Indexed: 05/20/2023]
Abstract
In this study, several key optimization steps are outlined for a non-contact, time-correlated single photon counting small animal optical tomography system, using simultaneous collection of both fluorescence and transmittance data. The system is presented for time-domain image reconstruction in vivo, illustrating the sensitivity from single photon counting and the calibration steps needed to accurately process the data. In particular, laser time- and amplitude-referencing, detector and filter calibrations, and collection of a suitable instrument response function are all presented in the context of time-domain fluorescence tomography and a fully automated workflow is described. Preliminary phantom time-domain reconstructed images demonstrate the fidelity of the workflow for fluorescence tomography based on signal from multiple time gates.
Collapse
Affiliation(s)
- Kenneth M. Tichauer
- Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, NH 03755, USA
| | - Robert W. Holt
- Department of Physics and Astronomy, Dartmouth College, NH 03755, USA
| | - Fadi El-Ghussein
- Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, NH 03755, USA
| | - Qun Zhu
- School of Computer Science, University of Birmingham, Birmingham, B15 2TT, UK
| | - Hamid Dehghani
- School of Computer Science, University of Birmingham, Birmingham, B15 2TT, UK
| | - Frederic Leblond
- Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, NH 03755, USA
| | - Brian W. Pogue
- Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, NH 03755, USA
- Department of Physics and Astronomy, Dartmouth College, NH 03755, USA
| |
Collapse
|
48
|
Zhang B, Cao X, Liu F, Liu X, Wang X, Bai J. Early-photon fluorescence tomography of a heterogeneous mouse model with the telegraph equation. APPLIED OPTICS 2011; 50:5397-5407. [PMID: 22016206 DOI: 10.1364/ao.50.005397] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this study, we investigate the performance of early-photon fluorescence tomography based on a heterogeneous mouse model. The telegraph equation is used to accurately describe the propagation of light in tissues at short times. The optimal time gate for early photons is determined by singular value analysis at first. Then, fluorescent targets located in different organs of the mouse model are investigated. The simulation results demonstrate that the reconstructed tomographic images based on early photons yield improvement in spatial resolution and quantification than the quasi-CW measurements. Meanwhile, compared with the homogeneous model, the use of the heterogeneous model can improve the accuracy of fluorescence distribution and quantification in early-photon fluorescence tomography.
Collapse
Affiliation(s)
- Bin Zhang
- Department of Biomedical Engineering, Tsinghua University, Beijing, China
| | | | | | | | | | | |
Collapse
|
49
|
Lin Y, Ghijsen MT, Gao H, Liu N, Nalcioglu O, Gulsen G. A photo-multiplier tube-based hybrid MRI and frequency domain fluorescence tomography system for small animal imaging. Phys Med Biol 2011; 56:4731-47. [PMID: 21753235 PMCID: PMC3961472 DOI: 10.1088/0031-9155/56/15/007] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Fluorescence tomography (FT) is a promising molecular imaging technique that can spatially resolve both fluorophore concentration and lifetime parameters. However, recovered fluorophore parameters highly depend on the size and depth of the object due to the ill-posedness of the FT inverse problem. Structural a priori information from another high spatial resolution imaging modality has been demonstrated to significantly improve FT reconstruction accuracy. In this study, we have constructed a combined magnetic resonance imaging (MRI) and FT system for small animal imaging. A photo-multiplier tube is used as the detector to acquire frequency domain FT measurements. This is the first MR-compatible time-resolved FT system that can reconstruct both fluorescence concentration and lifetime maps simultaneously. The performance of the hybrid system is evaluated with phantom studies. Two different fluorophores, indocyanine green and 3-3' diethylthiatricarbocyanine iodide, which have similar excitation and emission spectra but different lifetimes, are utilized. The fluorescence concentration and lifetime maps are both reconstructed with and without the structural a priori information obtained from MRI for comparison. We show that the hybrid system can accurately recover both fluorescence intensity and lifetime within 10% error for two 4.2 mm-diameter cylindrical objects embedded in a 38 mm-diameter cylindrical phantom when MRI structural a priori information is utilized.
Collapse
Affiliation(s)
- Y Lin
- Tu and Yuen Center for Functional Onco Imaging, University of California, Irvine, CA, 92697, USA
| | - M T Ghijsen
- Tu and Yuen Center for Functional Onco Imaging, University of California, Irvine, CA, 92697, USA
| | - H Gao
- Department of Mathematics, University of California, Los Angeles, CA 90095, USA
| | - N Liu
- Tu and Yuen Center for Functional Onco Imaging, University of California, Irvine, CA, 92697, USA
| | - O Nalcioglu
- Tu and Yuen Center for Functional Onco Imaging, University of California, Irvine, CA, 92697, USA
- Department of Cogno-Mechatronics Engineering, Pusan National University, Pusan, Korea
| | - G Gulsen
- Tu and Yuen Center for Functional Onco Imaging, University of California, Irvine, CA, 92697, USA
| |
Collapse
|
50
|
Xin Liu, Xiaolian Guo, Fei Liu, Yi Zhang, Hui Zhang, Guangshu Hu, Jing Bai. Imaging of Indocyanine Green Perfusion in Mouse Liver With Fluorescence Diffuse Optical Tomography. IEEE Trans Biomed Eng 2011. [DOI: 10.1109/tbme.2011.2135858] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|