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Liu S, Wei W, Wang J, Chen T. Theranostic applications of selenium nanomedicines against lung cancer. J Nanobiotechnology 2023; 21:96. [PMID: 36935493 PMCID: PMC10026460 DOI: 10.1186/s12951-023-01825-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Accepted: 02/18/2023] [Indexed: 03/21/2023] Open
Abstract
The incidence and mortality rates of lung cancer are among the highest in the world. Traditional treatment methods include surgery, chemotherapy, and radiotherapy. Although rapid progress has been achieved in the past decade, treatment limitations remain. It is therefore imperative to identify safer and more effective therapeutic methods, and research is currently being conducted to identify more efficient and less harmful drugs. In recent years, the discovery of antitumor drugs based on the essential trace element selenium (Se) has provided good prospects for lung cancer treatments. In particular, compared to inorganic Se (Inorg-Se) and organic Se (Org-Se), Se nanomedicine (Se nanoparticles; SeNPs) shows much higher bioavailability and antioxidant activity and lower toxicity. SeNPs can also be used as a drug delivery carrier to better regulate protein and DNA biosynthesis and protein kinase C activity, thus playing a role in inhibiting cancer cell proliferation. SeNPs can also effectively activate antigen-presenting cells to stimulate cell immunity, exert regulatory effects on innate and regulatory immunity, and enhance lung cancer immunotherapy. This review summarizes the application of Se-based species and materials in lung cancer diagnosis, including fluorescence, MR, CT, photoacoustic imaging and other diagnostic methods, as well as treatments, including direct killing, radiosensitization, chemotherapeutic sensitization, photothermodynamics, and enhanced immunotherapy. In addition, the application prospects and challenges of Se-based drugs in lung cancer are examined, as well as their forecasted future clinical applications and sustainable development.
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Affiliation(s)
- Shaowei Liu
- Pulmonary and Critical Care Medicine, Guangzhou Institute of Respiratory Health, National Clinical Research Center for Respiratory Disease, National Center for Respiratory Medicine, State Key Laboratory of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510120, China
| | - Weifeng Wei
- Pulmonary and Critical Care Medicine, Guangzhou Institute of Respiratory Health, National Clinical Research Center for Respiratory Disease, National Center for Respiratory Medicine, State Key Laboratory of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510120, China
| | - Jinlin Wang
- Pulmonary and Critical Care Medicine, Guangzhou Institute of Respiratory Health, National Clinical Research Center for Respiratory Disease, National Center for Respiratory Medicine, State Key Laboratory of Respiratory Diseases, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510120, China.
| | - Tianfeng Chen
- College of Chemistry and Materials Science, Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou, 510632, China.
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2
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Patel R, Mowery YM, Qi Y, Bassil AM, Holbrook M, Xu ES, Hong CS, Himes JE, Williams NT, Everitt J, Ma Y, Luo L, Selitsky SR, Modliszewski JL, Gao J, Jung SH, Kirsch DG, Badea CT. Neoadjuvant Radiation Therapy and Surgery Improves Metastasis-Free Survival over Surgery Alone in a Primary Mouse Model of Soft Tissue Sarcoma. Mol Cancer Ther 2023; 22:112-122. [PMID: 36162051 PMCID: PMC9812921 DOI: 10.1158/1535-7163.mct-21-0991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 06/28/2022] [Accepted: 09/20/2022] [Indexed: 02/03/2023]
Abstract
This study aims to investigate whether adding neoadjuvant radiotherapy (RT), anti-programmed cell death protein-1 (PD-1) antibody (anti-PD-1), or RT + anti-PD-1 to surgical resection improves disease-free survival for mice with soft tissue sarcomas (STS). We generated a high mutational load primary mouse model of STS by intramuscular injection of adenovirus expressing Cas9 and guide RNA targeting Trp53 and intramuscular injection of 3-methylcholanthrene (MCA) into the gastrocnemius muscle of wild-type mice (p53/MCA model). We randomized tumor-bearing mice to receive isotype control or anti-PD-1 antibody with or without radiotherapy (20 Gy), followed by hind limb amputation. We used micro-CT to detect lung metastases with high spatial resolution, which was confirmed by histology. We investigated whether sarcoma metastasis was regulated by immunosurveillance by lymphocytes or tumor cell-intrinsic mechanisms. Compared with surgery with isotype control antibody, the combination of anti-PD-1, radiotherapy, and surgery improved local recurrence-free survival (P = 0.035) and disease-free survival (P = 0.005), but not metastasis-free survival. Mice treated with radiotherapy, but not anti-PD-1, showed significantly improved local recurrence-free survival and metastasis-free survival over surgery alone (P = 0.043 and P = 0.007, respectively). The overall metastasis rate was low (∼12%) in the p53/MCA sarcoma model, which limited the power to detect further improvement in metastasis-free survival with addition of anti-PD-1 therapy. Tail vein injections of sarcoma cells into immunocompetent mice suggested that impaired metastasis was due to inability of sarcoma cells to grow in the lungs rather than a consequence of immunosurveillance. In conclusion, neoadjuvant radiotherapy improves metastasis-free survival after surgery in a primary model of STS.
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Affiliation(s)
- Rutulkumar Patel
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27708 USA
| | - Yvonne M. Mowery
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27708 USA,Department of Head and Neck Surgery & Communication Sciences, Duke University Medical Center, Durham, NC 27710
| | - Yi Qi
- Department of Radiology, Duke University Medical Center, Durham, NC 27710
| | - Alex M. Bassil
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27708 USA
| | - Matt Holbrook
- Department of Radiology, Duke University Medical Center, Durham, NC 27710
| | - Eric S. Xu
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27708 USA
| | - Cierra S. Hong
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27708 USA
| | - Jonathon E. Himes
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27708 USA
| | - Nerissa T. Williams
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27708 USA
| | - Jeffrey Everitt
- Department of Pathology, Duke University School of Medicine, Durham, NC 27710
| | - Yan Ma
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27708 USA
| | - Lixia Luo
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27708 USA
| | | | | | - Junheng Gao
- Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC
| | - Sin-Ho Jung
- Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC
| | - David G. Kirsch
- Department of Radiation Oncology, Duke University School of Medicine, Durham, NC 27708 USA,Department of Pharmacology & Cancer Biology, Duke University School of Medicine, Durham, NC 27710
| | - Cristian T. Badea
- Department of Radiology, Duke University Medical Center, Durham, NC 27710
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3
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Ford NL, Lee I, Hwangbo J, Tam A, Sin DD. In vivo measurements of lung function using respiratory-gated micro-computed tomography in a smoke-exposure model of chronic obstructive pulmonary disease. J Med Imaging (Bellingham) 2023; 10:016002. [PMID: 36818545 PMCID: PMC9932522 DOI: 10.1117/1.jmi.10.1.016002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 01/23/2023] [Indexed: 02/18/2023] Open
Abstract
Purpose We hypothesize that in vivo respiratory-gated micro computed tomography (micro-CT) imaging can noninvasively provide structural and functional information about the lungs in a cigarette-exposure model of chronic obstructive pulmonary disease in mice. Approach Female C57BL/6 mice were exposed to cigarette smoke or ambient air for 1, 3, or 6 months. Each mouse received a respiratory-gated micro-CT scan at baseline and another scan following the exposure period, while anaesthetized and free-breathing. Images were obtained representing end-expiration and peak inspiration, and measurements were performed to characterize the lung structure and compute functional metrics. Following the final micro-CT session, the mice were euthanized and the lungs prepared for histology. Results Following 6 months of smoke-exposure, the mice exhibited larger increases in end-expiration lung volume and functional residual capacity, and a reduction in weight gain when compared with air-exposed mice. The histogram of CT numbers in the lung obtained during end-expiration also showed a shift to lower CT numbers following 6 months of smoke-exposure, indicating increased air content within the lungs. The metrics suggested air-trapping in the lung, which is consistent with emphysema. In the 3-month exposure group, only the reduction in weight gain was significant compared with the air-exposed group. Histological analysis confirmed that the 6-month smoke-exposed mice likely developed centrilobular emphysema as measured by the mean linear intercept. Conclusions Respiratory-gated micro-CT imaging of free-breathing mice at multiple respiratory phases is noninvasive and provides additional information about lung structure and function that complements postmortem techniques and could be used to monitor changes over time.
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Affiliation(s)
- Nancy L. Ford
- The University of British Columbia, Department of Oral Biological and Medical Sciences, Vancouver, British Columbia, Canada
- The University of British Columbia, Department of Physics and Astronomy, Vancouver, British Columbia, Canada
| | - Ian Lee
- The University of British Columbia, Department of Oral Biological and Medical Sciences, Vancouver, British Columbia, Canada
| | - Julia Hwangbo
- The University of British Columbia, Department of Oral Biological and Medical Sciences, Vancouver, British Columbia, Canada
| | - Anthony Tam
- The University of British Columbia, St. Paul’s Hospital, Centre for Heart Lung Innovation, Vancouver, British Columbia, Canada
| | - Don D. Sin
- The University of British Columbia, St. Paul’s Hospital, Centre for Heart Lung Innovation, Vancouver, British Columbia, Canada
- The University of British Columbia, Division of Respirology, Department of Medicine, Vancouver, British Columbia, Canada
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Shi Y, Li J, Li K, Zhang X, Chang P, Huang Z, Liu Y, Wang Y, Zhan Y, Cao X, Zhu S. Detector-trigger-based cardiac multiphase micro-CT imaging for small animals. JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2023; 31:1047-1066. [PMID: 37483057 DOI: 10.3233/xst-230034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
BACKGROUND Micro-computed tomography is important in cardiac imaging for preclinical small animal models, but motion artifacts may appear due to the rapid heart rates. To avoid influence of motion artifacts, the prospective ECG gating schemes based on an X-ray source trigger have been investigated. However, due to the lack of pulsed X-ray exposure modes, high-resolution micro-focus X-ray sources do not support source triggering in most cases. OBJECTIVE To develop a fast-cardiac multiphase acquisition strategy using prospective ECG gating for micro-focus X-ray tubes with a continuous emission mode. METHODS The proposed detector-trigger-based prospective ECG gating acquisition scheme (DTB-PG) triggers the X-ray detector at the R peak of ECG, and then collects multiple phase projections of the heart in one ECG cycle by sequence acquisition. Cardiac multiphase images are reconstructed after performing the same acquisition in all views. The feasibility of this strategy was verified in multiphase imaging experiments of a phantom with 150 ms motion period and a mouse heart on a micro-focus micro-CT system with continuous emission mode. RESULTS Using a high frame-rate CMOS detector, DTB-PG discriminates the positions of the motion phantom well in 10 different phases and enables to distinguish the changes in the cardiac volume of the mouse in different phases. The acquisition rate of DTB-PG is much faster than other prospective gating schemes as demonstrated by theoretical analysis. CONCLUSIONS DTB-PG combines the advantages of prospective ECG gating strategies and X-ray detector-trigger mode to suppress motion artifacts, achieve ultra-fast acquisition rates, and relax hardware limitations.
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Affiliation(s)
- Yu Shi
- School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi, China
- Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information & International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi, China
- Innovation Center for Advanced Medical Imaging and Intelligent Medicine, Guangzhou Institute of Technology, Xidian University, Guangzhou, Guangdong, China
| | - Juntao Li
- School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi, China
- Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information & International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi, China
- Innovation Center for Advanced Medical Imaging and Intelligent Medicine, Guangzhou Institute of Technology, Xidian University, Guangzhou, Guangdong, China
| | - Ke Li
- Xi'an Key Laboratory for Prevention and Treatment of Common Aging Diseases, Translational and Research Centre for Prevention and Therapy of Chronic Disease, Institute of Basic and Translational Medicine, Xi'an Medical University, Xi'an, China
| | - Xuexue Zhang
- School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi, China
- Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information & International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi, China
- Innovation Center for Advanced Medical Imaging and Intelligent Medicine, Guangzhou Institute of Technology, Xidian University, Guangzhou, Guangdong, China
| | - Peng Chang
- School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi, China
- Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information & International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi, China
| | - Zujian Huang
- School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi, China
- Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information & International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi, China
- Innovation Center for Advanced Medical Imaging and Intelligent Medicine, Guangzhou Institute of Technology, Xidian University, Guangzhou, Guangdong, China
| | - Yanyun Liu
- School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi, China
- Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information & International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi, China
- Innovation Center for Advanced Medical Imaging and Intelligent Medicine, Guangzhou Institute of Technology, Xidian University, Guangzhou, Guangdong, China
| | - Yihan Wang
- School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi, China
- Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information & International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi, China
- Innovation Center for Advanced Medical Imaging and Intelligent Medicine, Guangzhou Institute of Technology, Xidian University, Guangzhou, Guangdong, China
| | - Yonghua Zhan
- School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi, China
- Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information & International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi, China
| | - Xu Cao
- School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi, China
- Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information & International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi, China
- Innovation Center for Advanced Medical Imaging and Intelligent Medicine, Guangzhou Institute of Technology, Xidian University, Guangzhou, Guangdong, China
| | - Shouping Zhu
- School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi, China
- Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information & International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi, China
- Innovation Center for Advanced Medical Imaging and Intelligent Medicine, Guangzhou Institute of Technology, Xidian University, Guangzhou, Guangdong, China
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CArdiac and REspiratory adaptive Computed Tomography (CARE-CT): a proof-of-concept digital phantom study. Phys Eng Sci Med 2022; 45:1257-1271. [PMID: 36434201 DOI: 10.1007/s13246-022-01193-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 10/20/2022] [Indexed: 11/27/2022]
Abstract
Current respiratory 4DCT imaging for high-dose rate thoracic radiotherapy treatments are negatively affected by the complex interaction of cardiac and respiratory motion. We propose an imaging method to reduce artifacts caused by thoracic motion, CArdiac and REspiratory adaptive CT (CARE-CT), that monitors respiratory motion and ECG signals in real-time, triggering CT acquisition during combined cardiac and respiratory bins. Using a digital phantom, conventional 4DCT and CARE-CT acquisitions for nineteen patient-measured physiological traces were simulated. Ten respiratory bins were acquired for conventional 4DCT scans and ten respiratory bins during cardiac diastole were acquired for CARE-CT scans. Image artifacts were quantified for 10 common thoracic organs at risk (OAR) substructures using the differential normalized cross correlation between axial slices (ΔNCC), mean squared error (MSE) and sensitivity. For all images, on average, CARE-CT improved the ΔNCC for 18/19 and the MSE and sensitivity for all patient traces. The ΔNCC was reduced for all cardiac OARs (mean reduction 21%). The MSE was reduced for all OARs (mean reduction 36%). In the digital phantom study, the average scan time was increased from 1.8 ± 0.4 min to 7.5 ± 2.2 min with a reduction in average beam on time from 98 ± 28 s to 45 s using CARE-CT compared to conventional 4DCT. The proof-of-concept study indicates the potential for CARE-CT to image the thorax in real-time during the cardiac and respiratory cycle simultaneously, to reduce image artifacts for common thoracic OARs.
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6
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Thamm M, Rosenhain S, Leonardic K, Höfter A, Kiessling F, Osl F, Pöschinger T, Gremse F. Intrinsic Respiratory Gating for Simultaneous Multi-Mouse μCT Imaging to Assess Liver Tumors. Front Med (Lausanne) 2022; 9:878966. [PMID: 35872758 PMCID: PMC9299429 DOI: 10.3389/fmed.2022.878966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 06/08/2022] [Indexed: 11/18/2022] Open
Abstract
Small animal micro computed tomography (μCT) is an important tool in cancer research and is used to quantify liver and lung tumors. A type of cancer that is intensively investigated with μCT is hepatocellular carcinoma (HCC). μCT scans acquire projections from different angles of the gantry which rotates X-ray source and detector around the animal. Motion of the animal causes inconsistencies between the projections which lead to artifacts in the resulting image. This is problematic in HCC research, where respiratory motion affects the image quality by causing hypodense intensity at the liver edge and smearing out small structures such as tumors. Dealing with respiratory motion is particularly difficult in a high throughput setting when multiple mice are scanned together and projection removal by retrospective respiratory gating may compromise image quality and dose efficiency. In mice, inhalation anesthesia leads to a regular respiration with short gasps and long phases of negligible motion. Using this effect and an iterative reconstruction which can cope with missing angles, we discard the relatively few projections in which the gasping motion occurs. Moreover, since gated acquisition, i.e., acquiring multiple projections from a single gantry angle is not a requirement, this method can be applied to existing scans. We applied our method in a high throughput setting in which four mice with HCC tumors were scanned simultaneously in a multi-mouse bed. To establish a ground truth, we manually selected projections with visible respiratory motion. Our automated intrinsic breathing projection selection achieved an accordance of 97% with manual selection. We reconstructed volumetric images and demonstrated that our intrinsic gating method significantly reduces the hypodense depiction at the cranial liver edge and improves the detectability of small tumors. Furthermore, we show that projection removal in a four mice scan discards only 7.5% more projections than in a single-mouse setting, i.e., four mouse scanning does not substantially compromise dose efficiency or image quality. To the best of our knowledge, no comparable method that combines multi-mouse scans for high throughput, intrinsic respiratory gating, and an available iterative reconstruction has been described for liver tumor imaging before.
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Affiliation(s)
- Mirko Thamm
- Experimental Molecular Imaging, RWTH Aachen University, Aachen, Germany
- Gremse-IT GmbH, Aachen, Germany
| | | | | | | | - Fabian Kiessling
- Experimental Molecular Imaging, RWTH Aachen University, Aachen, Germany
- Fraunhofer Institute for Digital Medicine MEVIS, Bremen, Germany
| | - Franz Osl
- Discovery Pharmacology, Pharma Research and Early Development (pRED), Roche Innovation Center Munich, Penzberg, Germany
| | - Thomas Pöschinger
- Discovery Pharmacology, Pharma Research and Early Development (pRED), Roche Innovation Center Munich, Penzberg, Germany
| | - Felix Gremse
- Experimental Molecular Imaging, RWTH Aachen University, Aachen, Germany
- Gremse-IT GmbH, Aachen, Germany
- *Correspondence: Felix Gremse
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Rickard AG, Zhuang M, DeRosa CA, Dewhirst MW, Fraser CL, Palmer GM. Quantifying the effects of anesthesia on intracellular oxygen via low-cost portable microscopy using dual-emissive nanoparticles. BIOMEDICAL OPTICS EXPRESS 2022; 13:3869-3881. [PMID: 35991919 PMCID: PMC9352295 DOI: 10.1364/boe.456125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 05/13/2022] [Accepted: 05/17/2022] [Indexed: 06/15/2023]
Abstract
Intracellular oxygenation is an important parameter for numerous biological studies. While there are a variety of methods available for acquiring in vivo measurements of oxygenation in animal models, most are dependent on indirect oxygen measurements, restraints, or anesthetization. A portable microscope system using a Raspberry Pi computer and Pi Camera was developed for attaching to murine dorsal window chambers. Dual-emissive boron nanoparticles were used as an oxygen-sensing probe while mice were imaged in awake and anesthetized states. The portable microscope system avoids altered in vivo measurements due to anesthesia or restraints while enabling increased continual acquisition durations.
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Affiliation(s)
- Ashlyn G. Rickard
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, USA
| | - Meng Zhuang
- Department of Chemistry, University of Virginia, Charlottesville, VA, USA
| | | | - Mark W. Dewhirst
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, USA
| | | | - Gregory M. Palmer
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, USA
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Balasubramanian SL, Krishnamurthi G. X-ray scintillator lens-coupled with CMOS camera for pre-clinical cardiac vascular imaging—A feasibility study. PLoS One 2022; 17:e0262913. [PMID: 35148354 PMCID: PMC8836319 DOI: 10.1371/journal.pone.0262913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 01/07/2022] [Indexed: 11/23/2022] Open
Abstract
We present the design and characterization of an X-ray imaging system consisting of an off-the-shelf CMOS sensor optically coupled to a CsI scintillator. The camera can perform both high-resolution and functional cardiac imaging. High-resolution 3D imaging requires microfocus X-ray tubes and expensive detectors, while pre-clinical functional cardiac imaging requires high flux pulsed (clinical) X-ray tubes and high-end cameras. Our work describes an X-ray camera, namely an “optically coupled X-ray(OCX) detector,” used for both the aforementioned applications with no change in the specifications. We constructed the imaging detector with two different CMOS optical imaging cameras called CMOS sensors, 1.A monochrome CMOS sensor coupled with an f1.4 lens and 2.an RGB CMOS sensor coupled with an f0.95 prime lens. The imaging system consisted of our X-ray camera, micro-focus X-ray source (50kVp and 1mA), and a rotary stage controlled from a personal computer (PC) and LabVIEW interface. The detective quantum efficiency (DQE) of the imaging system(monochrome) estimated using a cascaded linear model was 17% at 10 lp/mm. The system modulation transfer function (MTF) and the noise power spectrum (NPS) were inputs to the DQE estimation. Because of the RGB camera’s low quantum efficiency (QE), the OCX detector DQE was 19% at 5 lp/mm. The contrast to noise ratio (CNR) at different frame rates was studied using the capillary tubes filled with various dilutions of iodinated contrast agents. In-vivo cardiac angiography demonstrated that blood vessels of the order of 100 microns or above were visible at 40 frames per second despite the low X-ray flux. For high-resolution 3D imaging, the system was characterized by imaging a cylindrical micro-CT contrast phantom and comparing it against images from a commercial scanner.
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Affiliation(s)
| | - Ganapathy Krishnamurthi
- Department of Engineering Design, Indian Institute of Technology-Madras, Chennai, TamilNadu, India
- * E-mail:
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9
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Coppola A, Zorzetto G, Piacentino F, Bettoni V, Pastore I, Marra P, Perani L, Esposito A, De Cobelli F, Carcano G, Fontana F, Fiorina P, Venturini M. Imaging in experimental models of diabetes. Acta Diabetol 2022; 59:147-161. [PMID: 34779949 DOI: 10.1007/s00592-021-01826-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/30/2021] [Indexed: 12/01/2022]
Abstract
Translational medicine, experimental medicine and experimental animal models, in particular mice and rats, represent a multidisciplinary field that has made it possible to achieve, in the last decades, important scientific progress. In this review, we have summarized the most frequently used imaging animal models, such as ultrasound (US), micro-CT, MRI and the optical imaging methods, and their main implications in diagnostic and therapeutic fields, with a particular focus on diabetes mellitus, a multifactorial disease extremely widespread among the general population.
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Affiliation(s)
- Andrea Coppola
- Diagnostic and Interventional Radiology Unit, ASST Settelaghi, Varese, Italy.
| | | | - Filippo Piacentino
- Diagnostic and Interventional Radiology Unit, ASST Settelaghi, Varese, Italy
- Insubria University, Varese, Italy
| | - Valeria Bettoni
- Diagnostic and Interventional Radiology Unit, ASST Settelaghi, Varese, Italy
| | - Ida Pastore
- Division of Endocrinology, ASST Fatebenefratelli-Sacco, Milan, Italy
| | - Paolo Marra
- Department of Diagnostic Radiology, Giovanni XXIII Hospital, Milano-Bicocca University, Bergamo, Italy
| | - Laura Perani
- Experimental Imaging Center, San Raffaele Scientific Institute, Milan, Italy
| | - Antonio Esposito
- Experimental Imaging Center, San Raffaele Scientific Institute, Milan, Italy
- Radiology Unit, San Raffaele Scientific Institute, San Raffaele Vita-Salute University, Milan, Italy
| | - Francesco De Cobelli
- Radiology Unit, San Raffaele Scientific Institute, San Raffaele Vita-Salute University, Milan, Italy
| | - Giulio Carcano
- Insubria University, Varese, Italy
- General, Emergency, and Transplant Surgery Unit, ASST Settelaghi, Varese, Italy
| | - Federico Fontana
- Diagnostic and Interventional Radiology Unit, ASST Settelaghi, Varese, Italy
- Insubria University, Varese, Italy
| | - Paolo Fiorina
- International Center for T1D, Centro di Ricerca Pediatrica Romeo ed Enrica Invernizzi, Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università di Milano, Milan, Italy
- Nephrology Division, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Endocrinology Division, ASST Fatebenefratelli Sacco, Milan, Italy
| | - Massimo Venturini
- Diagnostic and Interventional Radiology Unit, ASST Settelaghi, Varese, Italy
- Insubria University, Varese, Italy
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Shoghi KI, Badea CT, Blocker SJ, Chenevert TL, Laforest R, Lewis MT, Luker GD, Manning HC, Marcus DS, Mowery YM, Pickup S, Richmond A, Ross BD, Vilgelm AE, Yankeelov TE, Zhou R. Co-Clinical Imaging Resource Program (CIRP): Bridging the Translational Divide to Advance Precision Medicine. ACTA ACUST UNITED AC 2021; 6:273-287. [PMID: 32879897 PMCID: PMC7442091 DOI: 10.18383/j.tom.2020.00023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The National Institutes of Health’s (National Cancer Institute) precision medicine initiative emphasizes the biological and molecular bases for cancer prevention and treatment. Importantly, it addresses the need for consistency in preclinical and clinical research. To overcome the translational gap in cancer treatment and prevention, the cancer research community has been transitioning toward using animal models that more fatefully recapitulate human tumor biology. There is a growing need to develop best practices in translational research, including imaging research, to better inform therapeutic choices and decision-making. Therefore, the National Cancer Institute has recently launched the Co-Clinical Imaging Research Resource Program (CIRP). Its overarching mission is to advance the practice of precision medicine by establishing consensus-based best practices for co-clinical imaging research by developing optimized state-of-the-art translational quantitative imaging methodologies to enable disease detection, risk stratification, and assessment/prediction of response to therapy. In this communication, we discuss our involvement in the CIRP, detailing key considerations including animal model selection, co-clinical study design, need for standardization of co-clinical instruments, and harmonization of preclinical and clinical quantitative imaging pipelines. An underlying emphasis in the program is to develop best practices toward reproducible, repeatable, and precise quantitative imaging biomarkers for use in translational cancer imaging and therapy. We will conclude with our thoughts on informatics needs to enable collaborative and open science research to advance precision medicine.
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Affiliation(s)
- Kooresh I Shoghi
- Department of Radiology, Washington University School of Medicine, St. Louis, MO
| | - Cristian T Badea
- Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC
| | - Stephanie J Blocker
- Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC
| | | | - Richard Laforest
- Department of Radiology, Washington University School of Medicine, St. Louis, MO
| | - Michael T Lewis
- Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX
| | - Gary D Luker
- Department of Radiology, University of Michigan, Ann Arbor, MI
| | - H Charles Manning
- Vanderbilt Center for Molecular Probes-Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN
| | - Daniel S Marcus
- Department of Radiology, Washington University School of Medicine, St. Louis, MO
| | - Yvonne M Mowery
- Department of Radiation Oncology, Duke University Medical Center, Durham, Durham, NC
| | - Stephen Pickup
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania.,Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA
| | - Ann Richmond
- Department of Pharmacology, Vanderbilt School of Medicine, Nashville, TN
| | - Brian D Ross
- Department of Radiology, University of Michigan, Ann Arbor, MI
| | - Anna E Vilgelm
- Department of Pathology, The Ohio State University, Columbus, OH
| | - Thomas E Yankeelov
- Departments of Biomedical Engineering, Diagnostic Medicine, and Oncology, Oden Institute for Computational Engineering and Sciences, Austin, TX; and.,Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX
| | - Rong Zhou
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania.,Abramson Cancer Center, University of Pennsylvania, Philadelphia, PA
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11
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Badea CT. Principles of Micro X-ray Computed Tomography. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00006-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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12
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Tielemans B, Dekoster K, Verleden SE, Sawall S, Leszczyński B, Laperre K, Vanstapel A, Verschakelen J, Kachelriess M, Verbeken E, Swoger J, Vande Velde G. From Mouse to Man and Back: Closing the Correlation Gap between Imaging and Histopathology for Lung Diseases. Diagnostics (Basel) 2020; 10:E636. [PMID: 32859103 PMCID: PMC7554749 DOI: 10.3390/diagnostics10090636] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/21/2020] [Accepted: 08/24/2020] [Indexed: 02/07/2023] Open
Abstract
Lung diseases such as fibrosis, asthma, cystic fibrosis, infection and cancer are life-threatening conditions that slowly deteriorate quality of life and for which our diagnostic power is high, but our knowledge on etiology and/or effective treatment options still contains important gaps. In the context of day-to-day practice, clinical and preclinical studies, clinicians and basic researchers team up and continuously strive to increase insights into lung disease progression, diagnostic and treatment options. To unravel disease processes and to test novel therapeutic approaches, investigators typically rely on end-stage procedures such as serum analysis, cyto-/chemokine profiles and selective tissue histology from animal models. These techniques are useful but provide only a snapshot of disease processes that are essentially dynamic in time and space. Technology allowing evaluation of live animals repeatedly is indispensable to gain a better insight into the dynamics of lung disease progression and treatment effects. Computed tomography (CT) is a clinical diagnostic imaging technique that can have enormous benefits in a research context too. Yet, the implementation of imaging techniques in laboratories lags behind. In this review we want to showcase the integrated approaches and novel developments in imaging, lung functional testing and pathological techniques that are used to assess, diagnose, quantify and treat lung disease and that may be employed in research on patients and animals. Imaging approaches result in often novel anatomical and functional biomarkers, resulting in many advantages, such as better insight in disease progression and a reduction in the numbers of animals necessary. We here showcase integrated assessment of lung disease with imaging and histopathological technologies, applied to the example of lung fibrosis. Better integration of clinical and preclinical imaging technologies with pathology will ultimately result in improved clinical translation of (therapy) study results.
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Affiliation(s)
- Birger Tielemans
- Department of Imaging and Pathology, KU Leuven, University of Leuven, 3000 Leuven, Belgium; (B.T.); (K.D.); (J.V.); (E.V.)
| | - Kaat Dekoster
- Department of Imaging and Pathology, KU Leuven, University of Leuven, 3000 Leuven, Belgium; (B.T.); (K.D.); (J.V.); (E.V.)
| | - Stijn E. Verleden
- Department of CHROMETA, BREATHE lab, KU Leuven, 3000 Leuven, Belgium; (S.E.V.); (A.V.)
| | - Stefan Sawall
- German Cancer Research Center (DKFZ), X-Ray Imaging and CT, Heidelberg University, 69117 Heidelberg, Germany; (S.S.); (M.K.)
| | - Bartosz Leszczyński
- Department of Medical Physics, M. Smoluchowski Institute of Physics, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 31-007 Kraków, Poland;
| | | | - Arno Vanstapel
- Department of CHROMETA, BREATHE lab, KU Leuven, 3000 Leuven, Belgium; (S.E.V.); (A.V.)
| | - Johny Verschakelen
- Department of Imaging and Pathology, KU Leuven, University of Leuven, 3000 Leuven, Belgium; (B.T.); (K.D.); (J.V.); (E.V.)
| | - Marc Kachelriess
- German Cancer Research Center (DKFZ), X-Ray Imaging and CT, Heidelberg University, 69117 Heidelberg, Germany; (S.S.); (M.K.)
| | - Erik Verbeken
- Department of Imaging and Pathology, KU Leuven, University of Leuven, 3000 Leuven, Belgium; (B.T.); (K.D.); (J.V.); (E.V.)
| | - Jim Swoger
- European Molecular Biology Laboratory (EMBL) Barcelona, 08003 Barcelona, Spain;
| | - Greetje Vande Velde
- Department of Imaging and Pathology, KU Leuven, University of Leuven, 3000 Leuven, Belgium; (B.T.); (K.D.); (J.V.); (E.V.)
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13
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Blocker SJ, Holbrook MD, Mowery YM, Sullivan DC, Badea CT. The impact of respiratory gating on improving volume measurement of murine lung tumors in micro-CT imaging. PLoS One 2020; 15:e0225019. [PMID: 32097413 PMCID: PMC7041814 DOI: 10.1371/journal.pone.0225019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 01/22/2020] [Indexed: 02/01/2023] Open
Abstract
Small animal imaging has become essential in evaluating new cancer therapies as they are translated from the preclinical to clinical domain. However, preclinical imaging faces unique challenges that emphasize the gap between mouse and man. One example is the difference in breathing patterns and breath-holding ability, which can dramatically affect tumor burden assessment in lung tissue. As part of a co-clinical trial studying immunotherapy and radiotherapy in sarcomas, we are using micro-CT of the lungs to detect and measure metastases as a metric of disease progression. To effectively utilize metastatic disease detection as a metric of progression, we have addressed the impact of respiratory gating during micro-CT acquisition on improving lung tumor detection and volume quantitation. Accuracy and precision of lung tumor measurements with and without respiratory gating were studied by performing experiments with in vivo images, simulations, and a pocket phantom. When performing test-retest studies in vivo, the variance in volume calculations was 5.9% in gated images and 15.8% in non-gated images, compared to 2.9% in post-mortem images. Sensitivity of detection was examined in images with simulated tumors, demonstrating that reliable sensitivity (true positive rate (TPR) ≥ 90%) was achievable down to 1.0 mm3 lesions with respiratory gating, but was limited to ≥ 8.0 mm3 in non-gated images. Finally, a clinically-inspired "pocket phantom" was used during in vivo mouse scanning to aid in refining and assessing the gating protocols. Application of respiratory gating techniques reduced variance of repeated volume measurements and significantly improved the accuracy of tumor volume quantitation in vivo.
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Affiliation(s)
- S. J. Blocker
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - M. D. Holbrook
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Y. M. Mowery
- Department of Radiation Oncology, Duke Cancer Institute, Durham, North Carolina, United States of America
| | - D. C. Sullivan
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - C. T. Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, North Carolina, United States of America
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14
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15
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Blocker SJ, Mowery YM, Holbrook MD, Qi Y, Kirsch DG, Johnson GA, Badea CT. Bridging the translational gap: Implementation of multimodal small animal imaging strategies for tumor burden assessment in a co-clinical trial. PLoS One 2019; 14:e0207555. [PMID: 30958825 PMCID: PMC6453461 DOI: 10.1371/journal.pone.0207555] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 03/13/2019] [Indexed: 12/17/2022] Open
Abstract
In designing co-clinical cancer studies, preclinical imaging brings unique challenges that emphasize the gap between man and mouse. Our group is developing quantitative imaging methods for the preclinical arm of a co-clinical trial studying immunotherapy and radiotherapy in a soft tissue sarcoma model. In line with treatment for patients enrolled in the clinical trial SU2C-SARC032, primary mouse sarcomas are imaged with multi-contrast micro-MRI (T1 weighted, T2 weighted, and T1 with contrast) before and after immune checkpoint inhibition and pre-operative radiation therapy. Similar to the patients, after surgery the mice will be screened for lung metastases with micro-CT using respiratory gating. A systems evaluation was undertaken to establish a quantitative baseline for both the MR and micro-CT systems against which others systems might be compared. We have constructed imaging protocols which provide clinically-relevant resolution and contrast in a genetically engineered mouse model of sarcoma. We have employed tools in 3D Slicer for semi-automated segmentation of both MR and micro-CT images to measure tumor volumes efficiently and reliably in a large number of animals. Assessment of tumor burden in the resulting images was precise, repeatable, and reproducible. Furthermore, we have implemented a publicly accessible platform for sharing imaging data collected during the study, as well as protocols, supporting information, and data analyses. In doing so, we aim to improve the clinical relevance of small animal imaging and begin establishing standards for preclinical imaging of tumors from the perspective of a co-clinical trial.
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Affiliation(s)
- S. J. Blocker
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States of America
| | - Y. M. Mowery
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, United States of America
| | - M. D. Holbrook
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States of America
| | - Y. Qi
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States of America
| | - D. G. Kirsch
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC, United States of America
- Department of Pharmacology & Cancer Biology, Duke University Medical Center, Durham, NC, United States of America
| | - G. A. Johnson
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States of America
| | - C. T. Badea
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC, United States of America
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16
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Mannheim JG, Kara F, Doorduin J, Fuchs K, Reischl G, Liang S, Verhoye M, Gremse F, Mezzanotte L, Huisman MC. Standardization of Small Animal Imaging-Current Status and Future Prospects. Mol Imaging Biol 2019; 20:716-731. [PMID: 28971332 DOI: 10.1007/s11307-017-1126-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The benefit of small animal imaging is directly linked to the validity and reliability of the collected data. If the data (regardless of the modality used) are not reproducible and/or reliable, then the outcome of the data is rather questionable. Therefore, standardization of the use of small animal imaging equipment, as well as of animal handling in general, is of paramount importance. In a recent paper, guidance for efficient small animal imaging quality control was offered and discussed, among others, the use of phantoms in setting up a quality control program (Osborne et al. 2016). The same phantoms can be used to standardize image quality parameters for multi-center studies or multi-scanners within center studies. In animal experiments, the additional complexity due to animal handling needs to be addressed to ensure standardized imaging procedures. In this review, we will address the current status of standardization in preclinical imaging, as well as potential benefits from increased levels of standardization.
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Affiliation(s)
- Julia G Mannheim
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Roentgenweg 13, 72076, Tuebingen, Germany.
| | - Firat Kara
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
| | - Janine Doorduin
- Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Kerstin Fuchs
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Roentgenweg 13, 72076, Tuebingen, Germany
| | - Gerald Reischl
- Werner Siemens Imaging Center, Department of Preclinical Imaging and Radiopharmacy, Eberhard Karls University Tuebingen, Roentgenweg 13, 72076, Tuebingen, Germany
| | - Sayuan Liang
- Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium
| | | | - Felix Gremse
- Institute for Experimental Molecular Imaging, RWTH Aachen University Clinic, Aachen, Germany
| | - Laura Mezzanotte
- Optical Molecular Imaging, Department of Radiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Marc C Huisman
- Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
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17
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Ford NL, Tan S, Deman P. An investigation of radiation damage in rat lungs following dual-energy micro-CT imaging. Biomed Phys Eng Express 2019. [DOI: 10.1088/2057-1976/aaf240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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18
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Gabrielson K, Maronpot R, Monette S, Mlynarczyk C, Ramot Y, Nyska A, Sysa-Shah P. In Vivo Imaging With Confirmation by Histopathology for Increased Rigor and Reproducibility in Translational Research: A Review of Examples, Options, and Resources. ILAR J 2018; 59:80-98. [PMID: 30541081 PMCID: PMC6645176 DOI: 10.1093/ilar/ily010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 07/18/2018] [Indexed: 12/13/2022] Open
Abstract
Preclinical noninvasive imaging can be an indispensable tool for studying animal models of disease. In vivo imaging to assess anatomical, functional, and molecular features requires verification by a comparison to the macroscopic and microscopic morphological features, since all noninvasive in vivo imaging methods have much lower resolution than standard histopathology. Comprehensive pathological evaluation of the animal model is underutilized; yet, many institutions have veterinary or human pathologists with necessary comparative pathology expertise. By performing a rigorous comparison to gross or histopathology for image interpretation, these trained individuals can assist scientists with the development of the animal model, experimental design, and evaluation of the in vivo imaging data. These imaging and pathology corroboration studies undoubtedly increase scientific rigor and reproducibility in descriptive and hypothesis-driven research. A review of case examples including ultrasound, nuclear, optical, and MRI is provided to illustrate how a wide range of imaging modalities data can be confirmed by gross or microscopic pathology. This image confirmation and authentication will improve characterization of the model and may contribute to decreasing costs and number of animals used and to more rapid translation from preclinical animal model to the clinic.
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Affiliation(s)
- Kathleen Gabrielson
- Departments of Molecular and Comparative Pathology and Pathology School of Medicine, Environmental Health Engineering Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland
| | | | - Sébastien Monette
- Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, The Rockefeller University, Weill Cornell Medicine, New York, New York
| | - Coraline Mlynarczyk
- Department of Medicine, Division of Hematology & Medical Oncology and the Meyer Cancer Center, Weill Cornell Medicine, New York, New York
| | - Yuval Ramot
- Department of Dermatology, Hadassah—Hebrew University Medical Center, Kiryat Hadassah, Jerusalem, Israel
| | - Abraham Nyska
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel and Toxicologic Pathology, Timrat, Israel
| | - Polina Sysa-Shah
- Department of Radiology, Miller Research Building Molecular Imaging Service Center, Johns Hopkins University, Baltimore, Maryland
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19
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Frelin AM, Beaudouin V, Le Deroff C, Roger T. Implementation and evaluation of respiratory gating in small animal radiotherapy. Phys Med Biol 2018; 63:215024. [PMID: 30375369 DOI: 10.1088/1361-6560/aae760] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Major advance was done in preclinical radiotherapy thanks to the development of image guided micro-irradiator. Nevertheless, some applications still can benefit of improvements, such as the irradiation of mobile tumors. This preclinical radiotherapy case presents increased difficulties compared to clinical practice because of the waveform of small animals breathing cycle, its frequency and amplitude. To answer this issue, we developed a specific beam shutter and implemented respiratory gating on the X-RAD 225Cx preclinical irradiator. In the first step of this study, the shutter was accurately characterized. Opening and closing speed of 1.28 and 0.33 mm ms-1 were respectively measured, and a transmission of 0.7% of the beam was measured with the shutter fully closed. Beam-on times were also determined for various gating parameters and highlighted a difference of 57 ms between the beam delivery duration and the gate width. This discrepancy was compensated during the respiratory monitoring adjustment. In a second step, a respiratory protocol was evaluated with two vertical beams of 2.5 and 5 mm diameters, for motion amplitudes ranging from 0.5 to 4 mm. This evaluation demonstrated the effectiveness of our set up to perform motion compensation for amplitude as small as 0.5 mm despite a dose gradient of 1.47 cGy mm-1 observed with the 5 mm irradiation field, due to the shutter opening and closing durations. We also investigated the efficiency of a scintillating fiber dosimeter, adapted to small beams and providing real-time dose rate measurements. This detector showed very good performances to detect motion in small irradiation fields and would be very suitable to monitor the number of delivered gates until the planned delivered dose is achieved. This study presented a new respiratory gating set up and showed that very efficient motion compensation could be achieved in small animal radiotherapy.
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Affiliation(s)
- A-M Frelin
- Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Boulevard Henri Becquerel, 14076 Caen, France. Advanced Resource Centre for Hadrontherapy in Europe (ARCHADE) Program, Caen, France
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20
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D'Eurydice MN, Arns CH, Arns JY, Armstrong RT. Dynamic imaging of multiphase flow through porous media using 4D cumulative reconstruction. J Microsc 2018; 272:12-24. [PMID: 29971773 DOI: 10.1111/jmi.12728] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 06/06/2018] [Indexed: 11/30/2022]
Abstract
This paper introduces an original application on reconstruction strategies for X-ray computed microtomography, enabling the observation of time-dependent changes that occur during multiphase flow. In general, by sparsely collecting radiographs, the reconstruction of the object is compromised. Optimizations can be achieved by combining specific characteristics of the dynamics with the acquisition. Herein, the proposed method relies on short random intervals in which no drastic changes occur in the sample to acquire as many radiographs as possible that constitute a reconstructible data set. As these intervals are unpredictable, the method tries to guarantee that the collected radiograph data during these specific intervals are enough to recover useful information about the dynamics. Simulations of a percolating fluid in a digital rock are used to replicate an X-ray computed microtomography experiment to test the proposed method. The results demonstrate the potential of the proposed strategy for imaging multiphase flow in porous media and how data collected during distinct events can be combined to enhance the reconstruction of frames of the percolation process.
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Affiliation(s)
- M N D'Eurydice
- School of Minerals and Energy Resources Engineering, University of New South Wales, Kensington, NSW, Australia.,Source Crafting Limited, Wellington, New Zealand
| | - C H Arns
- School of Minerals and Energy Resources Engineering, University of New South Wales, Kensington, NSW, Australia
| | - J-Y Arns
- School of Minerals and Energy Resources Engineering, University of New South Wales, Kensington, NSW, Australia
| | - R T Armstrong
- School of Minerals and Energy Resources Engineering, University of New South Wales, Kensington, NSW, Australia
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21
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Maronpot RR, Nyska A, Troth SP, Gabrielson K, Sysa-Shah P, Kalchenko V, Kuznetsov Y, Harmelin A, Schiffenbauer YS, Bonnel D, Stauber J, Ramot Y. Regulatory Forum Opinion Piece*: Imaging Applications in Toxicologic Pathology-Recommendations for Use in Regulated Nonclinical Toxicity Studies. Toxicol Pathol 2018. [PMID: 28641506 DOI: 10.1177/0192623317710014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Available imaging systems for use in preclinical toxicology studies increasingly show utility as important tools in the toxicologic pathologist's armamentarium, permit longitudinal evaluation of functional and morphological changes in tissues, and provide important information such as organ and lesion volume not obtained by conventional toxicology study parameters. Representative examples of practical imaging applications in toxicology research and preclinical studies are presented for ultrasound, positron emission tomography/single-photon emission computed tomography, optical, magnetic resonance imaging, and matrix-assisted laser desorption ionization-imaging mass spectrometry imaging. Some of the challenges for making imaging systems good laboratory practice-compliant for regulatory submission are presented. Use of imaging data on a case-by-case basis as part of safety evaluation in regulatory submissions is encouraged.
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Affiliation(s)
| | - Abraham Nyska
- 2 Toxicologic Pathology, Sackler School of Medicine, Tel Aviv University, Timrat, Israel
| | - Sean P Troth
- 3 Merck & Co., Inc., West Point, Pennsylvania, USA
| | - Kathleen Gabrielson
- 4 Department of Molecular and Comparative Pathobiology, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Polina Sysa-Shah
- 4 Department of Molecular and Comparative Pathobiology, School of Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Vyacheslav Kalchenko
- 5 Department of Veterinary Resources, Weizmann Institute of Science, Rehovot, Israel
| | - Yuri Kuznetsov
- 5 Department of Veterinary Resources, Weizmann Institute of Science, Rehovot, Israel
| | - Alon Harmelin
- 5 Department of Veterinary Resources, Weizmann Institute of Science, Rehovot, Israel
| | | | | | | | - Yuval Ramot
- 8 Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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22
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Gallastegui A, Cheung J, Southard T, Hume KR. Volumetric and linear measurements of lung tumor burden from non-gated micro-CT imaging correlate with histological analysis in a genetically engineered mouse model of non-small cell lung cancer. Lab Anim 2018; 52:457-469. [PMID: 29436921 DOI: 10.1177/0023677218756457] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
In vivo micro-computed tomography (CT) imaging allows longitudinal studies of pulmonary neoplasms in genetically engineered mouse models. Respiratory gating increases the accuracy of lung tumor measurements but lengthens anesthesia time in animals that may be at increased risk for complications. We hypothesized that semiautomated, volumetric, and linear tumor measurements performed in micro-CT images from non-gated scans would have correlation with histological findings. Primary lung tumors were induced in eight FVB mice with two transgenes (FVB/N-Tg(tetO-Kras2)12Hev/J; FVB.Cg-Tg(Scgb1a1-rtTA)1Jaw/J). Non-gated micro-CT scans were performed and the lungs were subsequently harvested. In the acquired micro-CT scans, measurements of all identified tumors were determined using the following methods: semiautomated three-dimensional (3D) volume, ellipsoid volume, Response Evaluation Criteria in Solid Tumors (RECIST; sum of largest axial (i.e., transverse) diameter from five tumors), sum of largest axial diameters from all tumors (modified RECIST), and average axial diameter. For histological analysis, all five lung lobes were analyzed and the tumor area was summed from measurements made on five histological sections that were 300 µm apart from each other (covering a total depth of 1200 µm). All micro-CT measurement methods had very strong correlation with histological tumor burden (Pearson's correlation coefficient, 0.87 ( p = 0.0053) -0.98 ( p < 0.0001)). The only methods found to have different correlations were the semiautomated 3D method and the RECIST method (Williams' test for dependent overlapping correlations, p = 0.013). Our results suggest quantification of lung tumor burden from non-gated micro-CT imaging will reflect histological differences between mice and can therefore be used for between-group comparisons or when concerns about systemic health of research animals may limit lengthy anesthetic procedures.
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Affiliation(s)
- Aitor Gallastegui
- 1 Department of Small Animal Clinical Sciences, University of Florida College of Veterinary Medicine, USA
| | - James Cheung
- 2 Department of Clinical Sciences, Cornell University College of Veterinary Medicine, USA
| | - Teresa Southard
- 3 Department of Biomedical Sciences, Cornell University College of Veterinary Medicine, USA
| | - Kelly R Hume
- 2 Department of Clinical Sciences, Cornell University College of Veterinary Medicine, USA
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23
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Ford NL, McCaig L, Jeklin A, Lewis JF, Veldhuizen RAW, Holdsworth DW, Drangova M. A respiratory-gated micro-CT comparison of respiratory patterns in free-breathing and mechanically ventilated rats. Physiol Rep 2017; 5:5/2/e13074. [PMID: 28100723 PMCID: PMC5269405 DOI: 10.14814/phy2.13074] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 11/14/2016] [Accepted: 11/19/2016] [Indexed: 11/24/2022] Open
Abstract
In this study, we aim to quantify the differences in lung metrics measured in free-breathing and mechanically ventilated rodents using respiratory-gated micro-computed tomography. Healthy male Sprague-Dawley rats were anesthetized with ketamine/xylazine and scanned with a retrospective respiratory gating protocol on a GE Locus Ultra micro-CT scanner. Each animal was scanned while free-breathing, then intubated and mechanically ventilated (MV) and rescanned with a standard ventilation protocol (56 bpm, 8 mL/kg and PEEP of 5 cm H2O) and again with a ventilation protocol that approximates the free-breathing parameters (88 bpm, 2.14 mL/kg and PEEP of 2.5 cm H2O). Images were reconstructed representing inspiration and end expiration with 0.15 mm voxel spacing. Image-based measurements of the lung lengths, airway diameters, lung volume, and air content were compared and used to calculate the functional residual capacity (FRC) and tidal volume. Images acquired during MV appeared darker in the airspaces and the airways appeared larger. Image-based measurements showed an increase in lung volume and air content during standard MV, for both respiratory phases, compared with matched MV and free-breathing. Comparisons of the functional metrics showed an increase in FRC for mechanically ventilated rats, but only the standard MV exhibited a significantly higher tidal volume than free-breathing or matched MV Although standard mechanical ventilation protocols may be useful in promoting consistent respiratory patterns, the amount of air in the lungs is higher than in free-breathing animals. Matching the respiratory patterns with the free-breathing case allowed similar lung morphology and physiology measurements while reducing the variability in the measurements.
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Affiliation(s)
- Nancy L Ford
- Department of Oral Biological and Medical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada .,Department of Physics and Astronomy, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Lynda McCaig
- Lawson Health Research Institute, London, Ontario, Canada
| | - Andrew Jeklin
- Department of Oral Biological and Medical Sciences, The University of British Columbia, Vancouver, British Columbia, Canada
| | - James F Lewis
- Lawson Health Research Institute, London, Ontario, Canada.,Departments of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Ruud A W Veldhuizen
- Lawson Health Research Institute, London, Ontario, Canada.,Departments of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - David W Holdsworth
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada.,Medical Biophysics, University of Western Ontario, London, Ontario, Canada.,Medical Imaging, University of Western Ontario, London, Ontario, Canada
| | - Maria Drangova
- Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada.,Medical Biophysics, University of Western Ontario, London, Ontario, Canada.,Medical Imaging, University of Western Ontario, London, Ontario, Canada
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Puett C, Inscoe C, Hartman A, Calliste J, Franceschi DK, Lu J, Zhou O, Lee YZ. An update on carbon nanotube-enabled X-ray sources for biomedical imaging. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2017; 10. [PMID: 28398001 DOI: 10.1002/wnan.1475] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 02/04/2017] [Accepted: 03/11/2017] [Indexed: 11/10/2022]
Abstract
A new imaging technology has emerged that uses carbon nanotubes (CNT) as the electron emitter (cathode) for the X-ray tube. Since the performance of the CNT cathode is controlled by simple voltage manipulation, CNT-enabled X-ray sources are ideal for the repetitive imaging steps needed to capture three-dimensional information. As such, they have allowed the development of a gated micro-computed tomography (CT) scanner for small animal research as well as stationary tomosynthesis, an experimental technology for large field-of-view human imaging. The small animal CT can acquire images at specific points in the respiratory and cardiac cycles. Longitudinal imaging therefore becomes possible and has been applied to many research questions, ranging from tumor response to the noninvasive assessment of cardiac output. Digital tomosynthesis (DT) is a low-dose and low-cost human imaging tool that captures some depth information. Known as three-dimensional mammography, DT is now used clinically for breast imaging. However, the resolution of currently-approved DT is limited by the need to swing the X-ray source through space to collect a series of projection views. An array of fixed and distributed CNT-enabled sources provides the solution and has been used to construct stationary DT devices for breast, lung, and dental imaging. To date, over 100 patients have been imaged on Institutional Review Board-approved study protocols. Early experience is promising, showing an excellent conspicuity of soft-tissue features, while also highlighting technical and post-acquisition processing limitations that are guiding continued research and development. Additionally, CNT-enabled sources are being tested in miniature X-ray tubes that are capable of generating adequate photon energies and tube currents for clinical imaging. Although there are many potential applications for these small field-of-view devices, initial experience has been with an X-ray source that can be inserted into the mouth for dental imaging. Conceived less than 20 years ago, CNT-enabled X-ray sources are now being manufactured on a commercial scale and are powering both research tools and experimental human imaging devices. WIREs Nanomed Nanobiotechnol 2018, 10:e1475. doi: 10.1002/wnan.1475 This article is categorized under: Diagnostic Tools > Diagnostic Nanodevices Diagnostic Tools > In Vivo Nanodiagnostics and Imaging.
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Affiliation(s)
- Connor Puett
- Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, USA
| | - Christina Inscoe
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC, USA.,Department of Applied Physical Sciences, University of North Carolina, Chapel Hill, NC, USA
| | - Allison Hartman
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC, USA
| | - Jabari Calliste
- Department of Applied Physical Sciences, University of North Carolina, Chapel Hill, NC, USA
| | - Dora K Franceschi
- Department of Radiology, University of North Carolina, Chapel Hill, NC, USA
| | - Jianping Lu
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC, USA.,Department of Applied Physical Sciences, University of North Carolina, Chapel Hill, NC, USA
| | - Otto Zhou
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC, USA.,Department of Applied Physical Sciences, University of North Carolina, Chapel Hill, NC, USA
| | - Yueh Z Lee
- Joint Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, USA.,Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC, USA.,Department of Radiology, University of North Carolina, Chapel Hill, NC, USA
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Cleveland ZI, Zhou YM, Akinyi TG, Dunn RS, Davidson CR, Guo J, Woods JC, Hardie WD. Magnetic resonance imaging of disease progression and resolution in a transgenic mouse model of pulmonary fibrosis. Am J Physiol Lung Cell Mol Physiol 2017; 312:L488-L499. [PMID: 28130263 PMCID: PMC5407091 DOI: 10.1152/ajplung.00458.2016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 12/15/2016] [Accepted: 01/19/2017] [Indexed: 01/17/2023] Open
Abstract
Pulmonary fibrosis contributes to morbidity and mortality in a range of diseases, and there are no approved therapies for reversing its progression. To understand the mechanisms underlying pulmonary fibrosis and assess potential therapies, mouse models are central to basic and translational research. Unfortunately, metrics commonly used to assess murine pulmonary fibrosis require animals to be grouped and euthanized, increasing experimental difficulty and cost. We examined the ability of magnetic resonance imaging (MRI) to noninvasively assess lung fibrosis progression and resolution in a doxycycline (Dox) regulatable, transgenic mouse model that overexpresses transforming growth factor-α (TGF-α) under control of a lung-epithelial-specific promoter. During 7 wk of Dox treatment, fibrotic lesions were readily observed as high-signal tissue. Mean weighted signal and percent signal volume were found to be the most robust MRI-derived measures of fibrosis, and these metrics correlated significantly with pleural thickness, histology scores, and hydroxyproline content (R = 0.75-0.89). When applied longitudinally, percent high signal volume increased by 1.5% wk-1 (P < 0.001) and mean weighted signal increased at a rate of 0.0065 wk-1 (P = 0.0062). Following Dox treatment, lesions partially resolved, with percent high signal volume decreasing by -3.2% wk-1 (P = 0.0034) and weighted mean signal decreasing at -0.015 wk-1 (P = 0.0028). Additionally, longitudinal MRI revealed dynamic remodeling in a subset of lesions, a previously unobserved behavior in this model. These results demonstrate MRI can noninvasively assess experimental lung fibrosis progression and resolution and provide unique insights into its pathobiology.
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Affiliation(s)
- Zackary I Cleveland
- Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio;
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
- Department of Biomedical Engineering, University of Cincinnati, Cincinnati, Ohio
- Imaging Research Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Yu M Zhou
- Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
- University of Cincinnati College of Medicine, Cincinnati, Ohio; and
| | - Teckla G Akinyi
- Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
- Department of Biomedical Engineering, University of Cincinnati, Cincinnati, Ohio
| | - R Scott Dunn
- Imaging Research Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Cynthia R Davidson
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Jinbang Guo
- Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
- Department of Physics, Washington University, St. Louis, Missouri
| | - Jason C Woods
- Center for Pulmonary Imaging Research, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
- Imaging Research Center, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
- Department of Physics, Washington University, St. Louis, Missouri
| | - William D Hardie
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
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Frelin-Labalme AM, Beaudouin V. Development of a dynamic phantom and investigation of mobile target imaging and irradiation in preclinical small animal research. Br J Radiol 2016; 90:20160442. [PMID: 27826982 DOI: 10.1259/bjr.20160442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE Progress made in preclinical radiotherapy makes respiratory gating reachable. Nevertheless, technical means are still needed, as well as accurate investigations of the effect of motion on small animal treatment plans. METHODS An animal-scaled dynamic phantom (0.3-11.1-mm motion peak-to-peak amplitude, 30-120 cycles per minute) was developed and characterized. It was used to evaluate respiratory monitoring and high resolution imaging (μPET/CT scans). The width and position variations of a fluorine-18 solution were measured for various motions and gating configurations. The phantom was finally used to measure the impact of motion on dose distribution for vertical irradiation using 2.5- and 5-mm collimations. RESULTS Phantom motions accurately reproduced original waveforms with good rate and amplitude linearity (R2 = 1 and R2 = 0.9995, respectively). µPET/CT acquisitions showed an increase of 92% of the target size caused by a 4.9-mm sine motion and reduced to <12% by gating. Target motion measurements showed consistency better than 18% between modalities. Irradiations showed that motions >0.8 and 1.1 mm (for the 2.5- and 5-mm collimations, respectively) significantly impact dose homogeneity in the target. CONCLUSION The phantom allowed studying motion in small animal imaging and irradiation. It showed the important impact of motions >2 mm and provided accurate data to improve the management of mobile tumour irradiation. The implementation of gated irradiation, associated with motion-compensated imaging, is currently under progress. Advances in knowledge: Small animal irradiation gating is not yet used in preclinical studies. As few solutions are under development, tools and accurate studies are highly needed.
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Affiliation(s)
- Anne-Marie Frelin-Labalme
- 1 Grand Accélérateur National d'Ions Lourds (GANIL), CEA/DRF-CNRS/IN2P3, Boulevard Henri Becquerel, 14076 Caen, France.,2 Advanced Resource Centre for Hadrontherapy in Europe (ARCHADE) Program, Caen, France
| | - Vincent Beaudouin
- 3 CEA, DRF, I2BM, LDM-TEP, GIP Cyceron, Boulevard Henri Becquerel, 14074 Caen, France
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Clark DP, Lee CL, Kirsch DG, Badea CT. Spectrotemporal CT data acquisition and reconstruction at low dose. Med Phys 2016; 42:6317-36. [PMID: 26520724 DOI: 10.1118/1.4931407] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
PURPOSE X-ray computed tomography (CT) is widely used, both clinically and preclinically, for fast, high-resolution anatomic imaging; however, compelling opportunities exist to expand its use in functional imaging applications. For instance, spectral information combined with nanoparticle contrast agents enables quantification of tissue perfusion levels, while temporal information details cardiac and respiratory dynamics. The authors propose and demonstrate a projection acquisition and reconstruction strategy for 5D CT (3D+dual energy+time) which recovers spectral and temporal information without substantially increasing radiation dose or sampling time relative to anatomic imaging protocols. METHODS The authors approach the 5D reconstruction problem within the framework of low-rank and sparse matrix decomposition. Unlike previous work on rank-sparsity constrained CT reconstruction, the authors establish an explicit rank-sparse signal model to describe the spectral and temporal dimensions. The spectral dimension is represented as a well-sampled time and energy averaged image plus regularly undersampled principal components describing the spectral contrast. The temporal dimension is represented as the same time and energy averaged reconstruction plus contiguous, spatially sparse, and irregularly sampled temporal contrast images. Using a nonlinear, image domain filtration approach, the authors refer to as rank-sparse kernel regression, the authors transfer image structure from the well-sampled time and energy averaged reconstruction to the spectral and temporal contrast images. This regularization strategy strictly constrains the reconstruction problem while approximately separating the temporal and spectral dimensions. Separability results in a highly compressed representation for the 5D data in which projections are shared between the temporal and spectral reconstruction subproblems, enabling substantial undersampling. The authors solved the 5D reconstruction problem using the split Bregman method and GPU-based implementations of backprojection, reprojection, and kernel regression. Using a preclinical mouse model, the authors apply the proposed algorithm to study myocardial injury following radiation treatment of breast cancer. RESULTS Quantitative 5D simulations are performed using the MOBY mouse phantom. Twenty data sets (ten cardiac phases, two energies) are reconstructed with 88 μm, isotropic voxels from 450 total projections acquired over a single 360° rotation. In vivo 5D myocardial injury data sets acquired in two mice injected with gold and iodine nanoparticles are also reconstructed with 20 data sets per mouse using the same acquisition parameters (dose: ∼60 mGy). For both the simulations and the in vivo data, the reconstruction quality is sufficient to perform material decomposition into gold and iodine maps to localize the extent of myocardial injury (gold accumulation) and to measure cardiac functional metrics (vascular iodine). Their 5D CT imaging protocol represents a 95% reduction in radiation dose per cardiac phase and energy and a 40-fold decrease in projection sampling time relative to their standard imaging protocol. CONCLUSIONS Their 5D CT data acquisition and reconstruction protocol efficiently exploits the rank-sparse nature of spectral and temporal CT data to provide high-fidelity reconstruction results without increased radiation dose or sampling time.
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Affiliation(s)
- Darin P Clark
- Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina 27710
| | - Chang-Lung Lee
- Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710
| | - David G Kirsch
- Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 and Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710
| | - Cristian T Badea
- Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina 27710
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Assessment of shear stress related parameters in the carotid bifurcation using mouse-specific FSI simulations. J Biomech 2016; 49:2135-2142. [DOI: 10.1016/j.jbiomech.2015.11.048] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 11/07/2015] [Indexed: 01/07/2023]
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Marenzana M, Vande Velde G. Refine, reduce, replace: Imaging of fibrosis and arthritis in animal models. Best Pract Res Clin Rheumatol 2015; 29:715-40. [DOI: 10.1016/j.berh.2016.02.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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30
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Vande Velde G, Poelmans J, De Langhe E, Hillen A, Vanoirbeek J, Himmelreich U, Lories RJ. Longitudinal micro-CT provides biomarkers of lung disease that can be used to assess the effect of therapy in preclinical mouse models, and reveal compensatory changes in lung volume. Dis Model Mech 2015; 9:91-8. [PMID: 26563390 PMCID: PMC4728330 DOI: 10.1242/dmm.020321] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 11/08/2015] [Indexed: 02/02/2023] Open
Abstract
In vivo lung micro-computed tomography (micro-CT) is being increasingly embraced in pulmonary research because it provides longitudinal information on dynamic disease processes in a field in which ex vivo assessment of experimental disease models is still the gold standard. To optimize the quantitative monitoring of progression and therapy of lung diseases, we evaluated longitudinal changes in four different micro-CT-derived biomarkers [aerated lung volume, lung tissue (including lesions) volume, total lung volume and mean lung density], describing normal development, lung infections, inflammation, fibrosis and therapy. Free-breathing mice underwent micro-CT before and repeatedly after induction of lung disease (bleomycin-induced fibrosis, invasive pulmonary aspergillosis, pulmonary cryptococcosis) and therapy (imatinib). The four lung biomarkers were quantified. After the last time point, we performed pulmonary function tests and isolated the lungs for histology. None of the biomarkers remained stable during longitudinal follow-up of adult healthy mouse lungs, implying that biomarkers should be compared with age-matched controls upon intervention. Early inflammation and progressive fibrosis led to a substantial increase in total lung volume, which affects the interpretation of aerated lung volume, tissue volume and mean lung density measures. Upon treatment of fibrotic lung disease, the improvement in aerated lung volume and function was not accompanied by a normalization of the increased total lung volume. Significantly enlarged lungs were also present in models of rapidly and slowly progressing lung infections. The data suggest that total lung volume changes could partly reflect a compensatory mechanism that occurs during disease progression in mice. Our findings underscore the importance of quantifying total lung volume in addition to aerated lung or lesion volumes to accurately document growth and potential compensatory mechanisms in mouse models of lung disease, in order to fully describe and understand dynamic processes during lung disease onset, progression and therapy. This is highly relevant for the translation of therapy evaluation results from preclinical studies to human patients.
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Affiliation(s)
- Greetje Vande Velde
- Biomedical MRI/MoSAIC, Department of Imaging and Pathology, KU Leuven, B-3000 Leuven, Flanders, Belgium
| | - Jennifer Poelmans
- Biomedical MRI/MoSAIC, Department of Imaging and Pathology, KU Leuven, B-3000 Leuven, Flanders, Belgium
| | - Ellen De Langhe
- Laboratory of Tissue Homeostasis and Disease, Skeletal Biology and Engineering Research Center, Department of Development and Regeneration, KU Leuven, B-3000 Leuven, Flanders, Belgium Division of Rheumatology, University Hospitals Leuven, B-3000 Leuven, Flanders, Belgium
| | - Amy Hillen
- Biomedical MRI/MoSAIC, Department of Imaging and Pathology, KU Leuven, B-3000 Leuven, Flanders, Belgium
| | - Jeroen Vanoirbeek
- Centre for Environment and Health, Department of Public Health and Primary Care, KU Leuven, B-3000 Leuven, Flanders, Belgium
| | - Uwe Himmelreich
- Biomedical MRI/MoSAIC, Department of Imaging and Pathology, KU Leuven, B-3000 Leuven, Flanders, Belgium
| | - Rik J Lories
- Laboratory of Tissue Homeostasis and Disease, Skeletal Biology and Engineering Research Center, Department of Development and Regeneration, KU Leuven, B-3000 Leuven, Flanders, Belgium Division of Rheumatology, University Hospitals Leuven, B-3000 Leuven, Flanders, Belgium
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Ashton JR, West JL, Badea CT. In vivo small animal micro-CT using nanoparticle contrast agents. Front Pharmacol 2015; 6:256. [PMID: 26581654 PMCID: PMC4631946 DOI: 10.3389/fphar.2015.00256] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 10/19/2015] [Indexed: 12/12/2022] Open
Abstract
Computed tomography (CT) is one of the most valuable modalities for in vivo imaging because it is fast, high-resolution, cost-effective, and non-invasive. Moreover, CT is heavily used not only in the clinic (for both diagnostics and treatment planning) but also in preclinical research as micro-CT. Although CT is inherently effective for lung and bone imaging, soft tissue imaging requires the use of contrast agents. For small animal micro-CT, nanoparticle contrast agents are used in order to avoid rapid renal clearance. A variety of nanoparticles have been used for micro-CT imaging, but the majority of research has focused on the use of iodine-containing nanoparticles and gold nanoparticles. Both nanoparticle types can act as highly effective blood pool contrast agents or can be targeted using a wide variety of targeting mechanisms. CT imaging can be further enhanced by adding spectral capabilities to separate multiple co-injected nanoparticles in vivo. Spectral CT, using both energy-integrating and energy-resolving detectors, has been used with multiple contrast agents to enable functional and molecular imaging. This review focuses on new developments for in vivo small animal micro-CT using novel nanoparticle probes applied in preclinical research.
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Affiliation(s)
- Jeffrey R Ashton
- Department of Biomedical Engineering, Duke University, Durham NC, USA ; Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham NC, USA
| | - Jennifer L West
- Department of Biomedical Engineering, Duke University, Durham NC, USA
| | - Cristian T Badea
- Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham NC, USA
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Ritman EL. In vivo X-Ray Phase Imaging. EBioMedicine 2015; 2:1304-5. [PMID: 26629520 PMCID: PMC4634695 DOI: 10.1016/j.ebiom.2015.09.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 09/04/2015] [Indexed: 12/02/2022] Open
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Boerckel JD, Mason DE, McDermott AM, Alsberg E. Microcomputed tomography: approaches and applications in bioengineering. Stem Cell Res Ther 2014; 5:144. [PMID: 25689288 PMCID: PMC4290379 DOI: 10.1186/scrt534] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Microcomputed tomography (microCT) has become a standard and essential tool for quantifying structure-function relationships, disease progression, and regeneration in preclinical models and has facilitated numerous scientific and bioengineering advancements over the past 30 years. In this article, we recount the early events that led to the initial development of microCT and review microCT approaches for quantitative evaluation of bone, cartilage, and cardiovascular structures, with applications in fundamental structure-function analysis, disease, tissue engineering, and numerical modeling. Finally, we address several next-generation approaches under active investigation to improve spatial resolution, acquisition time, tissue contrast, radiation dose, and functional and molecular information.
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Maier J, Sawall S, Kachelrieß M. Assessment of dedicated low-dose cardiac micro-CT reconstruction algorithms using the left ventricular volume of small rodents as a performance measure. Med Phys 2014; 41:051908. [PMID: 24784387 DOI: 10.1118/1.4870983] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Phase-correlated microcomputed tomography (micro-CT) imaging plays an important role in the assessment of mouse models of cardiovascular diseases and the determination of functional parameters as the left ventricular volume. As the current gold standard, the phase-correlated Feldkamp reconstruction (PCF), shows poor performance in case of low dose scans, more sophisticated reconstruction algorithms have been proposed to enable low-dose imaging. In this study, the authors focus on the McKinnon-Bates (MKB) algorithm, the low dose phase-correlated (LDPC) reconstruction, and the high-dimensional total variation minimization reconstruction (HDTV) and investigate their potential to accurately determine the left ventricular volume at different dose levels from 50 to 500 mGy. The results were verified in phantom studies of a five-dimensional (5D) mathematical mouse phantom. METHODS Micro-CT data of eight mice, each administered with an x-ray dose of 500 mGy, were acquired, retrospectively gated for cardiac and respiratory motion and reconstructed using PCF, MKB, LDPC, and HDTV. Dose levels down to 50 mGy were simulated by using only a fraction of the projections. Contrast-to-noise ratio (CNR) was evaluated as a measure of image quality. Left ventricular volume was determined using different segmentation algorithms (Otsu, level sets, region growing). Forward projections of the 5D mouse phantom were performed to simulate a micro-CT scan. The simulated data were processed the same way as the real mouse data sets. RESULTS Compared to the conventional PCF reconstruction, the MKB, LDPC, and HDTV algorithm yield images of increased quality in terms of CNR. While the MKB reconstruction only provides small improvements, a significant increase of the CNR is observed in LDPC and HDTV reconstructions. The phantom studies demonstrate that left ventricular volumes can be determined accurately at 500 mGy. For lower dose levels which were simulated for real mouse data sets, the HDTV algorithm shows the best performance. At 50 mGy, the deviation from the reference obtained at 500 mGy were less than 4%. Also the LDPC algorithm provides reasonable results with deviation less than 10% at 50 mGy while PCF and MKB reconstruction show larger deviations even at higher dose levels. CONCLUSIONS LDPC and HDTV increase CNR and allow for quantitative evaluations even at dose levels as low as 50 mGy. The left ventricular volumes exemplarily illustrate that cardiac parameters can be accurately estimated at lowest dose levels if sophisticated algorithms are used. This allows to reduce dose by a factor of 10 compared to today's gold standard and opens new options for longitudinal studies of the heart.
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Affiliation(s)
- Joscha Maier
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
| | - Stefan Sawall
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany and Institute of Medical Physics, University of Erlangen-Nürnberg, 91052 Erlangen, Germany
| | - Marc Kachelrieß
- Medical Physics in Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany and Institute of Medical Physics, University of Erlangen-Nürnberg, 91052 Erlangen, Germany
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Abstract
PURPOSE The objective of this study was to compare a new generation of four-dimensional micro-single photon emission computed tomography (microSPECT) with microCT for the quantitative in vivo assessment of murine cardiac function. PROCEDURES Four-dimensional isotropic cardiac images were acquired from anesthetized normal C57BL/6 mice with either microSPECT (n = 6) or microCT (n = 6). One additional mouse with myocardial infarction (MI) was scanned with both modalities. Prior to imaging, mice were injected with either technetium tetrofosmin for microSPECT or a liposomal blood pool contrast agent for microCT. Segmentation of the left ventricle (LV) was performed using Vitrea (Vital Images) software, to derive global and regional function. RESULTS Measures of global LV function between microSPECT and microCT groups were comparable (e.g., ejection fraction = 71 ± 6 % microSPECT and 68 ± 4 % microCT). Regional functional indices (wall motion, wall thickening, regional ejection fraction) were also similar for the two modalities. In the mouse with MI, microSPECT identified a large perfusion defect that was not evident with microCT. CONCLUSIONS Despite lower spatial resolution, microSPECT was comparable to microCT in the quantitative evaluation of cardiac function. MicroSPECT offers an advantage over microCT in the ability to evaluate simultaneously myocardial radiotracer distribution and function, simultaneously. MicroSPECT should be considered as an alternative to microCT and magnetic resonance for preclinical cardiac imaging in the mouse.
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Clark DP, Badea CT. Micro-CT of rodents: state-of-the-art and future perspectives. Phys Med 2014; 30:619-34. [PMID: 24974176 PMCID: PMC4138257 DOI: 10.1016/j.ejmp.2014.05.011] [Citation(s) in RCA: 141] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 05/15/2014] [Accepted: 05/28/2014] [Indexed: 02/06/2023] Open
Abstract
Micron-scale computed tomography (micro-CT) is an essential tool for phenotyping and for elucidating diseases and their therapies. This work is focused on preclinical micro-CT imaging, reviewing relevant principles, technologies, and applications. Commonly, micro-CT provides high-resolution anatomic information, either on its own or in conjunction with lower-resolution functional imaging modalities such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT). More recently, however, advanced applications of micro-CT produce functional information by translating clinical applications to model systems (e.g., measuring cardiac functional metrics) and by pioneering new ones (e.g. measuring tumor vascular permeability with nanoparticle contrast agents). The primary limitations of micro-CT imaging are the associated radiation dose and relatively poor soft tissue contrast. We review several image reconstruction strategies based on iterative, statistical, and gradient sparsity regularization, demonstrating that high image quality is achievable with low radiation dose given ever more powerful computational resources. We also review two contrast mechanisms under intense development. The first is spectral contrast for quantitative material discrimination in combination with passive or actively targeted nanoparticle contrast agents. The second is phase contrast which measures refraction in biological tissues for improved contrast and potentially reduced radiation dose relative to standard absorption imaging. These technological advancements promise to develop micro-CT into a commonplace, functional and even molecular imaging modality.
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Affiliation(s)
- D P Clark
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Box 3302, Durham, NC 27710, USA
| | - C T Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Box 3302, Durham, NC 27710, USA.
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Ashton JR, Clark DP, Moding EJ, Ghaghada K, Kirsch DG, West JL, Badea CT. Dual-energy micro-CT functional imaging of primary lung cancer in mice using gold and iodine nanoparticle contrast agents: a validation study. PLoS One 2014; 9:e88129. [PMID: 24520351 PMCID: PMC3919743 DOI: 10.1371/journal.pone.0088129] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Accepted: 01/06/2014] [Indexed: 11/19/2022] Open
Abstract
Purpose To provide additional functional information for tumor characterization, we investigated the use of dual-energy computed tomography for imaging murine lung tumors. Tumor blood volume and vascular permeability were quantified using gold and iodine nanoparticles. This approach was compared with a single contrast agent/single-energy CT method. Ex vivo validation studies were performed to demonstrate the accuracy of in vivo contrast agent quantification by CT. Methods Primary lung tumors were generated in LSL-KrasG12D; p53FL/FL mice. Gold nanoparticles were injected, followed by iodine nanoparticles two days later. The gold accumulated in tumors, while the iodine provided intravascular contrast. Three dual-energy CT scans were performed–two for the single contrast agent method and one for the dual contrast agent method. Gold and iodine concentrations in each scan were calculated using a dual-energy decomposition. For each method, the tumor fractional blood volume was calculated based on iodine concentration, and tumor vascular permeability was estimated based on accumulated gold concentration. For validation, the CT-derived measurements were compared with histology and inductively-coupled plasma optical emission spectroscopy measurements of gold concentrations in tissues. Results Dual-energy CT enabled in vivo separation of gold and iodine contrast agents and showed uptake of gold nanoparticles in the spleen, liver, and tumors. The tumor fractional blood volume measurements determined from the two imaging methods were in agreement, and a high correlation (R2 = 0.81) was found between measured fractional blood volume and histology-derived microvascular density. Vascular permeability measurements obtained from the two imaging methods agreed well with ex vivo measurements. Conclusions Dual-energy CT using two types of nanoparticles is equivalent to the single nanoparticle method, but allows for measurement of fractional blood volume and permeability with a single scan. As confirmed by ex vivo methods, CT-derived nanoparticle concentrations are accurate. This method could play an important role in lung tumor characterization by CT.
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Affiliation(s)
- Jeffrey R. Ashton
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
| | - Darin P. Clark
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
| | - Everett J. Moding
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Ketan Ghaghada
- The Edward B. Singleton Department of Pediatric Radiology, Texas Children’s Hospital, Houston, Texas, United States of America
| | - David G. Kirsch
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Jennifer L. West
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, United States of America
| | - Cristian T. Badea
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail:
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Long DS, Zhu H, Friedman MH. Microscope-based near-infrared stereo-imaging system for quantifying the motion of the murine epicardial coronary arteries in vivo. JOURNAL OF BIOMEDICAL OPTICS 2013; 18:096013. [PMID: 24057233 PMCID: PMC3779146 DOI: 10.1117/1.jbo.18.9.096013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 08/02/2013] [Accepted: 08/20/2013] [Indexed: 06/02/2023]
Abstract
Atherosclerosis is a leading cause of mortality in industrialized countries. In addition to "traditional" systemic risk factors for atherosclerosis, the geometry and motion of coronary arteries may contribute to individual susceptibility to the development and progression of disease in these vessels. To be able to test this, we have developed a high-speed (∼40 frames per second) microscope-based stereo-imaging system to quantify the motion of epicardial coronary arteries of mice. Using near-infrared nontargeted quantum dots as an imaging contrast agent, we synchronously acquired paired images of a surgically exposed murine heart, from which the three-dimensional geometry of the coronary arteries was reconstructed. The reconstructed geometry was tracked frame by frame through the cardiac cycle to quantify the in vivo motion of the vessel, from which displacements, curvature, and torsion parameters were derived. Illustrative results for a C57BL/6J mouse are presented.
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Affiliation(s)
- David S. Long
- Duke University, Department of Biomedical Engineering, Durham, North Carolina 27708
- University of Auckland, Auckland Bioengineering Institute, 70 Symonds Street, Auckland 1142, New Zealand
| | - Hui Zhu
- Duke University, Department of Biomedical Engineering, Durham, North Carolina 27708
| | - Morton H. Friedman
- Duke University, Department of Biomedical Engineering, Durham, North Carolina 27708
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Armitage SEJ, Pollmann SI, Detombe SA, Drangova M. Least-error projection sorting to optimize retrospectively gated cardiac micro-CT of free-breathing mice. Med Phys 2013; 39:1452-61. [PMID: 22380378 DOI: 10.1118/1.3681949] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To develop and characterize a technique for optimizing image quality by eliminating streaking artifacts in retrospectively gated microcomputed tomography (micro-CT) images of mice caused by insufficient and irregular angular sampling. METHODS A least-error sorting technique was developed to minimize streak artifacts in retrospectively gated cardiac micro-CT images. To ensure complete filling of projection space, for each angular position, the projection acquired closest to the desired cardiac phase is used to reconstruct a volumetric image. An acrylic slanted-edge phantom undergoing cyclic motion was used to characterize the system's resolution. The phantom was scanned using a volumetric micro-CT scanner equipped with a flat-panel detector mounted on a slip-ring gantry. Projection images of the moving phantom were collected over a period of 60 s using a variety of acquisition protocols with the rotation period of the gantry ranging from 1 to 5 s. The modulation transfer function (MTF) of the reconstructed images was measured for many combinations of acquisition and reconstruction parameters. The use of the least-error technique was also demonstrated in vivo. RESULTS The motion blurring introduced into the images at physiologically significant velocities of 6 cm∕s agreed well with predicted values; limiting resolution (frequency at 10% MTF) degraded from 2.5 to 1.0 mm(-1) for a velocity of 6 cm∕s and 5 s∕rotation gantry speed. Faster gantry rotation speeds led to improved temporal resolution but the scanner's data storage and transfer rates and field of view limitations made scanning at gantry speeds faster than 2 s∕rotation impractical. CONCLUSIONS The least-error technique effectively eliminates streaking artifact caused by missing views and allows for optimization of image quality in retrospectively gated micro-CT.
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Pandit P, Johnston SM, Qi Y, Story J, Nelson R, Johnson GA. The utility of micro-CT and MRI in the assessment of longitudinal growth of liver metastases in a preclinical model of colon carcinoma. Acad Radiol 2013; 20:430-9. [PMID: 23498983 DOI: 10.1016/j.acra.2012.09.030] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 09/17/2012] [Accepted: 09/24/2012] [Indexed: 12/30/2022]
Abstract
RATIONALE AND OBJECTIVES Liver is a common site for distal metastases in colon and rectal cancer. Numerous clinical studies have analyzed the relative merits of different imaging modalities for detection of liver metastases. Several exciting new therapies are being investigated in preclinical models. But, technical challenges in preclinical imaging make it difficult to translate conclusions from clinical studies to the preclinical environment. This study addresses the technical challenges of preclinical magnetic resonance imaging (MRI) and micro-computed tomography (CT) to enable comparison of state-of-the-art methods for following metastatic liver disease. MATERIALS AND METHODS We optimized two promising preclinical protocols to enable a parallel longitudinal study tracking metastatic human colon carcinoma growth in a mouse model: T2-weighted MRI using two-shot PROPELLER (Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction) and contrast-enhanced micro-CT using a liposomal contrast agent. Both methods were tailored for high throughput with attention to animal support and anesthesia to limit biological stress. RESULTS AND CONCLUSIONS Each modality has its strengths. Micro-CT permitted more rapid acquisition (<10 minutes) with the highest spatial resolution (88-micron isotropic resolution). But detection of metastatic lesions requires the use of a blood pool contrast agent, which could introduce a confound in the evaluation of new therapies. MRI was slower (30 minutes) and had lower anisotropic spatial resolution. But MRI eliminates the need for a contrast agent and the contrast-to-noise between tumor and normal parenchyma was higher, making earlier detection of small lesions possible. Both methods supported a relatively high-throughput, longitudinal study of the development of metastatic lesions.
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Bhavane R, Badea C, Ghaghada KB, Clark D, Vela D, Moturu A, Annapragada A, Johnson GA, Willerson JT, Annapragada A. Dual-energy computed tomography imaging of atherosclerotic plaques in a mouse model using a liposomal-iodine nanoparticle contrast agent. Circ Cardiovasc Imaging 2013; 6:285-94. [PMID: 23349231 DOI: 10.1161/circimaging.112.000119] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The accumulation of macrophages in inflamed atherosclerotic plaques has long been recognized. In an attempt to develop an imaging agent for detection of vulnerable plaques, we evaluated the feasibility of a liposomal-iodine nanoparticle contrast agent for computed tomography imaging of macrophage-rich atherosclerotic plaques in a mouse model. METHODS AND RESULTS Liposomal-iodine formulations varying in particle size and polyethylene glycol coating were fabricated and shown to stably encapsulate the iodine compound. In vitro uptake studies using optical and computed tomography imaging in the RAW 264.7 macrophage cell line identified the formulation that promoted maximal uptake. Dual-energy computed tomography imaging using this formulation in apolipoprotein E-deficient (ApoE(-/-)) mice (n=8) and control C57BL/6 mice (n=6) followed by spectral decomposition of the dual-energy images enabled imaging of the liposomes localized in the plaque. Imaging cytometry confirmed the presence of liposomes in the plaque and their colocalization with a small fraction (≈2%) of the macrophages in the plaque. CONCLUSIONS The results demonstrate the feasibility of imaging macrophage-rich atherosclerotic plaques using a liposomal-iodine nanoparticle contrast agent and dual-energy computed tomography.
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Affiliation(s)
- Rohan Bhavane
- Singleton Department of Pediatric Radiology, Texas Children's Hospital, Houston, TX 77030, USA
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A LabVIEW Platform for Preclinical Imaging Using Digital Subtraction Angiography and Micro-CT. J Med Eng 2013; 2013:581617. [PMID: 27006920 PMCID: PMC4782637 DOI: 10.1155/2013/581617] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2012] [Accepted: 01/21/2013] [Indexed: 12/02/2022] Open
Abstract
CT and digital subtraction angiography (DSA) are ubiquitous in the clinic. Their preclinical equivalents are valuable imaging methods for studying disease models and treatment. We have developed a dual source/detector X-ray imaging system that we have used for both micro-CT and DSA studies in rodents. The control of such a complex imaging system requires substantial software development for which we use the graphical language LabVIEW (National Instruments, Austin, TX, USA). This paper focuses on a LabVIEW platform that we have developed to enable anatomical and functional imaging with micro-CT and DSA. Our LabVIEW applications integrate and control all the elements of our system including a dual source/detector X-ray system, a mechanical ventilator, a physiological monitor, and a power microinjector for the vascular delivery of X-ray contrast agents. Various applications allow cardiac- and respiratory-gated acquisitions for both DSA and micro-CT studies. Our results illustrate the application of DSA for cardiopulmonary studies and vascular imaging of the liver and coronary arteries. We also show how DSA can be used for functional imaging of the kidney. Finally, the power of 4D micro-CT imaging using both prospective and retrospective gating is shown for cardiac imaging.
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Airway distension during lung inflation in healthy and allergic-sensitised mice in vivo. Respir Physiol Neurobiol 2012; 185:639-46. [PMID: 23253555 DOI: 10.1016/j.resp.2012.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 11/14/2012] [Accepted: 12/06/2012] [Indexed: 11/22/2022]
Abstract
We evaluated the airway distention during lung inflation of varying size in healthy and allergic-sensitised mice in vivo. Computed tomography (CT) images of healthy and ovalbumin-treated mice were acquired using a synchrotron in vivo CT system when lung pressures was 0 and 20 cmH(2)O, and the morphometric distension (diameter, length, and volume) and the compliance of airway segments (to as small as ~150 μm internal diameter) were calculated. With respect to airway size, in healthy mice, the changes in airway diameter and compliance were larger in the small-airway group. In contrast, in allergic-sensitised mice, there were no significant differences in the changes in airway distension or compliance. Airway wall thickness in allergic-sensitised mice increased significantly in all airway groups, but the change was much larger in the small than in the large-airway group. Compared with healthy airways, the changes in diameter and airway compliance of the allergic-sensitised mice were significantly smaller in the small-airway group.
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Clark D, Badea A, Liu Y, Johnson GA, Badea CT. Registration-based segmentation of murine 4D cardiac micro-CT data using symmetric normalization. Phys Med Biol 2012; 57:6125-45. [PMID: 22971564 DOI: 10.1088/0031-9155/57/19/6125] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Micro-CT can play an important role in preclinical studies of cardiovascular disease because of its high spatial and temporal resolution. Quantitative analysis of 4D cardiac images requires segmentation of the cardiac chambers at each time point, an extremely time consuming process if done manually. To improve throughput this study proposes a pipeline for registration-based segmentation and functional analysis of 4D cardiac micro-CT data in the mouse. Following optimization and validation using simulations, the pipeline was applied to in vivo cardiac micro-CT data corresponding to ten cardiac phases acquired in C57BL/6 mice (n = 5). After edge-preserving smoothing with a novel adaptation of 4D bilateral filtration, one phase within each cardiac sequence was manually segmented. Deformable registration was used to propagate these labels to all other cardiac phases for segmentation. The volumes of each cardiac chamber were calculated and used to derive stroke volume, ejection fraction, cardiac output, and cardiac index. Dice coefficients and volume accuracies were used to compare manual segmentations of two additional phases with their corresponding propagated labels. Both measures were, on average, >0.90 for the left ventricle and >0.80 for the myocardium, the right ventricle, and the right atrium, consistent with trends in inter- and intra-segmenter variability. Segmentation of the left atrium was less reliable. On average, the functional metrics of interest were underestimated by 6.76% or more due to systematic label propagation errors around atrioventricular valves; however, execution of the pipeline was 80% faster than performing analogous manual segmentation of each phase.
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Affiliation(s)
- Darin Clark
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, NC 27710, USA
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Constantinesco A, Choquet P, Goetz C, Monassier L. PET, SPECT, CT, and MRI in Mouse Cardiac Phenotyping: An Overview. ACTA ACUST UNITED AC 2012; 2:129-44. [DOI: 10.1002/9780470942390.mo110225] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- André Constantinesco
- Laboratoire d'Imagerie Préclinique, Service de Biophysique et Médecine Nucléaire, Hôpitaux Universitaires de Strasbourg; Strasbourg France
| | - Philippe Choquet
- Laboratoire d'Imagerie Préclinique, Service de Biophysique et Médecine Nucléaire, Hôpitaux Universitaires de Strasbourg; Strasbourg France
| | - Christian Goetz
- Laboratoire d'Imagerie Préclinique, Service de Biophysique et Médecine Nucléaire, Hôpitaux Universitaires de Strasbourg; Strasbourg France
| | - Laurent Monassier
- Laboratoire de Neurobiologie et Pharmacologie Cardiovasculaire, Université de Strasbourg; Strasbourg France
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Guo X, Johnston SM, Qi Y, Johnson GA, Badea CT. 4D micro-CT using fast prospective gating. Phys Med Biol 2012; 57:257-71. [PMID: 22156062 DOI: 10.1088/0031-9155/57/1/257] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Micro-CT is currently used in preclinical studies to provide anatomical information. But, there is also significant interest in using this technology to obtain functional information. We report here a new sampling strategy for 4D micro-CT for functional cardiac and pulmonary imaging. Rapid scanning of free-breathing mice is achieved with fast prospective gating (FPG) implemented on a field programmable gate array. The method entails on-the-fly computation of delays from the R peaks of the ECG signals or the peaks of the respiratory signals for the triggering pulses. Projection images are acquired for all cardiac or respiratory phases at each angle before rotating to the next angle. FPG can deliver the faster scan time of retrospective gating (RG) with the regular angular distribution of conventional prospective gating for cardiac or respiratory gating. Simultaneous cardio-respiratory gating is also possible with FPG in a hybrid retrospective/prospective approach. We have performed phantom experiments to validate the new sampling protocol and compared the results from FPG and RG in cardiac imaging of a mouse. Additionally, we have evaluated the utility of incorporating respiratory information in 4D cardiac micro-CT studies with FPG. A dual-source micro-CT system was used for image acquisition with pulsed x-ray exposures (80 kVp, 100 mA, 10 ms). The cardiac micro-CT protocol involves the use of a liposomal blood pool contrast agent containing 123 mg I ml(-1) delivered via a tail vein catheter in a dose of 0.01 ml g(-1) body weight. The phantom experiment demonstrates that FPG can distinguish the successive phases of phantom motion with minimal motion blur, and the animal study demonstrates that respiratory FPG can distinguish inspiration and expiration. 4D cardiac micro-CT imaging with FPG provides image quality superior to RG at an isotropic voxel size of 88 μm and 10 ms temporal resolution. The acquisition time for either sampling approach is less than 5 min. The radiation dose associated with the proposed method is in the range of a typical micro-CT dose (256 mGy for the cardiac study). Ignoring respiration does not significantly affect anatomic information in cardiac studies. FPG can deliver short scan times with low-dose 4D micro-CT imaging without sacrificing image quality. FPG can be applied in high-throughput longitudinal studies in a wide range of applications, including drug safety and cardiopulmonary phenotyping.
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Affiliation(s)
- Xiaolian Guo
- Biomedical Engineering, School of Medicine, Tsinghua University, Beijing, People's Republic of China
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Badea CT, Athreya KK, Espinosa G, Clark D, Ghafoori AP, Li Y, Kirsch DG, Johnson GA, Annapragada A, Ghaghada KB. Computed tomography imaging of primary lung cancer in mice using a liposomal-iodinated contrast agent. PLoS One 2012; 7:e34496. [PMID: 22485175 PMCID: PMC3317632 DOI: 10.1371/journal.pone.0034496] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Accepted: 03/01/2012] [Indexed: 12/21/2022] Open
Abstract
Purpose To investigate the utility of a liposomal-iodinated nanoparticle contrast agent and computed tomography (CT) imaging for characterization of primary nodules in genetically engineered mouse models of non-small cell lung cancer. Methods Primary lung cancers with mutations in K-ras alone (KrasLA1) or in combination with p53 (LSL-KrasG12D;p53FL/FL) were generated. A liposomal-iodine contrast agent containing 120 mg Iodine/mL was administered systemically at a dose of 16 µl/gm body weight. Longitudinal micro-CT imaging with cardio-respiratory gating was performed pre-contrast and at 0 hr, day 3, and day 7 post-contrast administration. CT-derived nodule sizes were used to assess tumor growth. Signal attenuation was measured in individual nodules to study dynamic enhancement of lung nodules. Results A good correlation was seen between volume and diameter-based assessment of nodules (R2>0.8) for both lung cancer models. The LSL-KrasG12D;p53FL/FL model showed rapid growth as demonstrated by systemically higher volume changes compared to the lung nodules in KrasLA1 mice (p<0.05). Early phase imaging using the nanoparticle contrast agent enabled visualization of nodule blood supply. Delayed-phase imaging demonstrated significant differential signal enhancement in the lung nodules of LSL-KrasG12D;p53FL/FL mice compared to nodules in KrasLA1 mice (p<0.05) indicating higher uptake and accumulation of the nanoparticle contrast agent in rapidly growing nodules. Conclusions The nanoparticle iodinated contrast agent enabled visualization of blood supply to the nodules during the early-phase imaging. Delayed-phase imaging enabled characterization of slow growing and rapidly growing nodules based on signal enhancement. The use of this agent could facilitate early detection and diagnosis of pulmonary lesions as well as have implications on treatment response and monitoring.
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Affiliation(s)
- Cristian T. Badea
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail: (CTB); (KBG)
| | - Khannan K. Athreya
- University of Texas Medical School at Houston, The University of Texas Health Sciences Center at Houston, Houston, Texas, United States of America
| | - Gabriela Espinosa
- The Edward B. Singleton Department of Pediatric Radiology, Texas Children's Hospital, Houston, Texas, United States of America
- School of Biomedical Informatics, The University of Texas Health Sciences Center at Houston, Houston, Texas, United States of America
| | - Darin Clark
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina, United States of America
| | - A. Paiman Ghafoori
- Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Yifan Li
- Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - David G. Kirsch
- Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - G. Allan Johnson
- Center for In Vivo Microscopy, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Ananth Annapragada
- The Edward B. Singleton Department of Pediatric Radiology, Texas Children's Hospital, Houston, Texas, United States of America
| | - Ketan B. Ghaghada
- The Edward B. Singleton Department of Pediatric Radiology, Texas Children's Hospital, Houston, Texas, United States of America
- * E-mail: (CTB); (KBG)
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Park CW, Rhee YS, Vogt FG, Hayes D, Zwischenberger JB, DeLuca PP, Mansour HM. Advances in microscopy and complementary imaging techniques to assess the fate of drugs ex vivo in respiratory drug delivery: an invited paper. Adv Drug Deliv Rev 2012; 64:344-56. [PMID: 21920394 DOI: 10.1016/j.addr.2011.08.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Revised: 08/24/2011] [Accepted: 08/30/2011] [Indexed: 12/17/2022]
Abstract
The technical advances in microscopy imaging techniques have been applied to assess the fate of drugs for researching respiratory drug delivery in ex vivo and in vivo experiments. Recent developments in optical imaging (confocal microscopy, multi-photon microscopy, fluorescence imaging (FLI) and bioluminescence imaging (BLI)), and in non-optical imaging (magnetic resonance imaging (MRI), computing tomography (CT), positron-emission tomography (PET) and single-photon-emission computed tomography (SPECT)) are presented with their derivative medical devices. Novel microscopy have been utilized to address many biological questions in basic research and are becoming powerful clinical tools for non-invasive objective diagnosis, guided treatment, and monitoring therapies. The goal of this paper is to present recent advances in microscopy imaging techniques and to discuss their novel applications in respiratory drug delivery imaging.
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Badea CT, Guo X, Clark D, Johnston SM, Marshall CD, Piantadosi CA. Dual-energy micro-CT of the rodent lung. Am J Physiol Lung Cell Mol Physiol 2012; 302:L1088-97. [PMID: 22427526 DOI: 10.1152/ajplung.00359.2011] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this work is to investigate the use of dual-energy micro-computed tomography (CT) for the estimation of vascular, tissue, and air fractions in rodent lungs using a postreconstruction three material decomposition method. Using simulations, we have estimated the accuracy limits of the decomposition for realistic micro-CT noise levels. Next, we performed experiments involving ex vivo lung imaging in which intact rat lungs were carefully removed from the thorax, injected with an iodine-based contrast agent, and then inflated with different volumes of air (n = 2). Finally, we performed in vivo imaging studies in C57BL/6 mice (n = 5) using fast prospective respiratory gating in end inspiration and end expiration for three different levels of positive end expiratory pressure (PEEP). Before imaging, mice were injected with a liposomal blood pool contrast agent. The three-dimensional air, tissue, and blood fraction maps were computed and analyzed. The results indicate that separation and volume estimation of the three material components of the lungs are possible. The mean accuracy values for air, blood, and tissue were 93, 93, and 90%, respectively. The absolute accuracy in determining all fraction materials was 91.6%. The coefficient of variation was small (2.5%) indicating good repeatability. The minimum difference that we could detect in material fractions was 15%. As expected, an increase in PEEP levels for the living mouse resulted in statistically significant increases in air fractions at end expiration but no significant changes at end inspiration. Our method has applicability in preclinical pulmonary studies where changes in lung structure and gas volume as a result of lung injury, environmental exposures, or drug bioactivity would have important physiological implications.
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Affiliation(s)
- C T Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
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Clark D, Johnson GA, Badea CT. Denoising of 4D Cardiac Micro-CT Data Using Median-Centric Bilateral Filtration. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2012; 8314. [PMID: 24386540 DOI: 10.1117/12.911478] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Bilateral filtration has proven an effective tool for denoising CT data. The classic filter utilizes Gaussian domain and range weighting functions in 2D. More recently, other distributions have yielded more accurate results in specific applications, and the bilateral filtration framework has been extended to higher dimensions. In this study, brute-force optimization is employed to evaluate the use of several alternative distributions for both domain and range weighting: Andrew's Sine Wave, El Fallah Ford, Gaussian, Flat, Lorentzian, Huber's Minimax, Tukey's Bi-weight, and Cosine. Two variations on the classic bilateral filter which use median filtration to reduce bias in range weights are also investigated: median-centric and hybrid bilateral filtration. Using the 4D MOBY mouse phantom reconstructed with noise (stdev. ~ 65 HU), hybrid bilateral filtration, a combination of the classic and median-centric filters, with Flat domain and range weighting is shown to provide optimal denoising results (PSNRs: 31.69, classic; 31.58 median-centric; 32.25, hybrid). To validate these phantom studies, the optimal filters are also applied to in vivo, 4D cardiac micro-CT data acquired in the mouse. In a constant region of the left ventricle, hybrid bilateral filtration with Flat domain and range weighting is shown to provide optimal smoothing (stdev: original, 72.2 HU; classic, 20.3 HU; median-centric, 24.1 HU; hybrid, 15.9 HU). While the optimal results were obtained using 4D filtration, the 3D hybrid filter is ultimately recommended for denoising 4D cardiac micro-CT data because it is more computationally tractable and less prone to artifacts (MOBY PSNR: 32.05; left ventricle stdev: 20.5 HU).
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Affiliation(s)
- D Clark
- Center for In Vivo Microscopy, Dept. of Radiology, Duke Univ. Med. Center, Durham, NC 27710
| | - G A Johnson
- Center for In Vivo Microscopy, Dept. of Radiology, Duke Univ. Med. Center, Durham, NC 27710
| | - C T Badea
- Center for In Vivo Microscopy, Dept. of Radiology, Duke Univ. Med. Center, Durham, NC 27710
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