1
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Qiu X, Liu Y, Lv F. Application Value of a Novel Micro-Coil in High-Resolution Imaging of Experimental Mice Based on 3.0 T Clinical MR. Tomography 2024; 10:839-847. [PMID: 38921941 PMCID: PMC11209402 DOI: 10.3390/tomography10060064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 05/27/2024] [Accepted: 05/27/2024] [Indexed: 06/27/2024] Open
Abstract
The clinical magnetic resonance scanner (field strength ≤ 3.0 T) has limited efficacy in the high-resolution imaging of experimental mice. This study introduces a novel magnetic resonance micro-coil designed to enhance the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), thereby improving high-resolution imaging in experimental mice using clinical magnetic resonance scanners. Initially, a phantom was utilized to determine the maximum spatial resolution achievable by the novel micro-coil. Subsequently, 12 C57BL/6JGpt mice were included in this study, and the novel micro-coil was employed for their scanning. A clinical flexible coil was selected for comparative analysis. The scanning methodologies for both coils were consistent. The imaging clarity, noise, and artifacts produced by the two coils on mouse tissues and organs were subjectively evaluated, while the SNR and CNR of the brain, spinal cord, and liver were objectively measured. Differences in the images produced by the two coils were compared. The results indicated that the maximum spatial resolution of the novel micro-coil was 0.2 mm. Furthermore, the subjective evaluation of the images obtained using the novel micro-coil was superior to that of the flexible coil (p < 0.05). The SNR and CNR measurements for the brain, spinal cord, and liver using the novel micro-coil were significantly higher than those obtained with the flexible coil (p < 0.001). Our study suggests that the novel micro-coil is highly effective in enhancing the image quality of clinical magnetic resonance scanners in experimental mice.
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Affiliation(s)
- Xueke Qiu
- State Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016, China; (X.Q.); (Y.L.)
| | - Yang Liu
- State Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016, China; (X.Q.); (Y.L.)
| | - Fajin Lv
- State Key Laboratory of Ultrasound in Medicine and Engineering, College of Biomedical Engineering, Chongqing Medical University, Chongqing 400016, China; (X.Q.); (Y.L.)
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
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2
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Bhagavatula S, Cabeen R, Harris NG, Gröhn O, Wright DK, Garner R, Bennett A, Alba C, Martinez A, Ndode-Ekane XE, Andrade P, Paananen T, Ciszek R, Immonen R, Manninen E, Puhakka N, Tohka J, Heiskanen M, Ali I, Shultz SR, Casillas-Espinosa PM, Yamakawa GR, Jones NC, Hudson MR, Silva JC, Braine EL, Brady RD, Santana-Gomez CE, Smith GD, Staba R, O'Brien TJ, Pitkänen A, Duncan D. Image data harmonization tools for the analysis of post-traumatic epilepsy development in preclinical multisite MRI studies. Epilepsy Res 2023; 195:107201. [PMID: 37562146 PMCID: PMC10528111 DOI: 10.1016/j.eplepsyres.2023.107201] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 07/04/2023] [Accepted: 07/31/2023] [Indexed: 08/12/2023]
Abstract
Preclinical MRI studies have been utilized for the discovery of biomarkers that predict post-traumatic epilepsy (PTE). However, these single site studies often lack statistical power due to limited and homogeneous datasets. Therefore, multisite studies, such as the Epilepsy Bioinformatics Study for Antiepileptogenic Therapy (EpiBioS4Rx), are developed to create large, heterogeneous datasets that can lead to more statistically significant results. EpiBioS4Rx collects preclinical data internationally across sites, including the United States, Finland, and Australia. However, in doing so, there are robust normalization and harmonization processes that are required to obtain statistically significant and generalizable results. This work describes the tools and procedures used to harmonize multisite, multimodal preclinical imaging data acquired by EpiBioS4Rx. There were four main harmonization processes that were utilized, including file format harmonization, naming convention harmonization, image coordinate system harmonization, and diffusion tensor imaging (DTI) metrics harmonization. By using Python tools and bash scripts, the file formats, file names, and image coordinate systems are harmonized across all the sites. To harmonize DTI metrics, values are estimated for each voxel in an image to generate a histogram representing the whole image. Then, the Quantitative Imaging Toolkit (QIT) modules are utilized to scale the mode to a value of one and depict the subsequent harmonized histogram. The standardization of file formats, naming conventions, coordinate systems, and DTI metrics are qualitatively assessed. The histograms of the DTI metrics were generated for all the individual rodents per site. For inter-site analysis, an average of the individual scans was calculated to create a histogram that represents each site. In order to ensure the analysis can be run at the level of individual animals, the sham and TBI cohort were analyzed separately, which depicted the same harmonization factor. The results demonstrate that these processes qualitatively standardize the file formats, naming conventions, coordinate systems, and DTI metrics of the data. This assists in the ability to share data across the study, as well as disseminate tools that can help other researchers to strengthen the statistical power of their studies and analyze data more cohesively.
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Affiliation(s)
- Sweta Bhagavatula
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA.
| | - Ryan Cabeen
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Neil G Harris
- Department of Neurology, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, CA, USA
| | - Olli Gröhn
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - David K Wright
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Rachael Garner
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Alexis Bennett
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Celina Alba
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | - Aubrey Martinez
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
| | | | - Pedro Andrade
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Tomi Paananen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Robert Ciszek
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Riikka Immonen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Eppu Manninen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Noora Puhakka
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jussi Tohka
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Mette Heiskanen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Idrish Ali
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Sandy R Shultz
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Pablo M Casillas-Espinosa
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Glenn R Yamakawa
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Nigel C Jones
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Matthew R Hudson
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Juliana C Silva
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Emma L Braine
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Rhys D Brady
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Cesar E Santana-Gomez
- Department of Neurology, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, CA, USA
| | - Gregory D Smith
- Department of Neurology, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, CA, USA
| | - Richard Staba
- Department of Neurology, David Geffen School of Medicine at University of California at Los Angeles, Los Angeles, CA, USA
| | - Terence J O'Brien
- Departments of Neuroscience and Neurology, Central Clinical School, Alfred Health, Monash University, Melbourne, Victoria, Australia
| | - Asla Pitkänen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Dominique Duncan
- USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA
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3
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Huang CFJ, Lin WL, Hwang SC, Yao C, Chang H, Chen YY, Kuo LW. A feasibility study of wireless inductively coupled surface coil for MR-guided high-intensity focused ultrasound ablation of rodents on clinical MRI systems. Sci Rep 2022; 12:21907. [PMID: 36536022 PMCID: PMC9763396 DOI: 10.1038/s41598-022-26452-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
Recently, to conduct preclinical imaging research on clinical MRI systems has become an attractive alternative to researchers due to its wide availability, cost, and translational application to clinical human studies when compared to dedicated small animal, high-field preclinical MRI. However, insufficient signal-to-noise ratio (SNR) significantly degrades the applicability of those applications which require high SNR, e.g. magnetic resonance guided high-intensity focused ultrasound (MRgHIFU) treatment. This study introduces a wireless inductively coupled surface (WICS) coil design used on a clinical 3 T MRI system for MRgHIFU ablation. To evaluate the SNR improvement and temperature accuracy of WICS coil, the ex vivo experiments were performed on the pork tenderloins (n = 7) and the hind legs of deceased Sprague-Dawley rats (n = 5). To demonstrate the feasibility, the in vivo experiments were performed on the hind leg of Sprague-Dawley rat (n = 1). For all experiments, temperature measurements were performed before and during HIFU ablation. Temperature curves with and without WICS coil were compared to evaluate the temperature precision in ex vivo experiments. The use of WICS coil improves the temperature accuracy from 0.85 to 0.14 °C, demonstrating the feasibility of performing small animal MRgHIFU experiments using clinical 3 T MRI system with WICS coil.
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Affiliation(s)
- Chien-Feng Judith Huang
- grid.19188.390000 0004 0546 0241Department of Biomedical Engineering, National Taiwan University, Taipei, 100233 Taiwan ,grid.59784.370000000406229172Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, 35053 Taiwan
| | - Win-Li Lin
- grid.19188.390000 0004 0546 0241Department of Biomedical Engineering, National Taiwan University, Taipei, 100233 Taiwan ,grid.59784.370000000406229172Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, 35053 Taiwan
| | - San-Chao Hwang
- MBInsight Technology Corporation, New Taipei City, 236658 Taiwan
| | - Ching Yao
- MBInsight Technology Corporation, New Taipei City, 236658 Taiwan
| | - Hsu Chang
- MBInsight Technology Corporation, New Taipei City, 236658 Taiwan
| | - Yung-Yaw Chen
- grid.19188.390000 0004 0546 0241Department of Electrical Engineering, National Taiwan University, Taipei, 100233 Taiwan
| | - Li-Wei Kuo
- grid.59784.370000000406229172Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli, 35053 Taiwan ,grid.19188.390000 0004 0546 0241Institute of Medical Device and Imaging, National Taiwan University, Taipei, 100233 Taiwan
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4
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Chen Q, Luo C, Tie C, Cheng C, Zou C, Zhang X, Liu X, Zheng H, Li Y. A 5‐channel local B
0
shimming coil combined with a 3‐channel RF receiver coil for rat brain imaging at 3 T. Magn Reson Med 2022; 89:477-486. [DOI: 10.1002/mrm.29458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/22/2022] [Accepted: 08/22/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Qiaoyan Chen
- Paul C. Lauterbur Research Center for Biomedical Imaging Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences Shenzhen China
- Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong Province Shenzhen China
| | - Chao Luo
- Paul C. Lauterbur Research Center for Biomedical Imaging Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences Shenzhen China
- Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong Province Shenzhen China
| | - Changjun Tie
- Institute of Computing Technology, Chinese Academy of Sciences Beijing China
- University of Chinese Academy of Sciences Beijing China
- Peng Cheng Laboratory Shenzhen China
| | - Chuanli Cheng
- Paul C. Lauterbur Research Center for Biomedical Imaging Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences Shenzhen China
- Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong Province Shenzhen China
| | - Chao Zou
- Paul C. Lauterbur Research Center for Biomedical Imaging Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences Shenzhen China
- Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong Province Shenzhen China
| | - Xiaoliang Zhang
- Department of Biomedical Engineering State University of New York at Buffalo Buffalo New York USA
| | - Xin Liu
- Paul C. Lauterbur Research Center for Biomedical Imaging Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences Shenzhen China
- Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong Province Shenzhen China
| | - Hairong Zheng
- Paul C. Lauterbur Research Center for Biomedical Imaging Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences Shenzhen China
- Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong Province Shenzhen China
| | - Ye Li
- Paul C. Lauterbur Research Center for Biomedical Imaging Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences Shenzhen China
- Key Laboratory for Magnetic Resonance and Multimodality Imaging of Guangdong Province Shenzhen China
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5
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Generation of Synthetic Rat Brain MRI Scans with a 3D Enhanced Alpha Generative Adversarial Network. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12104844] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Translational brain research using Magnetic Resonance Imaging (MRI) is becoming increasingly popular as animal models are an essential part of scientific studies and more ultra-high-field scanners are becoming available. Some disadvantages of MRI are the availability of MRI scanners and the time required for a full scanning session. Privacy laws and the 3Rs ethics rule also make it difficult to create large datasets for training deep learning models. To overcome these challenges, an adaptation of the alpha Generative Adversarial Networks (GANs) architecture was used to test its ability to generate realistic 3D MRI scans of the rat brain in silico. As far as the authors are aware, this was the first time a GAN-based approach was used to generate synthetic MRI data of the rat brain. The generated scans were evaluated using various quantitative metrics, a Turing test, and a segmentation test. The last two tests proved the realism and applicability of the generated scans to real problems. Therefore, by using the proposed new normalisation layer and loss functions, it was possible to improve the realism of the generated rat MRI scans, and it was shown that using the generated data improved the segmentation model more than using the conventional data augmentation.
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6
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Iñigo-Marco I, Istúriz J, Fernández M, Nicolas MJ, Domínguez P, Bastarrika G, Valencia M, Fernández-Seara MA. Imaging of Stroke in Rodents Using a Clinical Scanner and Inductively Coupled Specially Designed Receiver Coils. Ann Biomed Eng 2021; 49:746-756. [PMID: 32918104 DOI: 10.1007/s10439-020-02610-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 09/02/2020] [Indexed: 11/26/2022]
Abstract
Imaging of small laboratory animals in clinical MRI scanners is feasible but challenging. Compared with dedicated preclinical systems, clinical scanners have relatively low B0 field (1.5-3.0 T) and gradient strength (40-60 mT/m). This work explored the use of wireless inductively coupled coils (ICCs) combined with appropriate pulse sequence parameters to overcome these two drawbacks, with a special emphasis on the optimization of the coil passive detuning circuit for this application. A Bengal rose photothrombotic stroke model was used to induce cortical infarction in rats and mice. Animals were imaged in a 3T scanner using T2 and T1-weighted sequences. In all animals, the ICCs allowed acquisition of high-quality images of the infarcted brain at acute and chronic stages. Images obtained with the ICCs showed a substantial increase in SNR compared to clinical coils (by factors of 6 in the rat brain and 16-17 in the mouse brain), and the absence of wires made the animal preparation workflow straightforward.
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Affiliation(s)
- Ignacio Iñigo-Marco
- Neuroscience Program, CIMA, University of Navarra, Pamplona, Spain
- IdiSNA, Navarra Institute for Health Research, Pamplona, Spain
| | | | - Miguel Fernández
- Radiology Department, Clínica Universidad de Navarra, Pio XII, 36, 31008, Pamplona, Spain
| | - Maria J Nicolas
- Neuroscience Program, CIMA, University of Navarra, Pamplona, Spain
- IdiSNA, Navarra Institute for Health Research, Pamplona, Spain
| | - Pablo Domínguez
- IdiSNA, Navarra Institute for Health Research, Pamplona, Spain
- Radiology Department, Clínica Universidad de Navarra, Pio XII, 36, 31008, Pamplona, Spain
| | - Gorka Bastarrika
- IdiSNA, Navarra Institute for Health Research, Pamplona, Spain
- Radiology Department, Clínica Universidad de Navarra, Pio XII, 36, 31008, Pamplona, Spain
| | - Miguel Valencia
- Neuroscience Program, CIMA, University of Navarra, Pamplona, Spain
- IdiSNA, Navarra Institute for Health Research, Pamplona, Spain
| | - María A Fernández-Seara
- IdiSNA, Navarra Institute for Health Research, Pamplona, Spain.
- Radiology Department, Clínica Universidad de Navarra, Pio XII, 36, 31008, Pamplona, Spain.
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7
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Müller J, Schürer M, Neubert C, Tillner F, Beyreuther E, Suckert T, Peters N, von Neubeck C, Lühr A, Krause M, Bütof R, Dietrich A. Multi-modality bedding platform for combined imaging and irradiation of mice. Biomed Phys Eng Express 2020; 6:037003. [PMID: 33438682 DOI: 10.1088/2057-1976/ab79f1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Preclinical imaging and irradiation yields valuable insights into clinically relevant research topics. While complementary imaging methods such as computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) can be combined within single devices, this is technically demanding and cost-intensive. Similarly, bedding and setup solutions are often specific to certain devices and research questions. We present a bedding platform for mice that is compatible with various preclinical imaging modalities (combined PET/MRI, cone beam CT) and irradiation with photons and protons. It consists of a 3D-printed bedding unit (acrylonitrile butadiene styrene, ABS) holding the animal and features an inhalation anesthesia mask, jaw fixation, ear pins, and immobilization for the hind leg. It can be embedded on mounting adaptors for multi-modal imaging and into a transport box (polymethyl methacrylate, PMMA) for experiments outside dedicated animal facilities while maintaining the animal's hygiene status. A vital support unit provides heating, inhalation anesthesia, and a respiration monitor. We dosimetrically evaluated used materials in order to assess their interaction with incident irradiation. Proof-of-concept multi-modal imaging protocols were used on phantoms and mice. The measured attenuation of the bedding unit for 40/60/80/200 kV X-rays was less than 3%. The measured stopping-power-ratio of ABS was 0.951, the combined water-equivalent thickness of bedding unit and transport box was 4.2 mm for proton energies of 150 MeV and 200 MeV. Proof-of-concept imaging showed no loss of image quality. Imaging data of individual mice from different imaging modalities could be aligned rigidly. The presented bed aims to provide a platform for experiments related to both multi-modal imaging and irradiation, thus offering the possibility for image-guided irradiation which relies on precise imaging and positioning. The usage as a self-contained, stand-alone unit outside dedicated animal facilities represents an advantage over setups designed for specific devices.
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Affiliation(s)
- Johannes Müller
- OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany. Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Institute of Radiooncology-OncoRay, Germany
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8
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Fiordelisi MF, Cavaliere C, Auletta L, Basso L, Salvatore M. Magnetic Resonance Imaging for Translational Research in Oncology. J Clin Med 2019; 8:jcm8111883. [PMID: 31698697 PMCID: PMC6912299 DOI: 10.3390/jcm8111883] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 10/28/2019] [Accepted: 10/29/2019] [Indexed: 12/19/2022] Open
Abstract
The translation of results from the preclinical to the clinical setting is often anything other than straightforward. Indeed, ideas and even very intriguing results obtained at all levels of preclinical research, i.e., in vitro, on animal models, or even in clinical trials, often require much effort to validate, and sometimes, even useful data are lost or are demonstrated to be inapplicable in the clinic. In vivo, small-animal, preclinical imaging uses almost the same technologies in terms of hardware and software settings as for human patients, and hence, might result in a more rapid translation. In this perspective, magnetic resonance imaging might be the most translatable technique, since only in rare cases does it require the use of contrast agents, and when not, sequences developed in the lab can be readily applied to patients, thanks to their non-invasiveness. The wide range of sequences can give much useful information on the anatomy and pathophysiology of oncologic lesions in different body districts. This review aims to underline the versatility of this imaging technique and its various approaches, reporting the latest preclinical studies on thyroid, breast, and prostate cancers, both on small laboratory animals and on human patients, according to our previous and ongoing research lines.
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9
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Chrzanowski SM, Vohra RS, Lee-McMullen BA, Batra A, Spradlin RA, Morales J, Forbes S, Vandenborne K, Barton ER, Walter GA. Contrast-Enhanced Near-Infrared Optical Imaging Detects Exacerbation and Amelioration of Murine Muscular Dystrophy. Mol Imaging 2018; 16:1536012117732439. [PMID: 29271299 PMCID: PMC5985549 DOI: 10.1177/1536012117732439] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Assessment of muscle pathology is a key outcome measure to measure the success of
clinical trials studying muscular dystrophies; however, few robust minimally invasive
measures exist. Indocyanine green (ICG)-enhanced near-infrared (NIR) optical imaging
offers an objective, minimally invasive, and longitudinal modality that can quantify
pathology within muscle by imaging uptake of ICG into the damaged muscles. Dystrophic mice
lacking dystrophin (mdx) or gamma-sarcoglycan (Sgcg−/−) were compared to
control mice by NIR optical imaging and magnetic resonance imaging (MRI). We determined
that optical imaging could be used to differentiate control and dystrophic mice, visualize
eccentric muscle induced by downhill treadmill running, and restore the membrane integrity
in Sgcg−/− mice following adeno-associated virus (AAV) delivery of recombinant
human SGCG (desAAV8hSGCG). We conclude that NIR optical imaging is comparable to MRI and
can be used to detect muscle damage in dystrophic muscle as compared to unaffected
controls, monitor worsening of muscle pathology in muscular dystrophy, and assess
regression of pathology following therapeutic intervention in muscular dystrophies.
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Affiliation(s)
- Stephen M Chrzanowski
- 1 Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL, USA
| | - Ravneet S Vohra
- 1 Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL, USA
| | | | - Abhinandan Batra
- 3 Department of Physical Therapy, University of Florida, Gainesville, FL, USA
| | - Ray A Spradlin
- 4 Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - Jazmine Morales
- 4 Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - Sean Forbes
- 3 Department of Physical Therapy, University of Florida, Gainesville, FL, USA
| | - Krista Vandenborne
- 3 Department of Physical Therapy, University of Florida, Gainesville, FL, USA
| | - Elisabeth R Barton
- 4 Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA
| | - Glenn A Walter
- 1 Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL, USA
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10
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Monitoring disease activity noninvasively in the mdx model of Duchenne muscular dystrophy. Proc Natl Acad Sci U S A 2018; 115:7741-7746. [PMID: 29987034 DOI: 10.1073/pnas.1802425115] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a rare, muscle degenerative disease resulting from the absence of the dystrophin protein. DMD is characterized by progressive loss of muscle fibers, muscle weakness, and eventually loss of ambulation and premature death. Currently, there is no cure for DMD and improved methods of disease monitoring are crucial for the development of novel treatments. In this study, we describe a new method of assessing disease progression noninvasively in the mdx model of DMD. The reporter mice, which we term the dystrophic Degeneration Reporter strains, contain an inducible CRE-responsive luciferase reporter active in mature myofibers. In these mice, muscle degeneration is reflected in changes in the level of luciferase expression, which can be monitored using noninvasive, bioluminescence imaging. We monitored the natural history and disease progression in these dystrophic report mice and found that decreases in luciferase signals directly correlated with muscle degeneration. We further demonstrated that this reporter strain, as well as a previously reported Regeneration Reporter strain, successfully reveals the effectiveness of a gene therapy treatment following systemic administration of a recombinant adeno-associated virus-6 (rAAV-6) encoding a microdystrophin construct. Our data demonstrate the value of these noninvasive imaging modalities for monitoring disease progression and response to therapy in mouse models of muscular dystrophy.
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11
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Jerome NP, Boult JKR, Orton MR, d'Arcy JA, Nerurkar A, Leach MO, Koh DM, Collins DJ, Robinson SP. Characterisation of fibrosis in chemically-induced rat mammary carcinomas using multi-modal endogenous contrast MRI on a 1.5T clinical platform. Eur Radiol 2018; 28:1642-1653. [PMID: 29038934 PMCID: PMC5834566 DOI: 10.1007/s00330-017-5083-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 08/25/2017] [Accepted: 09/14/2017] [Indexed: 12/17/2022]
Abstract
OBJECTIVES To determine the ability of multi-parametric, endogenous contrast MRI to detect and quantify fibrosis in a chemically-induced rat model of mammary carcinoma. METHODS Female Sprague-Dawley rats (n=18) were administered with N-methyl-N-nitrosourea; resulting mammary carcinomas underwent nine-b-value diffusion-weighted (DWI), ultrashort-echo (UTE) and magnetisation transfer (MT) magnetic resonance imaging (MRI) on a clinical 1.5T platform, and associated quantitative MR parameters were calculated. Excised tumours were histologically assessed for degree of necrosis, collagen, hypoxia and microvessel density. Significance level adjusted for multiple comparisons was p=0.0125. RESULTS Significant correlations were found between MT parameters and degree of picrosirius red staining (r > 0.85, p < 0.0002 for ka and δ, r < -0.75, p < 0.001 for T1 and T1s, Pearson), indicating that MT is sensitive to collagen content in mammary carcinoma. Picrosirius red also correlated with the DWI parameter fD* (r=0.801, p=0.0004) and conventional gradient-echo T2* (r=-0.660, p=0.0055). Percentage necrosis correlated moderately with ultrashort/conventional-echo signal ratio (r=0.620, p=0.0105). Pimonidazole adduct (hypoxia) and CD31 (microvessel density) staining did not correlate with any MR parameter assessed. CONCLUSIONS Magnetisation transfer MRI successfully detects collagen content in mammary carcinoma, supporting inclusion of MT imaging to identify fibrosis, a prognostic marker, in clinical breast MRI examinations. KEY POINTS • Magnetisation transfer imaging is sensitive to collagen content in mammary carcinoma. • Magnetisation transfer imaging to detect fibrosis in mammary carcinoma fibrosis is feasible. • IVIM diffusion does not correlate with microvessel density in preclinical mammary carcinoma.
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Affiliation(s)
- Neil P Jerome
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, SM2 5NG, UK
| | - Jessica K R Boult
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, SM2 5NG, UK
| | - Matthew R Orton
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, SM2 5NG, UK
| | - James A d'Arcy
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, SM2 5NG, UK
| | - Ashutosh Nerurkar
- Department of Histopathology, Royal Marsden NHS Foundation Trust, London, SW3 6JJ, UK
| | - Martin O Leach
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, SM2 5NG, UK
| | - Dow-Mu Koh
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, SM2 5NG, UK
- Department of Radiology, Royal Marsden NHS Foundation Trust, London, SM2 5PT, UK
| | - David J Collins
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, SM2 5NG, UK
| | - Simon P Robinson
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, SM2 5NG, UK.
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12
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Felder J, Celik AA, Choi CH, Schwan S, Shah NJ. 9.4 T small animal MRI using clinical components for direct translational studies. J Transl Med 2017; 15:264. [PMID: 29282070 PMCID: PMC5745792 DOI: 10.1186/s12967-017-1373-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 12/19/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Magnetic resonance is a major preclinical and clinical imaging modality ideally suited for longitudinal studies, e.g. in pharmacological developments. The lack of a proven platform that maintains an identical imaging protocol between preclinical and clinical platforms is solved with the construction of an animal scanner based on clinical hard- and software. METHODS A small animal magnet and gradient system were connected to a clinical MR system. Several hardware components were either modified or built in-house to achieve compatibility. The clinical software was modified to account for the different field-of-view of a preclinical MR system. The established scanner was evaluated using clinical QA protocols, and platform compatibility for translational research was verified against clinical scanners of different field strength. RESULTS The constructed animal scanner operates with the majority of clinical imaging sequences. Translational research is greatly facilitated as protocols can be shared between preclinical and clinical platforms. Hence, when maintaining sequences parameters, maximum similarity between pulses played out on a human or an animal system is maintained. CONCLUSION Coupling of a small animal magnet with a clinical MR system is a flexible, easy to use way to establish and advance translational imaging capability. It provides cost and labor efficient translational capability as no tedious sequence reprogramming between moieties is required and cross-platform compatibility of sequences facilitates multi-center studies.
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Affiliation(s)
- Jörg Felder
- Institute of Neuroscience and Medicine-4, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - A. Avdo Celik
- Institute of Neuroscience and Medicine-11, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Chang-Hoon Choi
- Institute of Neuroscience and Medicine-4, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Stefan Schwan
- Institute of Neuroscience and Medicine-4, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - N. Jon Shah
- Institute of Neuroscience and Medicine-4, Forschungszentrum Jülich, 52425 Jülich, Germany
- Institute of Neuroscience and Medicine-11, Forschungszentrum Jülich, 52425 Jülich, Germany
- Faculty of Medicine, Department of Neurology, JARA, RWTH Aachen University, 52074 Aachen, Germany
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13
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Jansen CHP, Brangsch J, Reimann C, Adams L, Hamm B, Botnar RM, Makowski MR. In Vivo High-Frequency Ultrasound for the Characterization of Thrombi Associated with Aortic Aneurysms in an Experimental Mouse Model. ULTRASOUND IN MEDICINE & BIOLOGY 2017; 43:2882-2890. [PMID: 28965722 DOI: 10.1016/j.ultrasmedbio.2017.08.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 08/07/2017] [Accepted: 08/09/2017] [Indexed: 06/07/2023]
Abstract
The development of abdominal aortic aneurysm (AAA) associated thrombi plays an important role during the onset and progression of AAAs. The aim of this study was to evaluate the potential of high-frequency ultrasound for characterization of AAA associated thrombi in an apolipoprotein-E-deficient mouse-model. Ultrasound measurements were performed using a high-resolution ultrasound system (Vevo770, FUJIFILM VisualSonics, Inc., Toronto, ON, Canada) with a 30 MHz linear-array transducer (RMV707 B). Magnetic resonance imaging with a 3 Tesla scanner (Achieva MR system, Philips Healthcare, Best, The Netherlands) and a single-loop microscopy coil was performed as a reference standard. All stages of aneurysm development were evaluated by histologic analyses. The "signal-thrombus-matrix" to "signal-blood" ratio on high-frequency ultrasound measurements showed a strong correlation (R2 = 0.81, p <0.05) with the state of extracellular matrix remodeling. Furthermore, size measurements derived from the high-frequency ultrasound correlated well with magnetic resonance imaging and histology. This study demonstrated that high-frequency ultrasound enables the reliable in vivo quantification of extracellular matrix remodeling at various stages of thrombus development, based on the thrombus echogenicity.
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Affiliation(s)
| | | | | | - Lisa Adams
- Department of Radiology, Charité, Berlin, Germany
| | - Bernd Hamm
- Department of Radiology, Charité, Berlin, Germany
| | - Rene M Botnar
- Division of Imaging Sciences, King's College London, London, United Kingdom; BHF Centre of Excellence, King's College London, London, United Kingdom; Cardioascular Division, King's College London, London, United Kingdom; Wellcome Trust and EPSRC Medical Engineering Center, King's College London, London, United Kingdom; NIHR Biomedical Research Centre, King's College London, London, United Kingdom
| | - Marcus R Makowski
- Division of Imaging Sciences, King's College London, London, United Kingdom; Department of Radiology, Charité, Berlin, Germany
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14
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Almeida GS, Panek R, Hallsworth A, Webber H, Papaevangelou E, Boult JKR, Jamin Y, Chesler L, Robinson SP. Pre-clinical imaging of transgenic mouse models of neuroblastoma using a dedicated 3-element solenoid coil on a clinical 3T platform. Br J Cancer 2017; 117:791-800. [PMID: 28787429 PMCID: PMC5589996 DOI: 10.1038/bjc.2017.251] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/04/2017] [Accepted: 07/06/2017] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND The use of clinical MRI scanners to conduct pre-clinical research facilitates comparisons with clinical studies. Here the utility and sensitivity of anatomical and functional MRI data/biomarkers acquired from transgenic mouse models of neuroblastoma using a dedicated radiofrequency (RF) coil on a clinical 3T scanner was evaluated. METHODS Multiparametric MRI of transgenic mice bearing abdominal neuroblastomas was performed at 3T, and data cross-referenced to that acquired from the same mice on a pre-clinical 7T MRI system. T2-weighted imaging, quantitation of the native longitudinal relaxation time (T1) and the transverse relaxation rate (R2*), and dynamic contrast-enhanced (DCE)-MRI, was used to assess tumour volume, phenotype and response to cyclophosphamide or cabozantinib. RESULTS Excellent T2-weighted image contrast enabled clear tumour delineation at 3T. Significant correlations of tumour volume (R=0.98, P<0.0001) and R2* (R=0.87, P<0.002) measured at 3 and 7T were established. Mice with neuroblastomas harbouring the anaplastic lymphoma kinase mutation exhibited a significantly slower R2* (P<0.001), consistent with impaired tumour perfusion. DCE-MRI was performed simultaneously on three transgenic mice, yielding estimates of Ktrans for each tumour (median Ktrans values of 0.202, 0.168 and 0.114 min-1). Cyclophosphamide elicited a significant reduction in both tumour burden (P<0.002) and native T1 (P<0.01), whereas cabozantinib induced significant (P<0.01) tumour growth delay. CONCLUSIONS Simultaneous multiparametric MRI of multiple tumour-bearing animals using this coil arrangement at 3T can provide high efficiency/throughput for both phenotypic characterisation and evaluation of novel therapeutics, and facilitate the introduction of functional MRI biomarkers into aligned imaging-embedded clinical trials.
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Affiliation(s)
- Gilberto S Almeida
- Division of Radiotherapy & Imaging, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey SM2 5NG, UK
| | - Rafal Panek
- Division of Radiotherapy & Imaging, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey SM2 5NG, UK
| | - Albert Hallsworth
- Division of Clinical Studies, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey, SM2 5NG, UK
| | - Hannah Webber
- Division of Clinical Studies, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey, SM2 5NG, UK
| | - Efthymia Papaevangelou
- Division of Radiotherapy & Imaging, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey SM2 5NG, UK
| | - Jessica KR Boult
- Division of Radiotherapy & Imaging, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey SM2 5NG, UK
| | - Yann Jamin
- Division of Radiotherapy & Imaging, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey SM2 5NG, UK
| | - Louis Chesler
- Division of Clinical Studies, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey, SM2 5NG, UK
| | - Simon P Robinson
- Division of Radiotherapy & Imaging, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey SM2 5NG, UK
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15
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Brangsch J, Reimann C, Collettini F, Buchert R, Botnar RM, Makowski MR. Molecular Imaging of Abdominal Aortic Aneurysms. Trends Mol Med 2017; 23:150-164. [PMID: 28110838 DOI: 10.1016/j.molmed.2016.12.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/06/2016] [Accepted: 12/11/2016] [Indexed: 12/21/2022]
Abstract
Abdominal aortic aneurysms (AAAs) represent a vascular disease with severe complications. AAAs are currently the overall 10th leading cause of death in western countries and their incidence is rising. Although different diagnostic techniques are currently available in clinical practice, including ultrasound (US), magnetic resonance imaging (MRI), and computed tomography (CT), imaging-based prediction of life-threatening complications such as aneurysm-rupture remains challenging. Molecular imaging provides a novel diagnostic approach for in vivo visualization of biological processes and pathological alterations at a cellular and molecular level. Its overall aim is to improve our understanding of disease pathogenesis and to facilitate novel diagnostic pathways. This review outlines recent preclinical and clinical developments in molecular MRI, positron emission tomography (PET), and single-photon emission computed tomography (SPECT) for imaging of AAAs.
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Affiliation(s)
- Julia Brangsch
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Carolin Reimann
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Federico Collettini
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Ralf Buchert
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - René M Botnar
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany; Division of Imaging Sciences and Biomedical Engineering, King's College London, London WC2R 2LS, UK; Wellcome Trust and Engineering and Physical Sciences Research Council (EPSRC) Medical Engineering Centre, King's College London, London SE1 7EH, UK; British Heart Foundation (BHF) Centre of Excellence, King's College London, London SE5 9NU, UK; National Institute for Health Research (NIHR) Biomedical Research Centre, King's College London, London SE1 9RT, UK
| | - Marcus R Makowski
- Department of Radiology, Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany; Division of Imaging Sciences and Biomedical Engineering, King's College London, London WC2R 2LS, UK.
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17
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Chrzanowski SM, Batra A, Lee-McMullen B, Vohra RS, Forbes SC, Jiang H, Vandenborne K, Walter GA. Near-Infrared Optical Imaging Noninvasively Detects Acutely Damaged Muscle. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:2692-700. [PMID: 27565039 DOI: 10.1016/j.ajpath.2016.06.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 05/28/2016] [Accepted: 06/08/2016] [Indexed: 12/01/2022]
Abstract
Muscle damage is currently assessed through methods such as muscle biopsy, serum biomarkers, functional testing, and imaging procedures, each with its own inherent limitations, and a pressing need for a safe, repeatable, inexpensive, and noninvasive modality to assess the state of muscle health remains. Our aim was to develop and assess near-infrared (NIR) optical imaging as a novel noninvasive method of detecting and quantifying muscle damage. An immobilization-reambulation model was used for inducing muscle damage and recovery in the lower hindlimbs in mice. Confirmation of muscle damage was obtained using in vivo indocyanine green-enhanced NIR optical imaging, magnetic resonance imaging, and ex vivo tissue analysis. The soleus of the immobilized-reambulated hindlimb was found to have a greater amount of muscle damage compared to that in the contralateral nonimmobilized limb, confirmed by in vivo indocyanine green-enhanced NIR optical imaging (3.86-fold increase in radiant efficiency), magnetic resonance imaging (1.41-fold increase in T2), and an ex vivo spectrophotometric assay of indocyanine green uptake (1.87-fold increase in normalized absorbance). Contrast-enhanced NIR optical imaging provides a sensitive, rapid, and noninvasive screening method that can be used for imaging and quantifying muscle damage and recovery in vivo.
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Affiliation(s)
- Stephen M Chrzanowski
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida
| | - Abhinandan Batra
- Department of Physical Therapy, University of Florida, Gainesville, Florida
| | | | - Ravneet S Vohra
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida
| | - Sean C Forbes
- Department of Physical Therapy, University of Florida, Gainesville, Florida
| | - Huabei Jiang
- Department of Biomedical Engineering, University of Florida, Gainesville, Florida
| | - Krista Vandenborne
- Department of Physical Therapy, University of Florida, Gainesville, Florida
| | - Glenn A Walter
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, Florida.
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18
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Kirschner S, Felix MC, Hartmann L, Bierbaum M, Maros ME, Kerl HU, Wenz F, Glatting G, Kramer M, Giordano FA, Brockmann MA. In vivo micro-CT imaging of untreated and irradiated orthotopic glioblastoma xenografts in mice: capabilities, limitations and a comparison with bioluminescence imaging. J Neurooncol 2015; 122:245-54. [PMID: 25605299 DOI: 10.1007/s11060-014-1708-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 12/24/2014] [Indexed: 11/28/2022]
Abstract
Small animal imaging is of increasing relevance in biomedical research. Studies systematically assessing the diagnostic accuracy of contrast-enhanced in vivo micro-CT of orthotopic glioma xenografts in mice do not exist. NOD/SCID/γc(-/-) mice (n = 27) underwent intracerebral implantation of 2.5 × 10(6) GFP-Luciferase-transduced U87MG cells. Mice underwent bioluminescence imaging (BLI) to detect tumor growth and afterwards repeated contrast-enhanced (300 µl Iomeprol i.v.) micro-CT imaging (80 kV, 75 µAs, 360° rotation, 1,000 projections, 33 s scan time, resolution 40 × 40 × 53 µm, 0.5 Gy/scan). Presence of tumors, tumor diameter and tumor volume in micro-CT were rated by two independent readers. Results were compared with histological analyses. Six mice with tumors confirmed by micro-CT received fractionated irradiation (3 × 5 Gy every other day) using the micro-CT (5 mm pencil beam geometry). Repeated micro-CT scans were tolerated well. Tumor engraftment rate was 74 % (n = 20). In micro-CT, mean tumor volume was 30 ± 33 mm(3), and the smallest detectable tumor measured 360 × 620 µm. The inter-rater agreement (n = 51 micro-CT scans) for the item tumor yes/no was excellent (Spearman-Rho = 0.862, p < 0.001). Sensitivity and specificity of micro-CT were 0.95 and 0.71, respectively (PPV = 0.91, NPV = 0.83). BLI on day 21 after tumor implantation had a sensitivity and specificity of 0.90 and 1.0, respectively (PPV = 1.0, NPV = 0.5). Maximum tumor diameter and volume in micro-CT and histology correlated excellently (tumor diameter: 0.929, p < 0.001; tumor volume: 0.969, p < 0.001, n = 17). Irradiated animals showed a large central tumor necrosis. Longitudinal contrast enhanced micro-CT imaging of brain tumor growth in live mice is feasible at high sensitivity levels and with excellent inter-rater agreement and allows visualization of radiation effects.
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Affiliation(s)
- Stefanie Kirschner
- Department of Neuroradiology, Medical Faculty Mannheim, University, Medical Center Mannheim, Heidelberg University, 68167, Mannheim, Germany
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Wu L, Wang C, Yao X, Liu K, Xu Y, Zhang H, Fu C, Wang X, Li Y. Application of 3.0 tesla magnetic resonance imaging for diagnosis in the orthotopic nude mouse model of pancreatic cancer. Exp Anim 2014; 63:403-13. [PMID: 25048266 PMCID: PMC4244289 DOI: 10.1538/expanim.63.403] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The aim of this study was to successfully establish an orthotopic murine model using two
different human pancreatic adenocarcinoma cell lines and to propose a 3.0 tesla MRI
protocol for noninvasive characterization of this model. SW1990 and MIAPaca-2 tumor cells
were injected into the pancreas of BALB/C nu/nu mice. Tumor growth rate
and morphological information were assessed by 3.0 tesla MRI (T1WI, T2WI and DCE-MRI) and
immunohistology. Proliferation of SW1990 was significantly faster than that of MIAPaca-2
(P=0.000), but MIAPaca-2 mice had a significantly shorter survival than
SW1990 mice (41 days and 44 days respectively, P=0.027). MRI could
reliably monitor tumor growth in both cell lines: the tumors exhibiting a spherical growth
pattern showed a high-intensity signal, and the SW1990 group developed significantly
larger tumors compared with the MIAPaCa-2 group. There were no statistical differences
between the two groups in which tumor size was assessed using electronic calipers and an
MRI scan (P=0.680). Both tumors showed a slow gradual enhancement
pattern. Immunohistochemistry demonstrated tumor tissues showing high expression of Ki-67.
This model closely mimics human pancreatic cancer and permits monitoring of tumor growth
and morphological information by noninvasive 3.0 tesla MRI studies reducing the number of
mice required.
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Affiliation(s)
- Li Wu
- Department of Intervetional Radiology, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 20032, P.R.China
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20
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Meßner NM, Zöllner FG, Kalayciyan R, Schad LR. Pre-clinical functional Magnetic Resonance Imaging Part II: The heart. Z Med Phys 2014; 24:307-22. [PMID: 25023418 DOI: 10.1016/j.zemedi.2014.06.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 05/09/2014] [Accepted: 06/17/2014] [Indexed: 12/21/2022]
Abstract
One third of all deaths worldwide in 2008 were caused by cardiovascular diseases (CVD), and the incidence of CVD related deaths rises ever more. Thus, improved imaging techniques and modalities are needed for the evaluation of cardiac morphology and function. Cardiac magnetic resonance imaging (CMRI) is a minimally invasive technique that is increasingly important due to its high spatial and temporal resolution, its high soft tissue contrast and its ability of functional and quantitative imaging. It is widely accepted as the gold standard of cardiac functional analysis. In the short period of small animal MRI, remarkable progress has been achieved concerning new, fast imaging schemes as well as purpose-built equipment. Dedicated small animal scanners allow for tapping the full potential of recently developed animal models of cardiac disease. In this paper, we review state-of-the-art cardiac magnetic resonance imaging techniques and applications in small animals at ultra-high fields (UHF).
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Affiliation(s)
- Nadja M Meßner
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Frank G Zöllner
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
| | - Raffi Kalayciyan
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Lothar R Schad
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
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21
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WU L, WANG C, YAO X, LIU K, XU Y, ZHANG H, FU C, WANG X, LI Y. Application of 3.0 Tesla Magnetic Resonance Imaging for Diagnosis in the Orthotopic Nude Mouse Model of Pancreatic Cancer. Exp Anim 2014. [DOI: 10.1538/expanim.13-0086] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Affiliation(s)
- Li WU
- Department of Intervetional Radiology, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 20032, P.R.China
- Department of Radiology, Shanghai jiao Tong University Affiliated Sixth People’s Hospital. Shanghai, P.R.China
| | - Chen WANG
- Cancer Research Institute, Shanghai Cancer Center, Fudan University, 270 Dong An Road, Shanghai, 20032, P.R.China
| | - Xiuzhong YAO
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai, P.R.China
| | - Kai LIU
- Department of Radiology, Zhongshan Hospital, Fudan University, Shanghai, P.R.China
| | - Yanjun XU
- Research Institute of Health Development Strategies, Fudan University, Shanghai, P.R.China
| | - Haitao ZHANG
- Department of Protistology, Guangdong Jiaying Medical College, Meizhou, P.R.China
| | - Caixia FU
- Siemens Shenzhen Magnetic Resonance Ltd, Siemens MRI Center, Shenzhen, P.R.China
| | - Xiaolin WANG
- Department of Intervetional Radiology, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 20032, P.R.China
| | - Yingyi LI
- Cancer Research Institute, Shanghai Cancer Center, Fudan University, 270 Dong An Road, Shanghai, 20032, P.R.China
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Herrmann KH, Pfeiffer N, Krumbein I, Herrmann L, Reichenbach JR. MRI compatible small animal monitoring and trigger system for whole body scanners. Z Med Phys 2013; 24:55-64. [PMID: 23962379 DOI: 10.1016/j.zemedi.2013.07.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 07/16/2013] [Accepted: 07/16/2013] [Indexed: 02/03/2023]
Abstract
Performing magnetic resonance imaging (MRI) experiments with small animals requires continuous monitoring of vital parameters, especially the respiration rate. Clinical whole-body MR scanners represent an attractive option for preclinical imaging as dedicated animal scanners are cost-intensive in both investment and maintenance, thus limiting their availability. Even though impressive image quality is achievable with clinical MR systems in combination with special coils, their built-in physiologic monitoring and triggering units are often not suited for small animal imaging. In this work, we present a simple, MRI compatible low cost solution to monitor the respiration and heart rate of small animals in a clinical whole-body MR scanner. The recording and processing of the biosignals as well as the optimisation of the respiratory trigger generation is decribed. Additionally rat and mouse in-vivo MRI experiments are presented to illustrate the effectiveness of the monitoring and respiratory trigger system in suppressing motion artifacts.
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Affiliation(s)
- Karl-Heinz Herrmann
- Medical Physics Group, Institute for Diagnostic and Interventional Radiology I, Jena University Hospital, Philosophenweg 3, Gebäude 5, 07743 Jena, Germany.
| | - Norman Pfeiffer
- Medical Physics Group, Institute for Diagnostic and Interventional Radiology I, Jena University Hospital, Philosophenweg 3, Gebäude 5, 07743 Jena, Germany; Ernst-Abbe-Fachhochschule Jena, Carl-Zeiss-Promenade 2, 07745 Jena, Germany
| | - Ines Krumbein
- Medical Physics Group, Institute for Diagnostic and Interventional Radiology I, Jena University Hospital, Philosophenweg 3, Gebäude 5, 07743 Jena, Germany
| | - Lutz Herrmann
- Ernst-Abbe-Fachhochschule Jena, Carl-Zeiss-Promenade 2, 07745 Jena, Germany
| | - Jürgen R Reichenbach
- Medical Physics Group, Institute for Diagnostic and Interventional Radiology I, Jena University Hospital, Philosophenweg 3, Gebäude 5, 07743 Jena, Germany
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Mitsuda M, Yamaguchi M, Nakagami R, Furuta T, Sekine N, Niitsu M, Moriyama N, Fujii H. Intensity correction method customized for multi-animal abdominal MR imaging with 3T clinical scanner and multi-array coil. Magn Reson Med Sci 2013; 12:95-103. [PMID: 23666151 DOI: 10.2463/mrms.2012-0038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE Simultaneous magnetic resonance (MR) imaging of multiple small animals in a single session increases throughput of preclinical imaging experiments. Such imaging using a 3-tesla clinical scanner with multi-array coil requires correction of intensity variation caused by the inhomogeneous sensitivity profile of the coil. We explored a method for correcting intensity that we customized for multi-animal MR imaging, especially abdominal imaging. METHOD Our institutional committee for animal experimentation approved the protocol. We acquired high resolution T₁-, T₂-, and T₂*-weighted images and low resolution proton density-weighted images (PDWIs) of 4 rat abdomens simultaneously using a 3T clinical scanner and custom-made multi-array coil. For comparison, we also acquired T₁-, T₂-, and T₂*-weighted volume coil images in the same rats in 4 separate sessions. We used software created in-house to correct intensity variation. We applied thresholding to the PDWIs to produce binary images that displayed only a signal-producing area, calculated multi-array coil sensitivity maps by dividing low-pass filtered PDWIs by low-pass filtered binary images pixel by pixel, and divided uncorrected T₁-, T₂-, or T₂*-weighted images by those maps to obtain intensity-corrected images. We compared tissue contrast among the liver, spinal canal, and muscle between intensity-corrected multi-array coil images and volume coil images. RESULTS Our intensity correction method performed well for all pulse sequences studied and corrected variation in original multi-array coil images without deteriorating the throughput of animal experiments. Tissue contrasts were comparable between intensity-corrected multi-array coil images and volume coil images. CONCLUSION Our intensity correction method customized for multi-animal abdominal MR imaging using a 3T clinical scanner and dedicated multi-array coil could facilitate image interpretation.
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Affiliation(s)
- Minoru Mitsuda
- Functional Imaging Division, Research Center for Innovative Oncology, National Cancer Center Hospital East, Kashiwanoha 6-5-1, Kashiwa, Chiba 277-8577, Japan
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Redfern WS, Ewart LC, Lainée P, Pinches M, Robinson S, Valentin JP. Functional assessments in repeat-dose toxicity studies: the art of the possible. Toxicol Res (Camb) 2013. [DOI: 10.1039/c3tx20093k] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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Abstract
Molecular imaging fundamentally changes the way we look at cancer. Imaging paradigms are now shifting away from classical morphological measures towards the assessment of functional, metabolic, cellular, and molecular information in vivo. Interdisciplinary driven developments of imaging methodology and probe molecules utilizing animal models of human cancers have enhanced our ability to non-invasively characterize neoplastic tissue and follow anti-cancer treatments. Preclinical molecular imaging offers a whole palette of excellent methodology to choose from. We will focus on positron emission tomography (PET) and magnetic resonance imaging (MRI) techniques, since they provide excellent and complementary molecular imaging capabilities and bear high potential for clinical translation. Prerequisites and consequences of using animal models as surrogates of human cancers in preclinical molecular imaging are outlined. We present physical principles, values and limitations of PET and MRI as molecular imaging modalities and comment on their high potential to non-invasively assess information on hypoxia, angiogenesis, apoptosis, gene expression, metabolism, and cell trafficking in preclinical cancer research.
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Affiliation(s)
- Gunter Wolf
- University Hospital Carl Gustav Carus at the Technische Universität Dresden, Dresden, Germany.
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Yamaguchi M, Mitsuda M, Ezawa K, Nakagami R, Furuta T, Sekine N, Niitsu M, Fujii H. Artifact-reduced simultaneous MRI of multiple rats with liver cancer using PROPELLER. J Magn Reson Imaging 2012; 38:225-30. [PMID: 23238830 DOI: 10.1002/jmri.23969] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Accepted: 10/31/2012] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To explore simultaneous magnetic resonance imaging (MRI) for multiple hepatoma-bearing rats in a single session suppressing motion- and flow-related artifacts to conduct preclinical cancer research efficiently. MATERIALS AND METHODS Our institutional Animal Experimental Committee approved this study. We acquired PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) T2 - and diffusion-weighted images of the liver in one healthy and 11 N1-S1 hepatoma-bearing rats in three sessions using a 3-T clinical scanner and dedicated multiarray coil. We compared tumor volumes on MR images and those on specimens, evaluated apparent diffusion coefficients (ADC) of the tumor, and compared them to previously reported values. RESULTS Each MRI session took 39-50 minutes from anesthesia induction to the end of scans for four rats (10-13 minutes per rat). PROPELLER provided artifact-reduced T2 - and diffusion-weighted images of the rat livers. Tumor volumes on MR images ranged from 0.04-1.81 cm(3) and were highly correlated with those on specimens. The ADC was 1.57 ± 0.37 × 10(-3) mm(2) /s (average ± SD), comparable to previously reported values. CONCLUSION PROPELLER allowed simultaneous acquisition of artifact-reduced T2 - and diffusion-weighted images of multiple hepatoma-bearing rats. This technique can promote high-throughput preclinical MR research for liver cancer.
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Affiliation(s)
- Masayuki Yamaguchi
- Functional Imaging Division, Research Center for Innovative Oncology, National Cancer Center Hospital East, Kashiwa, Chiba, Japan.
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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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Mystkowska D, Tutas A, Jezierska-Woźniak K, Mikołajczyk A, Bobek-Billewicz B, Jurkowski M. Usefulness of clinical magnetic resonance scanners for imaging experimental changes in laboratory rodents' central nervous system. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.poamed.2012.04.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Botnar RM, Makowski MR. Cardiovascular magnetic resonance imaging in small animals. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 105:227-61. [PMID: 22137434 DOI: 10.1016/b978-0-12-394596-9.00008-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Noninvasive imaging studies involving small animals are becoming increasingly important in preclinical pharmacological, genetic, and biomedical cardiovascular research. Especially small animal magnetic resonance imaging (MRI) using high field and clinical MRI systems has gained significant importance in recent years. Compared to other imaging modalities, like computer tomography, MRI can provide an excellent soft tissue contrast, which enables the characterization of different kinds of tissues without the use of contrast agents. In addition, imaging can be performed with high spatial and temporal resolution. Small animal MRI cannot only provide anatomical information about the beating murine heart; it can also provide functional and molecular information, which makes it a unique imaging modality. Compared to clinical MRI examinations in humans, small animal MRI is associated with additional challenges. These included a smaller size of all cardiovascular structures and a up to ten times higher heart rate. Dedicated small animal monitoring devices make a reliable cardiac triggering and respiratory gating feasible. MRI in combination with molecular probes enables the noninvasive imaging of biological processes at a molecular level. Different kinds of iron oxide or gadolinium-based contrast agents can be used for this purpose. Compared to other molecular imaging modalities, like single photon emission computed tomography (SPECT) and positron emission tomography (PET), MRI can also provide imaging with high spatial resolution, which is of high importance for the assessment of the cardiovascular system. The sensitivity for detection of MRI contrast agents is however lower compared to sensitivity of radiation associated techniques like PET and SPECT. This chapter is divided into the following sections: (1) "Introduction," (2) "Principals of Magnetic Resonance Imaging," (3) "MRI Systems for Preclinical Imaging and Experimental Setup," and (4) "Cardiovascular Magnetic Resonance Imaging."
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Affiliation(s)
- René M Botnar
- Division of Imaging Sciences, King's College London, London, United Kingdom
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Nölte I, Gorbey S, Boll H, Figueiredo G, Groden C, Lemmer B, Brockmann MA. Maintained functionality of an implantable radiotelemetric blood pressure and heart rate sensor after magnetic resonance imaging in rats. Physiol Meas 2011; 32:1941-51. [PMID: 22047995 DOI: 10.1088/0967-3334/32/12/005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Radiotelemetric sensors for in vivo assessment of blood pressure and heart rate are widely used in animal research. MRI with implanted sensors is regarded as contraindicated as transmitter malfunction and injury of the animal may be caused. Moreover, artefacts are expected to compromise image evaluation. In vitro, the function of a radiotelemetric sensor (TA11PA-C10, Data Sciences International) after exposure to MRI up to 9.4 T was assessed. The magnetic force of the electromagnetic field on the sensor as well as radiofrequency (RF)-induced sensor heating was analysed. Finally, MRI with an implanted sensor was performed in a rat. Imaging artefacts were analysed at 3.0 and 9.4 T ex vivo and in vivo. Transmitted 24 h blood pressure and heart rate were compared before and after MRI to verify the integrity of the telemetric sensor. The function of the sensor was not altered by MRI up to 9.4 T. The maximum force exerted on the sensor was 273 ± 50 mN. RF-induced heating was ruled out. Artefacts impeded the assessment of the abdomen and thorax in a dead rat, but not of the head and neck. MRI with implanted radiotelemetric sensors is feasible in principal. The tested sensor maintains functionality up to 9.4 T. Artefacts hampered abdominal and throacic imaging in rats, while assessment of the head and neck is possible.
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Affiliation(s)
- I Nölte
- Department of Neuroradiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
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Evaluation of a continuous-rotation, high-speed scanning protocol for micro-computed tomography. J Comput Assist Tomogr 2011; 35:517-23. [PMID: 21765313 DOI: 10.1097/rct.0b013e31821c662b] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Micro-computed tomography is used frequently in preclinical in vivo research. Limiting factors are radiation dose and long scan times. The purpose of the study was to compare a standard step-and-shoot to a continuous-rotation, high-speed scanning protocol. METHODS Micro-computed tomography of a lead grid phantom and a rat femur was performed using a step-and-shoot and a continuous-rotation protocol. Detail discriminability and image quality were assessed by 3 radiologists. The signal-to-noise ratio and the modulation transfer function were calculated, and volumetric analyses of the femur were performed. The radiation dose of the scan protocols was measured using thermoluminescence dosimeters. RESULTS The 40-second continuous-rotation protocol allowed a detail discriminability comparable to the step-and-shoot protocol at significantly lower radiation doses. No marked differences in volumetric or qualitative analyses were observed. CONCLUSIONS Continuous-rotation micro-computed tomography significantly reduces scanning time and radiation dose without relevantly reducing image quality compared with a normal step-and-shoot protocol.
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Wang Q, Luan W, Goz V, Burakoff SJ, Hiotis SP. Non-invasive in vivo imaging for liver tumour progression using an orthotopic hepatocellular carcinoma model in immunocompetent mice. Liver Int 2011; 31:1200-8. [PMID: 21745281 DOI: 10.1111/j.1478-3231.2011.02523.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
BACKGROUND Maintenance of complex transgenic colonies and labour-intensive techniques pose significant challenges in work involving mouse models for hepatocellular carcinoma (HCC). Other animal models of unusual species are generally impractical for research purposes. AIMS To develop a highly reproducible orthotopic mouse model for HCC based on the murine α-foetoprotein (AFP), producing cell line Hepa1-6 and to monitor liver tumour progression via in vivo imaging, and measurement of plasma AFP. METHODS Intrahepatic tumour was induced following subcapsular implantation of 10(+6) Hepa1-6 cells into C57L/J mice. AFP production was examined in vitro and in vivo using immunoblotting. Three confirmatory non-invasive imaging modalities were applied to follow tumour progression over time including ultrasound biomicroscopy (UBM), micromagnetic resonance imaging (microMRI), and bioluminescence. RESULTS α-foetoprotein expression was confirmed both in vitro and in vivo, with increasing levels in the plasma as tumours progressed. UBM, microMRI and bioluminescence detected intrahepatic tumours to a 2 mm resolution by day 14. Sequential imaging studies demonstrated an intrahepatic pattern of disease progression with an observed median survival of 29 days. Immunosuppression of tumour-bearing mice led to a greater tumour size and decreased survival. CONCLUSIONS Intrahepatic implantation of Hepa1-6 as a mouse model for HCC is a highly reproducible in vivo system with tumour biology analogous to human disease and is regulated by the presence of an intact host immune system. Tumour progression may be monitored in vivo by UBM, microMRI and bioluminescence. Plasma AFP increases over time, allowing redundancy in non-invasive means of following tumour progression.
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Affiliation(s)
- Qin Wang
- Department of Surgery, Mount Sinai School of Medicine, New York, NY, USA
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Besheer A, Caysa H, Metz H, Mueller T, Kressler J, Mäder K. Benchtop-MRI for in vivo imaging using a macromolecular contrast agent based on hydroxyethyl starch (HES). Int J Pharm 2011; 417:196-203. [DOI: 10.1016/j.ijpharm.2010.10.051] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Revised: 10/17/2010] [Accepted: 10/19/2010] [Indexed: 10/18/2022]
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Non-invasive optical imaging of muscle pathology in mdx mice using cathepsin caged near-infrared imaging. Mol Imaging Biol 2011; 13:462-470. [PMID: 20661652 PMCID: PMC3087873 DOI: 10.1007/s11307-010-0376-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE To develop a reliable live-animal imaging method for monitoring muscle pathology in mouse models of myopathy. PROCEDURES A caged near-infrared Cathepsin B (CTSB) substrate, ProSense 680, is evaluated in the dystrophin deficient mdx mice, a genetic homologue of Duchenne muscular dystrophy via optical imaging. RESULTS We show high levels of infrared signal in dystrophic muscle relative to healthy muscle at 24 h post-injection. Imaging for CTSB presence revealed localization to inflammatory infiltrates and regenerating muscle fibers. A time series myotoxin-induced muscle injury experiment showed that CTSB activity and its mRNA levels peaked at the interface between inflammation and myoblast fusion stage of recovery. Prednisone treatment in mdx mice resulted in decreased CTSB activity and increased grip strength in forelimbs and hindlimbs. CONCLUSIONS Optical imaging of CTSB activity is an ideal method to sensitively monitor inflammation, regeneration, and response to therapy in myopathic skeletal muscle.
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Caysa H, Metz H, Mäder K, Mueller T. Application of Benchtop-magnetic resonance imaging in a nude mouse tumor model. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2011; 30:69. [PMID: 21777437 PMCID: PMC3158420 DOI: 10.1186/1756-9966-30-69] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Accepted: 07/21/2011] [Indexed: 11/29/2022]
Abstract
Background MRI plays a key role in the preclinical development of new drugs, diagnostics and their delivery systems. However, very high installation and running costs of existing superconducting MRI machines limit the spread of MRI. The new method of Benchtop-MRI (BT-MRI) has the potential to overcome this limitation due to much lower installation and almost no running costs. However, due to the low field strength and decreased magnet homogeneity it is questionable, whether BT-MRI can achieve sufficient image quality to provide useful information for preclinical in vivo studies. It was the aim of the current study to explore the potential of BT-MRI on tumor models in mice. Methods We used a prototype of an in vivo BT-MRI apparatus to visualise organs and tumors and to analyse tumor progression in nude mouse xenograft models of human testicular germ cell tumor and colon carcinoma. Results Subcutaneous xenografts were easily identified as relative hypointense areas in transaxial slices of NMR images. Monitoring of tumor progression evaluated by pixel extension analyses based on NMR images correlated with increasing tumor volume calculated by calliper measurement. Gd-BOPTA contrast agent injection resulted in a better differentiation between parts of the urinary tissues and organs due to fast elimination of the agent via kidneys. In addition, interior structuring of tumors could be observed. A strong contrast enhancement within a tumor was associated with a central necrotic/fibrotic area. Conclusions BT-MRI provides satisfactory image quality to visualize organs and tumors and to monitor tumor progression and structure in mouse models.
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Affiliation(s)
- Henrike Caysa
- Martin-Luther-University Halle-Wittenberg, Department of Pharmaceutics and Biopharmaceutics, Wolfgang-Langenbeck-Str. 4, 06114 Halle/Saale, Germany
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Chen F. Feng Chen's work on translational and clinical imaging. World J Radiol 2011; 3:120-4. [PMID: 21532873 PMCID: PMC3084436 DOI: 10.4329/wjr.v3.i4.120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 03/28/2011] [Accepted: 04/04/2011] [Indexed: 02/06/2023] Open
Abstract
Dr. Feng Chen is a chief medical doctor and the vice chairman of the Department of Radiology in Zhong Da Hospital at Southeast University, Nanjing, China and a senior researcher in the Department of Radiology at the Catholic University of Leuven, Belgium. His main areas of interest are translational imaging research including stroke, tumor angiogenesis, assessment of therapeutic response in solid tumors, and magnetic resonance contrast media. Dr. Feng Chen has published 44 scientific papers in peer-reviewed international journals. He and his colleagues have developed an imaging platform which includes animal models, animal preparations and multiparametric magnetic resonance imaging (MRI) protocols for translational animal imaging research using clinical machines. His MRI findings on rodent stroke are considered to "serve as a model for future laboratory investigations of treatment of acute stroke and unify the approaches developed for clinical studies". He and his colleagues have introduced a novel liver tumor model in rodents, in which a series of studies concerning the antitumor activity of vascular disrupting agents have been successively conducted and assessed by in vivo MRI, especially by diffusion weighted imaging as an imaging biomarker. His goal is to provide valuable references for clinical practice and to contribute to the translation of animal imaging research into patient applications.
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Willekens I, Buls N, Lahoutte T, Baeyens L, Vanhove C, Caveliers V, Deklerck R, Bossuyt A, de Mey J. Evaluation of the radiation dose in micro-CT with optimization of the scan protocol. CONTRAST MEDIA & MOLECULAR IMAGING 2011; 5:201-7. [PMID: 20665903 DOI: 10.1002/cmmi.394] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
INTRODUCTION Micro-CT provides non-invasive anatomic evaluation of small animals. Serial micro-CT measurements are, however, hampered by the severity of ionizing radiation doses cumulating over the total period of follow-up. The dose levels may be sufficient to influence experimental outcomes such as animal survival or tumor growth. AIM This study was designed to evaluate the radiation dose of micro-CT and to optimize the scanning protocol for longitudinal micro-CT scans. METHODS AND MATERIALS Normal C57Bl/6 mice were euthanized. Radiation exposure was measured using individually calibrated lithium fluoride thermoluminescent dosimeters (TLDs). Thirteen TLDs were placed in the mice at the thyroid, lungs, liver, stomach, colon, bladder and near the spleen. Micro-CT (SkyScan 1178) was performed using two digital X-ray cameras which scanned over 180 degrees at a resolution of 83 microm, a rotation step of 1.08 degrees , 50 kV, 615 microA and 121 s image acquisition time. The TLDs were removed after each scan. CTDI(100) was measured with a 100 mm ionization chamber, centrally positioned in a 2.7 cm diameter water phantom, and rotation steps were increased to reduce both scan time and radiation dose. RESULTS Internal TLD analysis demonstrated median organ dose of 5.5 +/- 0.6 mGy per mA s, confirmed by CTDI(100) with result of 6.6 mGy per mA s. A rotation step of 2.16 resulted in qualitatively accurate images. At a resolution of 83 microm the scan time is reduced to 63 s with an estimated dose of 2.9 mGy per mA s. At 166 microm resolution, the scan time is limited to 27 s, with a concordant dose of 1.2 mGy per mA s. CONCLUSIONS The radiation dose of a standard micro-CT scan is relatively high and could influence the experimental outcome. We believe that the presented adaptation of the scan protocol allows for accurate imaging without the risk of interfering with the experimental outcome of the study.
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Affiliation(s)
- Inneke Willekens
- In Vivo Cellular and Molecular Imaging, ICMI, Vrije Universiteit Brussels, Brussels, Belgium.
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Pillai DR, Heidemann RM, Kumar P, Shanbhag N, Lanz T, Dittmar MS, Sandner B, Beier CP, Weidner N, Greenlee MW, Schuierer G, Bogdahn U, Schlachetzki F. Comprehensive small animal imaging strategies on a clinical 3 T dedicated head MR-scanner; adapted methods and sequence protocols in CNS pathologies. PLoS One 2011; 6:e16091. [PMID: 21326876 PMCID: PMC3034718 DOI: 10.1371/journal.pone.0016091] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Accepted: 12/09/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Small animal models of human diseases are an indispensable aspect of pre-clinical research. Being dynamic, most pathologies demand extensive longitudinal monitoring to understand disease mechanisms, drug efficacy and side effects. These considerations often demand the concomitant development of monitoring systems with sufficient temporal and spatial resolution. METHODOLOGY AND RESULTS This study attempts to configure and optimize a clinical 3 Tesla magnetic resonance scanner to facilitate imaging of small animal central nervous system pathologies. The hardware of the scanner was complemented by a custom-built, 4-channel phased array coil system. Extensive modification of standard sequence protocols was carried out based on tissue relaxometric calculations. Proton density differences between the gray and white matter of the rodent spinal cord along with transverse relaxation due to magnetic susceptibility differences at the cortex and striatum of both rats and mice demonstrated statistically significant differences. The employed parallel imaging reconstruction algorithms had distinct properties dependent on the sequence type and in the presence of the contrast agent. The attempt to morphologically phenotype a normal healthy rat brain in multiple planes delineated a number of anatomical regions, and all the clinically relevant sequels following acute cerebral ischemia could be adequately characterized. Changes in blood-brain-barrier permeability following ischemia-reperfusion were also apparent at a later time. Typical characteristics of intra-cerebral haemorrhage at acute and chronic stages were also visualized up to one month. Two models of rodent spinal cord injury were adequately characterized and closely mimicked the results of histological studies. In the employed rodent animal handling system a mouse model of glioblastoma was also studied with unequivocal results. CONCLUSIONS The implemented customizations including extensive sequence protocol modifications resulted in images of high diagnostic quality. These results prove that lack of dedicated animal scanners shouldn't discourage conventional small animal imaging studies.
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Affiliation(s)
- Deepu R. Pillai
- Department of Neurology, Regensburg University Medical Centre, Regensburg, Germany
- Department of Genetics and Neurobiology, Biozentrum, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Robin M. Heidemann
- Department of Neurophysics, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
- Siemens Healthcare Sector, Erlangen, Germany
| | - Praveen Kumar
- Department of Neurology, Regensburg University Medical Centre, Regensburg, Germany
- Department of Neurology, University Medical Centre, RWTH Aachen, Aachen, Germany
| | - Nagesh Shanbhag
- Department of Neurology, Regensburg University Medical Centre, Regensburg, Germany
| | - Titus Lanz
- RAPID Biomedical GmbH, Würzburg-Rimpar, Germany
| | - Michael S. Dittmar
- Department of Anaesthesiology, Regensburg University Medical Centre, Regensburg, Germany
| | - Beatrice Sandner
- Department of Neurology, Regensburg University Medical Centre, Regensburg, Germany
| | - Christoph P. Beier
- Department of Neurology, Regensburg University Medical Centre, Regensburg, Germany
- Department of Neurology, University Medical Centre, RWTH Aachen, Aachen, Germany
| | - Norbert Weidner
- Department of Neurology, Regensburg University Medical Centre, Regensburg, Germany
- Institute for Paraplegia, University of Heidelberg, Heidelberg, Germany
| | - Mark W. Greenlee
- Institute for Experimental Psychology, University of Regensburg, Regensburg, Germany
| | - Gerhard Schuierer
- Center for Neuroradiology, Regensburg University Medical Centre and Bezirksklinikum Regensburg, Regensburg, Germany
| | - Ulrich Bogdahn
- Department of Neurology, Regensburg University Medical Centre, Regensburg, Germany
| | - Felix Schlachetzki
- Department of Neurology, Regensburg University Medical Centre, Regensburg, Germany
- * E-mail:
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MITSUDA M, YAMAGUCHI M, FURUTA T, NABETANI A, HIRAYAMA A, NOZAKI A, NIITSU M, FUJII H. Multiple-animal MR Imaging using a 3T Clinical Scanner and Multi-channel Coil for Volumetric Analysis in a Mouse Tumor Model. Magn Reson Med Sci 2011; 10:229-37. [DOI: 10.2463/mrms.10.229] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Cancer models-multiparametric applications of clinical MRI in rodent hepatic tumor model. Methods Mol Biol 2011; 771:489-507. [PMID: 21874495 DOI: 10.1007/978-1-61779-219-9_26] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Small animal imaging has been a major player in an increasing amount of oncological experiments wherein magnetic resonance imaging (MRI) has become a favorite choice of measures for in vivo small animal imaging due to its advantages of excellent resolution and innocuousness. Based on a clinical MRI scanner, we propose a protocol of multiparametric MRI for noninvasive characterization and therapeutic evaluation of a rat model with implanted liver tumors. This protocol contains six sequences, namely, T (1)-weighted image (T1WI), T (2)-weighted image (T2WI), diffusion-weighed imaging (DWI), T (1)-weighted dynamic contrast-enhanced MRI (DCE-MRI), T (2)-weighted dynamic susceptibility contrast-enhanced MRI (DSC-MRI), and contrast-enhanced T1WI (CE-T1WI), for acquiring anatomic, diffusion, and perfusion information of tumor models. In this chapter, the details about this complete MRI protocol and the rodent liver tumor model are described in order to facilitate the readers to perform their own translational animal imaging research.
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Sandhu GS, Solorio L, Broome AM, Salem N, Kolthammer J, Shah T, Flask C, Duerk JL. Whole animal imaging. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2010; 2:398-421. [PMID: 20836038 DOI: 10.1002/wsbm.71] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Translational research plays a vital role in understanding the underlying pathophysiology of human diseases, and hence development of new diagnostic and therapeutic options for their management. After creating an animal disease model, pathophysiologic changes and effects of a therapeutic intervention on them are often evaluated on the animals using immunohistologic or imaging techniques. In contrast to the immunohistologic techniques, the imaging techniques are noninvasive and hence can be used to investigate the whole animal, oftentimes in a single exam which provides opportunities to perform longitudinal studies and dynamic imaging of the same subject, and hence minimizes the experimental variability, requirement for the number of animals, and the time to perform a given experiment. Whole animal imaging can be performed by a number of techniques including x-ray computed tomography, magnetic resonance imaging, ultrasound imaging, positron emission tomography, single photon emission computed tomography, fluorescence imaging, and bioluminescence imaging, among others. Individual imaging techniques provide different kinds of information regarding the structure, metabolism, and physiology of the animal. Each technique has its own strengths and weaknesses, and none serves every purpose of image acquisition from all regions of an animal. In this review, a broad overview of basic principles, available contrast mechanisms, applications, challenges, and future prospects of many imaging techniques employed for whole animal imaging is provided. Our main goal is to briefly describe the current state of art to researchers and advanced students with a strong background in the field of animal research.
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Affiliation(s)
- Gurpreet Singh Sandhu
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Luis Solorio
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Ann-Marie Broome
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Nicolas Salem
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Jeff Kolthammer
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Tejas Shah
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Chris Flask
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Jeffrey L Duerk
- Department of Biomedical Engineering, Case Center of Imaging Research, Case Western Reserve University, Cleveland, OH 44106, USA
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Cardiovascular remodeling during arteriovenous fistula maturation in a rodent uremia model. J Vasc Access 2010; 12:215-23. [PMID: 21104672 DOI: 10.5301/jva.2010.6066] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2010] [Indexed: 11/20/2022] Open
Abstract
PURPOSE The aim of this study was to evaluate cardiovascular remodeling after arteriovenous fistula (AVF) surgery and to characterize the effect of chronic kidney disease (CKD) in a rodent femoral AVF model. METHODS Sixteen rats (8 healthy; 8 CKD) underwent femoral AVF surgery; 4 animals served as controls. AVF and cardiac morphology as well as function were assessed during the fistula maturation process (until day 84 after surgery) using magnetic resonance imaging and histopathological analyses. RESULTS Histopathological analysis revealed that a glomerular and interstitial nephropathy caused CKD. In healthy and CKD animals, AVF surgery resulted in progressive downstream vein dilation and a subsequent cardiac adaptation. This vein dilation during maturation was less in CKD rats during the early postoperative course (day 21: p=0.0475) and similar thereafter until day 84. The dilation was accompanied by an aggravation of neointimal hyperplasia (NIH) and calcification in AVFs of CKD rats. The chronic volume overload resulted in both groups in a significantly increased end-diastolic volume (healthy rats: p=0.0087; CKD rats: p=0.0333). Simultaneously, cardiac output increased 195% in healthy and 244% in uremic rats, which was caused by both a significantly increased stroke volume and heart rate. The left ventricular mass rose in AVF animals and was increased at the end of the study period, indicating a distinct cardiac hypertrophy. CONCLUSION Our rat model showed typical cardiovascular features of the AVF maturation process, which strongly resemble clinical findings in patients. Uremia caused inferior dilation in the early phase after surgery and an exacerbation of NIH. This model should help to identify the cellular and molecular mechanisms that contribute to AVF failure.
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Cardiovascular remodeling after AVF surgery in rats assessed by a clinical MRI scanner. Magn Reson Imaging 2010; 29:57-63. [PMID: 20832223 DOI: 10.1016/j.mri.2010.07.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Accepted: 07/26/2010] [Indexed: 11/24/2022]
Abstract
PURPOSE To evaluate a cardiovascular magnetic resonance imaging (MRI) technique which allows the longitudinal analysis of cardiovascular remodeling in a rodent femoral arteriovenous fistula (AVF) model by means of a clinical scanner. MATERIALS AND METHODS Eight rats underwent femoral AVF surgery and four rats served as controls. Vascular and cardiac morphology as well as cardiac function was assessed from Week 3 to 12 using contrast-enhanced, time-resolved magnetic resonance angiography (MRA) and cardiac MRI (cine gradient-echo sequence) at 3 T in one imaging session. RESULTS Arteriovenous surgery resulted in progressive venous dilation and a subsequent cardiac adaptation. This procedure led to downstream vasodilation of the iliac vein and inferior vena cava of 179% and 188%, respectively (3 weeks). To accommodate the increased returning blood volume, cardiac output (CO) increased significantly (P=.014; 6 weeks). This was caused by increased end-diastolic volume (EDV), stroke volume (SV) and heart rate (HR) consistent with an increased volume load. A continuous increase in heart weight peaked at 12 weeks. This increase combined with a distinct end-diastolic left ventricular dilation implied eccentric hypertrophy. CONCLUSION Small rodent MRI is feasible and clearly depicts fistula maturation and cardiac alterations. This technique proved to be a valuable tool for longitudinal in vivo monitoring in this model, which strongly resembles clinical findings in hemodialysis patients.
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Gibson CD, Carnell S, Ochner CN, Geliebter A. Neuroimaging, gut peptides and obesity: novel studies of the neurobiology of appetite. J Neuroendocrinol 2010; 22:833-45. [PMID: 20553371 PMCID: PMC3121301 DOI: 10.1111/j.1365-2826.2010.02025.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Two major biological players in the regulation of body weight are the gut and the brain. Peptides released from the gut convey information about energy needs to areas of the brain involved in homeostatic control of food intake. There is emerging evidence that human food intake is also under the control of cortical and subcortical areas related to reward and cognition. The extent to which gut hormones influence these brain areas is not fully understood. Novel methods combining the study of neural activity and hormonal signalling promise to advance our understanding of gut-brain interactions. Here, we review a growing number of animal and human studies using neuroimaging methods (functional magnetic resonance imaging, positron emission tomography) to measure brain activation in relation to nutrient loads and infusion of gut peptides. Implications for current and future pharmacological treatments for obesity are discussed.
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Affiliation(s)
- C D Gibson
- New York Obesity Research Center, St Luke's-Roosevelt Hospital Center, Columbia University College of Physicians and Surgeons, New York, NY, USA.
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Yamanami M, Yamamoto A, Iida H, Watanabe T, Kanda K, Yaku H, Nakayama Y. 3-Tesla magnetic resonance angiographic assessment of a tissue-engineered small-caliber vascular graft implanted in a rat. J Biomed Mater Res B Appl Biomater 2010; 92:156-60. [PMID: 19802838 DOI: 10.1002/jbm.b.31501] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In the development of small-caliber vascular grafts (diameter; less than 3 mm), animal implantation studies have been mostly performed by using rat abdominal aortas, and their certain patency must evaluate with sacrificing every observation periods, which is both labor-intensive and time-consuming when performing a large number of experiments. This study is the first to demonstrate the application of 3-Tesla contrast-free time-of-flight magnetic resonance angiography (TOF-MRA) in the continuous assessment of the status of a tissue-engineered vascular graft in rat. As a model graft, a single connective tubular tissue (diameter; 1.5 mm), prepared by embedding the silicone rod (diameter; 1.5 mm) into a subcutaneous pouch of a rat for 2 weeks an in vivo tissue-engineering, was used. The graft was implanted in the abdominal aorta (diameter; 1.3 mm) of the rat by end-to-end anastomosis. Repeated TOF-MRA imaging of the graft obtained over a 3-month follow-up period after implantation made it possible to evaluate the patency of the graft, both simply and noninvasively. It also permitted visualization of the connected abdominal aorta and renal and common iliac arteries having smaller caliber (diameter; less than 1 mm). In addition, the degree of the stenosis or aneurysm could also be detected. 3-Tesla MRA allowed the simplified and noninvasive assessment of the status on the vascular graft, including the formation of a stenosis or aneurysm, in the same rat at different times, which will be contributing to enhance the development of tissue-engineered vascular grafts even with small caliber.
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Affiliation(s)
- Masashi Yamanami
- Department of Bioengineering, Advanced Biomedical Engineering Center, National Cardiovascular Center Research Institute, Osaka, Japan
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Bertrand JB, Langlois JB, Bégou M, Volle J, Brun P, d'Amato T, Saoud M, Suaud-Chagny MF. Longitudinal MRI monitoring of brain damage in the neonatal ventral hippocampal lesion rat model of schizophrenia. Hippocampus 2010; 20:264-78. [PMID: 19452521 DOI: 10.1002/hipo.20628] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Rat with excitotoxic neonatal ventral hippocampal lesions (NVHL rats) is considered as a heuristic neurodevelopmental model for studying schizophrenia. Extensive study of this model is limited by the lack of clear validity criteria of such lesions and because ascertaining of the lesions is realized postmortem with histological examination after completing experiments. Here, in a first experiment, by assessing the locomotor response to amphetamine in adult NVHL rats, we further specify that the lesions must be bilateral and confined to the ventral hippocampus to obtain the validated behavioral phenotype. We then show a longitudinal magnetic resonance imaging (MRI) protocol suitable for the detection of brain structural changes in NVHL rats. The T(2)-weighted images acquired in adult NVHL rats reveal the same structural changes as those appraised with histological protocol. Moreover, we demonstrate that the lesion status in adulthood can be accurately predicted from the T(2)-weighted images acquired in the juvenile period. As technical advantages, our MRI protocol makes possible to select animals according to lesion criteria as soon as in the juvenile period before long-lasting experiments and gives access in vivo to a quantitative parameter indicative of the lesion extent. Finally, we show that the lesion size increases only slightly between juvenile and adult periods. These latter results are discussed in the context of the specific postpubertal emergence of the behavioral deficits in NVHL rats.
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Makowski MR, Wiethoff AJ, Jansen CHP, Botnar RM. Cardiovascular MRI in small animals. Expert Rev Cardiovasc Ther 2010; 8:35-47. [PMID: 20014933 DOI: 10.1586/erc.09.126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Imaging studies of cardiovascular disease in small rodents have become a prerequisite in preclinical cardiovascular research. Transgenic and gene-knockout models of cardiovascular diseases enables the investigation of the influence of single genes or groups of genes on disease pathogenesis. In addition, experimental and genetically altered models provide valuable in vivo platforms to investigate the efficacy of novel drugs and contrast agents. Owing to the excellent soft tissue contrast, high spatial and temporal resolution, as well as the tomographic nature of MRI, anatomy and function can be assessed with unique accuracy and reproducibility. Furthermore, using novel targeted MRI contrast agents, molecular changes associated with cardiovascular disease can be investigated in the same imaging session. This review focuses on recent advances in hardware, imaging sequences and probe design.
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Affiliation(s)
- Marcus R Makowski
- Division of Imaging Sciences, King's College London, 4th Floor, Lambeth Wing, St Thomas' Hospital, London SE1 7EH, UK.
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Schambach SJ, Bag S, Steil V, Isaza C, Schilling L, Groden C, Brockmann MA. Ultrafast High-Resolution In Vivo Volume-CTA of Mice Cerebral Vessels. Stroke 2009; 40:1444-50. [DOI: 10.1161/strokeaha.108.521740] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Sebastian J. Schambach
- From the Departments of Neuroradiology (S.S., S.B., C.I., C.G., M.A.B.), Radiation Oncology (V.S.), and Neurosurgical Research (L.S.), University Hospital Mannheim, Germany
| | - Simona Bag
- From the Departments of Neuroradiology (S.S., S.B., C.I., C.G., M.A.B.), Radiation Oncology (V.S.), and Neurosurgical Research (L.S.), University Hospital Mannheim, Germany
| | - Volker Steil
- From the Departments of Neuroradiology (S.S., S.B., C.I., C.G., M.A.B.), Radiation Oncology (V.S.), and Neurosurgical Research (L.S.), University Hospital Mannheim, Germany
| | - Cristina Isaza
- From the Departments of Neuroradiology (S.S., S.B., C.I., C.G., M.A.B.), Radiation Oncology (V.S.), and Neurosurgical Research (L.S.), University Hospital Mannheim, Germany
| | - Lothar Schilling
- From the Departments of Neuroradiology (S.S., S.B., C.I., C.G., M.A.B.), Radiation Oncology (V.S.), and Neurosurgical Research (L.S.), University Hospital Mannheim, Germany
| | - Christoph Groden
- From the Departments of Neuroradiology (S.S., S.B., C.I., C.G., M.A.B.), Radiation Oncology (V.S.), and Neurosurgical Research (L.S.), University Hospital Mannheim, Germany
| | - Marc A. Brockmann
- From the Departments of Neuroradiology (S.S., S.B., C.I., C.G., M.A.B.), Radiation Oncology (V.S.), and Neurosurgical Research (L.S.), University Hospital Mannheim, Germany
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Use of a clinical MRI scanner for preclinical research on rats. Radiol Phys Technol 2009; 2:13-21. [DOI: 10.1007/s12194-008-0038-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Revised: 08/22/2008] [Accepted: 08/27/2008] [Indexed: 10/21/2022]
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