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Coppola A, Zorzetto G, Piacentino F, Bettoni V, Pastore I, Marra P, Perani L, Esposito A, De Cobelli F, Carcano G, Fontana F, Fiorina P, Venturini M. Imaging in experimental models of diabetes. Acta Diabetol 2022; 59:147-161. [PMID: 34779949 DOI: 10.1007/s00592-021-01826-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/30/2021] [Indexed: 12/01/2022]
Abstract
Translational medicine, experimental medicine and experimental animal models, in particular mice and rats, represent a multidisciplinary field that has made it possible to achieve, in the last decades, important scientific progress. In this review, we have summarized the most frequently used imaging animal models, such as ultrasound (US), micro-CT, MRI and the optical imaging methods, and their main implications in diagnostic and therapeutic fields, with a particular focus on diabetes mellitus, a multifactorial disease extremely widespread among the general population.
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Affiliation(s)
- Andrea Coppola
- Diagnostic and Interventional Radiology Unit, ASST Settelaghi, Varese, Italy.
| | | | - Filippo Piacentino
- Diagnostic and Interventional Radiology Unit, ASST Settelaghi, Varese, Italy
- Insubria University, Varese, Italy
| | - Valeria Bettoni
- Diagnostic and Interventional Radiology Unit, ASST Settelaghi, Varese, Italy
| | - Ida Pastore
- Division of Endocrinology, ASST Fatebenefratelli-Sacco, Milan, Italy
| | - Paolo Marra
- Department of Diagnostic Radiology, Giovanni XXIII Hospital, Milano-Bicocca University, Bergamo, Italy
| | - Laura Perani
- Experimental Imaging Center, San Raffaele Scientific Institute, Milan, Italy
| | - Antonio Esposito
- Experimental Imaging Center, San Raffaele Scientific Institute, Milan, Italy
- Radiology Unit, San Raffaele Scientific Institute, San Raffaele Vita-Salute University, Milan, Italy
| | - Francesco De Cobelli
- Radiology Unit, San Raffaele Scientific Institute, San Raffaele Vita-Salute University, Milan, Italy
| | - Giulio Carcano
- Insubria University, Varese, Italy
- General, Emergency, and Transplant Surgery Unit, ASST Settelaghi, Varese, Italy
| | - Federico Fontana
- Diagnostic and Interventional Radiology Unit, ASST Settelaghi, Varese, Italy
- Insubria University, Varese, Italy
| | - Paolo Fiorina
- International Center for T1D, Centro di Ricerca Pediatrica Romeo ed Enrica Invernizzi, Dipartimento di Scienze Biomediche e Cliniche "L. Sacco", Università di Milano, Milan, Italy
- Nephrology Division, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Endocrinology Division, ASST Fatebenefratelli Sacco, Milan, Italy
| | - Massimo Venturini
- Diagnostic and Interventional Radiology Unit, ASST Settelaghi, Varese, Italy
- Insubria University, Varese, Italy
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Can Dynamic Contrast-Enhanced CT Quantify Perfusion in a Stimulated Muscle of Limited Size? A Rat Model. Clin Orthop Relat Res 2020; 478:179-188. [PMID: 31794491 PMCID: PMC7000042 DOI: 10.1097/corr.0000000000001045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Muscle injury may result in damage to the vasculature, rendering it unable to meet the metabolic demands of muscle regeneration and healing. Therefore, therapies frequently aim to maintain, restore, or improve blood supply to the injured muscle. Although there are several options to assess the vascular outcomes of these therapies, few are capable of spatially assessing perfusion in large volumes of tissue. QUESTIONS/PURPOSES Can dynamic contrast-enhanced CT (DCE-CT) imaging acquired with a clinical CT scanner be used in a rat model to quantify perfusion in the anterior tibialis muscle at spatially relevant volumes, as assessed by (1) the blood flow rate and tissue blood volume in the muscle after three levels of muscle stimulation (low, medium, and maximum) relative to baseline as determined by the non-stimulated contralateral leg; and (2) how do these measurements compare with those obtained by the more standard approach of microsphere perfusion? METHODS The right anterior tibialis muscles of adult male Sprague Dawley rats were randomized to low- (n = 10), medium- (n = 6), or maximum- (n = 3) level (duty cycles of 2.5%, 5.0%, and 20%, respectively) nerve electrode coupled muscle stimulation directly followed by DCE-CT imaging. Tissue blood flow and blood volume maps were created using commercial software and volumetrically measured using NIH software. Although differences in blood flow were detectable across the studied levels of muscle stimulation, a review of the evidence suggested the absolute blood flow quantified was underestimated. Therefore, at a later date, a separate set of adult male Sprague Dawley rats were randomized for microsphere perfusion (n = 7) to define blood flow in the animal model with an accepted standard. With this technique, intra-arterial particles sized to freely flow in blood but large enough to lodge in tissue capillaries were injected. Simultaneously, blood sampling at a fixed flow rate was simultaneously performed to provide a fixed blood flow rate sample. The tissues of interest were then explanted and assessed for the total number of particles per tissue volume. Tissue blood flow rate was then calculated based on the particle count ratio within the reference sample. Note that a tissue's blood volume cannot be calculated with this method. Comparison analysis to the non-stimulated baseline leg was performed using two-tailed paired student t-test. An ANOVA was used to compare difference between stimulation groups. RESULTS DCE-CT measured (mean ± SD) increasing tissue blood flow differences in stimulated anterior tibialis muscle at 2.5% duty cycle (32 ± 5 cc/100 cc/min), 5.0% duty cycle (46 ± 13 cc/100 cc/min), and 20% duty cycle (73 ± 3 cc/100 cc/min) compared with the paired contralateral non-stimulated anterior tibialis muscle (10 ± 2 cc/100 cc/min, mean difference 21 cc/100 cc/min [95% CI 17.08 to 25.69]; 9 ± 1 cc/100 cc/min, mean difference 37 cc/100 cc/min [95% CI 23.06 to 50.11]; and 11 ± 2 cc/100 cc/min, mean difference 62 cc/100 cc/min [95% CI 53.67 to 70.03]; all p < 0.001). Similarly, DCE-CT showed increasing differences in tissue blood volumes within the stimulated anterior tibialis muscle at 2.5% duty cycle (23.2 ± 4.2 cc/100 cc), 5.0% duty cycle (39.2 ± 7.2 cc/100 cc), and 20% duty cycle (52.5 ± 13.1 cc/100 cc) compared with the paired contralateral non-stimulated anterior tibialis muscle (3.4 ± 0.7 cc/100 cc, mean difference 19.8 cc/100 cc [95% CI 16.46 to 23.20]; p < 0.001; 3.5 ± 0.4 cc/100 cc, mean difference 35.7 cc/100 cc [95% CI 28.44 to 43.00]; p < 0.001; and 4.2 ± 1.3 cc/100 cc, mean difference 48.3 cc/100 cc [95% CI 17.86 to 78.77]; p = 0.010). Microsphere perfusion measurements also showed an increasing difference in tissue blood flow in the stimulated anterior tibialis muscle at 2.5% duty cycle (62 ± 43 cc/100 cc/min), 5.0% duty cycle (89 ± 52 cc/100 cc/min), and 20% duty cycle (313 ± 269 cc/100 cc/min) compared with the paired contralateral non-stimulated anterior tibialis muscle (8 ± 4 cc/100 cc/min, mean difference 55 cc/100 cc/min [95% CI 15.49 to 94.24]; p = 0.007; 9 ± 9 cc/100 cc/min, mean difference 79 cc/100 cc/min [95% CI 33.83 to 125.09]; p = 0.003; and 18 ± 18 cc/100 cc/min, mean difference 295 cc/100 cc/min [95% CI 8.45 to 580.87]; p = 0.023). Qualitative comparison between the methods suggests that DCE-CT values underestimate tissue blood flow with a post-hoc ANOVA showing DCE-CT blood flow values within the 2.5% duty cycle group (32 ± 5 cc/100 cc/min) to be less than the microsphere perfusion value (62 ± 43 cc/100 cc/min) with a mean difference of 31 cc/100 cc/min (95% CI 2.46 to 60.23; p = 0.035). CONCLUSIONS DCE-CT using a clinical scanner is a feasible modality to measure incremental changes of blood flow and tissue blood volume within a spatially challenged small animal model. Care should be taken in studies where true blood flow values are needed, as this particular small-volume muscle model suggests true blood flow is underestimated using the specific adaptions of DCE-CT acquisition and image processing chosen. CLINICAL RELEVANCE CT perfusion is a clinically available modality allowing for translation of science from bench to bedside. Adapting the modality to fit small animal models that are relevant to muscle healing may hasten time to clinical utility.
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Liu HS, Chiang SW, Chung HW, Tsai PH, Hsu FT, Cho NY, Wang CY, Chou MC, Chen CY. Histogram analysis of T2*-based pharmacokinetic imaging in cerebral glioma grading. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2018; 155:19-27. [PMID: 29512499 DOI: 10.1016/j.cmpb.2017.11.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 10/09/2017] [Accepted: 11/14/2017] [Indexed: 06/08/2023]
Abstract
BACKGROUND AND OBJECTIVE To investigate the feasibility of histogram analysis of the T2*-based permeability parameter volume transfer constant (Ktrans) for glioma grading and to explore the diagnostic performance of the histogram analysis of Ktrans and blood plasma volume (vp). METHODS We recruited 31 and 11 patients with high- and low-grade gliomas, respectively. The histogram parameters of Ktrans and vp, derived from the first-pass pharmacokinetic modeling based on the T2* dynamic susceptibility-weighted contrast-enhanced perfusion-weighted magnetic resonance imaging (T2* DSC-PW-MRI) from the entire tumor volume, were evaluated for differentiating glioma grades. RESULTS Histogram parameters of Ktrans and vp showed significant differences between high- and low-grade gliomas and exhibited significant correlations with tumor grades. The mean Ktrans derived from the T2* DSC-PW-MRI had the highest sensitivity and specificity for differentiating high-grade gliomas from low-grade gliomas compared with other histogram parameters of Ktrans and vp. CONCLUSIONS Histogram analysis of T2*-based pharmacokinetic imaging is useful for cerebral glioma grading. The histogram parameters of the entire tumor Ktrans measurement can provide increased accuracy with additional information regarding microvascular permeability changes for identifying high-grade brain tumors.
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Affiliation(s)
- Hua-Shan Liu
- School of Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan; International Ph.D. Program in Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, Taipei, Taiwan; Research Center of Translational Imaging, College of Medicine, Taipei Medical University, Taipei, Taiwan; Radiogenomic Research Center, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan
| | - Shih-Wei Chiang
- Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan; Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Hsiao-Wen Chung
- Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan; Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan
| | - Ping-Huei Tsai
- Research Center of Translational Imaging, College of Medicine, Taipei Medical University, Taipei, Taiwan; Radiogenomic Research Center, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan; Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Medical Imaging, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan; Department of Medical Research, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan
| | - Fei-Ting Hsu
- Research Center of Translational Imaging, College of Medicine, Taipei Medical University, Taipei, Taiwan; Radiogenomic Research Center, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan; Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Medical Imaging, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan
| | - Nai-Yu Cho
- Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Chao-Ying Wang
- Department and Graduate Institute of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | - Ming-Chung Chou
- Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Healthcare Administration and Medical Informatics, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Cheng-Yu Chen
- Research Center of Translational Imaging, College of Medicine, Taipei Medical University, Taipei, Taiwan; Radiogenomic Research Center, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan; Department of Radiology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Medical Imaging, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan; Department of Medical Research, Taipei Medical University Hospital, Taipei Medical University, Taipei, Taiwan.
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Karegowda LH, Kadavigere R, Shenoy PM, Paruthikunnan SM. Efficacy of Perfusion Computed Tomography (PCT) in Differentiating High-Grade Gliomas from Low Grade Gliomas, Lymphomas, Metastases and Abscess. J Clin Diagn Res 2017; 11:TC28-TC33. [PMID: 28658875 DOI: 10.7860/jcdr/2017/24835.9917] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 02/01/2017] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Tumoural angioneogenesis and its quantification are important in predicting the tumour grade and in the management with respect to the treatment available and to assess the response to treatment and the prognosis. It also plays major role in the growth and spread of tumours. Hence, a need arises for non-invasive in vivo methods to assess tumour angioneogenesis and tumour grade at the time of presentation and for monitoring the response during treatment and follow up. In this regard Perfusion Computed Tomography (PCT) can be easily added into routine CT studies to obtain such information on lesion physiology along with its morphology. AIM Prospective evaluation of the efficacy of PCT in differentiating high grade gliomas from low grade glioma lymphomas, metastases and abscess. MATERIALS AND METHODS Perfusion CT was performed in 68 patients (17 high-grade gliomas, 10 low-grade gliomas, 7 lymphomas, 27 metastases and 7 abscess). Perfusion parameters which include Cerebral Blood Volume (CBV), Cerebral Blood Flow (CBF), Mean Transit Time (MTT) and Time To Peak (TTP) were derived both from the lesion and the normal parenchyma and were Normalized (n) by obtaining the ratio. Statistical analysis for high grade versus low-grade gliomas, high grade gliomas versus lymphomas, metastases and abscess was performed. RESULTS Difference in the mean nCBV and nCBF in high grade gliomas were statistically significant from low grade gliomas with cut off of > 3.07 for nCBV and > 2.08 for nCBF yielding good sensitivity and specificity. Difference in the mean nCBV and nMTT in the lymphomas were statistically significant from high grade gliomas (p<0.05) with cut off of <3.40 for nCBV and >1.83 for nMTT yielding good sensitivity and specificity. Difference in the mean nCBV and nMTT in the metastases were statistically significant from high grade gliomas (p<0.05) with cut off of >4.95 for nCBV and >1.88 for nMTT yielding a fair sensitivity and specificity. No statistical significant difference seen among the parameters in differentiating high grade gliomas and abscess. CONCLUSION Cerebral PCT greatly adds to the diagnostic accuracy when the diagnosis of a common intra-axial lesion based on morphological characters becomes uncertain.
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Affiliation(s)
| | - Rajagopal Kadavigere
- Professor, Department of Radiodiagnosis and Imaging, Kasturba Medical College and Hospital, Manipal, Karnataka, India
| | - Poonam Mohan Shenoy
- Speciality Doctor, Department of Radiology, Wrexham Maelor Hospital, Betsi Cadwaladr University Health Board, Croesnewydd Road, LL13 7TD, Wrexham, United Kingdom
| | - Samir Mustaffa Paruthikunnan
- Assistant Professor, Department of Radiodiagnosis and Imaging, Kasturba Medical College and Hospital, Manipal, Karnataka, India
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Lee S, Barbe MF, Scalia R, Goldfinger LE. Three-dimensional reconstruction of neovasculature in solid tumors and basement membrane matrix using ex vivo X-ray microcomputed tomography. Microcirculation 2015; 21:159-70. [PMID: 25279426 DOI: 10.1111/micc.12102] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 10/22/2013] [Indexed: 01/13/2023]
Abstract
OBJECTIVE To create accurate, high-resolution 3D reconstructions of neovasculature structures in xenografted tumors and Matrigel plugs for quantitative analyses in angiogenesis studies in animal models. METHODS The competent neovasculature within xenografted solid tumors or Matrigel plugs in mice was perfused with Microfil, a radioopaque, hydrophilic polymerizing contrast agent, by systemic perfusion of the blood circulation via the heart. The perfused tumors and plugs were resected and scanned by X-ray micro-CT to generate stacks of 2D images showing the radioopaque material. A nonbiased, precise postprocessing scheme was employed to eliminate background X-ray absorbance from the extravascular tissue. The revised binary image stacks were compiled to reveal the Microfil-casted neovasculature as 3D reconstructions. Vascular structural parameters were calculated from the refined 3D reconstructions using the scanner software. RESULTS Clarified 3D reconstructions were sufficiently precise to allow measurements of vascular architecture to a diametric limit of resolution of 3 μm in tumors and plugs. CONCLUSIONS Ex vivo micro-CT can be used for 3D reconstruction and quantitative analysis of neovasculature including microcirculation in solid tumors and Matrigel plugs. This method can be generally applied for reconstructing and measuring vascular structures in three dimensions.
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Affiliation(s)
- Seunghyung Lee
- Department of Anatomy & Cell Biology, Temple University School of Medicine, Philadelphia, Pennsylvania, USA; The Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania, USA
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Dynamic contrast-enhanced micro-computed tomography correlates with 3-dimensional fluorescence ultramicroscopy in antiangiogenic therapy of breast cancer xenografts. Invest Radiol 2015; 49:445-56. [PMID: 24598441 DOI: 10.1097/rli.0000000000000038] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVES Dynamic contrast-enhanced (DCE) micro-computed tomography (micro-CT) has emerged as a valuable imaging tool to noninvasively obtain quantitative physiological biomarkers of drug effect in preclinical studies of antiangiogenic compounds. In this study, we explored the ability of DCE micro-CT to assess the antiangiogenic treatment response in breast cancer xenografts and correlated the results to the structural vessel response obtained from 3-dimensional (3D) fluorescence ultramicroscopy (UM). MATERIAL AND METHODS Two groups of tumor-bearing mice (KPL-4) underwent DCE micro-CT imaging using a fast preclinical dual-source micro-CT system (TomoScope Synergy Twin, CT Imaging GmbH, Erlangen, Germany). Mice were treated with either a monoclonal antibody against the vascular endothelial growth factor or an unspecific control antibody. Changes in vascular physiology were assessed measuring the mean value of the relative blood volume (rBV) and the permeability-surface area product (PS) in different tumor regions of interest (tumor center, tumor periphery, and total tumor tissue). Parametric maps of rBV were calculated of the tumor volume to assess the intratumoral vascular heterogeneity. Isotropic 3D UM vessel scans were performed from excised tumor tissue, and automated 3D segmentation algorithms were used to determine the microvessel density (MVD), relative vessel volume, and vessel diameters. In addition, the accumulation of coinjected fluorescence-labeled trastuzumab was quantified in the UM tissue scans to obtain an indirect measure of vessel permeability. Results of the DCE micro-CT were compared with corresponding results obtained by ex vivo UM. For validation, DCE micro-CT and UM parameters were compared with conventional histology and tumor volume. RESULTS Examination of the parametric rBV maps revealed significantly different patterns of intratumoral blood supply between treated and control tumors. Whereas control tumors showed a characteristic vascular rim pattern with considerably elevated rBV values in the tumor periphery, treated tumors showed a widely homogeneous blood supply. Compared with UM, the physiological rBV maps showed excellent agreement with the spatial morphology of the intratumoral vascular architecture. Regional assessment of mean physiological values exhibited a significant decrease in rBV (P < 0.01) and PS (P < 0.05) in the tumor periphery after anti-vascular endothelial growth factor treatment. Structural validation with UM showed a significant reduction in reduction of relative vessel volume (rVV) (P < 0.01) and MVD (P < 0.01) in the corresponding tumor region. The reduction in rBV correlated well with the rVV (R = 0.73 for single values and R = 0.95 for mean values). Spatial maps of antibody penetration showed a significantly reduced antibody accumulation (P < 0.01) in the tumor tissue after treatment and agreed well with the physiological change of PS. Examination of vessel diameters revealed a size-dependent antiangiogenic treatment effect, which showed a significant reduction in MVD (P < 0.001) for vessels with diameters smaller than 25 μm. No treatment effect was observed by tumor volume. CONCLUSIONS Noninvasive DCE micro-CT provides valuable physiological information of antiangiogenic drug effect in the intact animal and correlates with ex vivo structural analysis of 3D UM. The combined use of DCE micro-CT with UM constitutes a complementary imaging toolset that can help to enhance our understanding of antiangiogenic drug mechanisms of action in preclinical drug research.
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Kim SH, Kamaya A, Willmann JK. CT perfusion of the liver: principles and applications in oncology. Radiology 2014; 272:322-44. [PMID: 25058132 DOI: 10.1148/radiol.14130091] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
With the introduction of molecularly targeted chemotherapeutics, there is an increasing need for defining new response criteria for therapeutic success because use of morphologic imaging alone may not fully assess tumor response. Computed tomographic (CT) perfusion imaging of the liver provides functional information about the microcirculation of normal parenchyma and focal liver lesions and is a promising technique for assessing the efficacy of various anticancer treatments. CT perfusion also shows promising results for diagnosing primary or metastatic tumors, for predicting early response to anticancer treatments, and for monitoring tumor recurrence after therapy. Many of the limitations of early CT perfusion studies performed in the liver, such as limited coverage, motion artifacts, and high radiation dose of CT, are being addressed by recent technical advances. These include a wide area detector with or without volumetric spiral or shuttle modes, motion correction algorithms, and new CT reconstruction technologies such as iterative algorithms. Although several issues related to perfusion imaging-such as paucity of large multicenter trials, limited accessibility of perfusion software, and lack of standardization in methods-remain unsolved, CT perfusion has now reached technical maturity, allowing for its use in assessing tumor vascularity in larger-scale prospective clinical trials. In this review, basic principles, current acquisition protocols, and pharmacokinetic models used for CT perfusion imaging of the liver are described. Various oncologic applications of CT perfusion of the liver are discussed and current challenges, as well as possible solutions, for CT perfusion are presented.
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Affiliation(s)
- Se Hyung Kim
- From the Department of Radiology, Molecular Imaging Program at Stanford, School of Medicine, Stanford University, 300 Pasteur Dr, Room H1307, Stanford, CA 94305-5621 (S.H.K., A.K., J.K.W.); and Department of Radiology and Institute of Radiation Medicine, Seoul National University Hospital, Seoul, Korea (S.H.K.)
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Clark DP, Badea CT. Micro-CT of rodents: state-of-the-art and future perspectives. Phys Med 2014; 30:619-34. [PMID: 24974176 PMCID: PMC4138257 DOI: 10.1016/j.ejmp.2014.05.011] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 05/15/2014] [Accepted: 05/28/2014] [Indexed: 02/06/2023] Open
Abstract
Micron-scale computed tomography (micro-CT) is an essential tool for phenotyping and for elucidating diseases and their therapies. This work is focused on preclinical micro-CT imaging, reviewing relevant principles, technologies, and applications. Commonly, micro-CT provides high-resolution anatomic information, either on its own or in conjunction with lower-resolution functional imaging modalities such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT). More recently, however, advanced applications of micro-CT produce functional information by translating clinical applications to model systems (e.g., measuring cardiac functional metrics) and by pioneering new ones (e.g. measuring tumor vascular permeability with nanoparticle contrast agents). The primary limitations of micro-CT imaging are the associated radiation dose and relatively poor soft tissue contrast. We review several image reconstruction strategies based on iterative, statistical, and gradient sparsity regularization, demonstrating that high image quality is achievable with low radiation dose given ever more powerful computational resources. We also review two contrast mechanisms under intense development. The first is spectral contrast for quantitative material discrimination in combination with passive or actively targeted nanoparticle contrast agents. The second is phase contrast which measures refraction in biological tissues for improved contrast and potentially reduced radiation dose relative to standard absorption imaging. These technological advancements promise to develop micro-CT into a commonplace, functional and even molecular imaging modality.
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Affiliation(s)
- D P Clark
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Box 3302, Durham, NC 27710, USA
| | - C T Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Box 3302, Durham, NC 27710, USA.
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Jain R. Measurements of tumor vascular leakiness using DCE in brain tumors: clinical applications. NMR IN BIOMEDICINE 2013; 26:1042-1049. [PMID: 23832526 DOI: 10.1002/nbm.2994] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 06/05/2013] [Accepted: 06/06/2013] [Indexed: 06/02/2023]
Abstract
Various imaging techniques have been employed to evaluate blood-brain-barrier leakiness in brain tumors, as higher tumor vascular leakiness is known to be associated with higher grade and malignant potential of the tumor, and hence can help provide additional diagnostic and prognostic information. These imaging techniques range from routine post-contrast T1 -weighted images that highlight degree of contrast enhancement to absolute measurement of quantitative metrics of vascular leakiness employing complex pharmacokinetic modeling. The purpose of this article is to discuss the clinical applications of available imaging techniques, and in particular dynamic contrast-enhanced T1 -weighted MR imaging (DCE-MRI), to evaluate tumor vascular leakiness.
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Affiliation(s)
- Rajan Jain
- Department of Radiology, Division of Neuroradiology, Henry Ford Health System, Detroit, MI 48202, USA.
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Lee YJ, Ahn KJ, Kim BS, Yoo WJ. Role of perfusion CT in differentiating between various cerebral masses using normalized permeability surface area product and cerebral blood volume. Clin Imaging 2012; 36:680-7. [PMID: 23153995 DOI: 10.1016/j.clinimag.2012.01.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 01/24/2012] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The objective was to assess usefulness of a combined analysis using the perfusion computed tomography parameters permeability surface area product (PS) and cerebral blood volume (CBV) in the differential grouping of various cerebral masses. METHODS Thirty patients who had a cerebral mass, confirmed by pathologic verification, were included. We classified PS and CBV results for various cerebral masses by visual as well as semiquantitative assessment. To verify statistically significant differences between the groups, one-way analysis of variance was performed. RESULTS Patients were categorized into five groups with statistically significant differences (P<.01). CONCLUSIONS PS and CBV were useful in the differential diagnosis of cerebral masses.
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Affiliation(s)
- Youn-Joo Lee
- Department of Radiology, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, South Korea
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Stecco A, Fabbiano F, Amatuzzo P, Cignini E, Brambilla M, Masini L, Krengli M, Carriero A. Perfusion computed tomography assessments of peri-enhancing brain tissue in high-grade gliomas. LA RADIOLOGIA MEDICA 2012; 118:431-43. [PMID: 22872457 DOI: 10.1007/s11547-012-0865-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 01/03/2012] [Indexed: 10/28/2022]
Abstract
PURPOSE This study was undertaken to identify tumoural infiltration of peri-enhancing brain tissue in patients with glioblastoma by means of perfusion computed tomography (PCT) parameters, cerebral blood volume (CBV) and permeability surface (PS). MATERIALS AND METHODS Eight patients with surgically treated glioblastoma who were eligible for radiotherapy and nine patients with brain metastases from lung and breast cancer underwent CT before and after injection of contrast medium. CBV and PS were calculated in the contrast-enhancing lesion area, in the area of perilesional oedema and in the normal-appearing white matter (NAWM), normalised to contralateral symmetrical areas. RESULTS No significant differences were found for normalised CBV (nCBV) and nPS in NAWM regions between metastasis and glioma. Significant differences in nPS (p<0.005) were found between the typically vasogenic oedema surrounding the metastases and signal alteration surrounding the glial neoplasm. On the contrary, no significant differences were detected in the same areas for nCBV. CONCLUSIONS PCT can analyse the histopathological substrate underlying the hypodense peritumoural halo and differentiate between vasogenic oedema and neoplastic infiltration on the basis of the PS parameter. In our study, PS was more informative than CBV. These findings can be used to integrate plans for radiation therapy and/or surgery.
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Affiliation(s)
- A Stecco
- SCDU Radiologia, AOU Maggiore della Carità, Università del Piemonte Orientale A. Avogadro, Novara, Italy.
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Antiangiogenic and radiation therapy: early effects on in vivo computed tomography perfusion parameters in human colon cancer xenografts in mice. Invest Radiol 2012; 47:25-32. [PMID: 22178893 DOI: 10.1097/rli.0b013e31823a82f6] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
OBJECTIVES To assess early treatment effects on computed tomography (CT) perfusion parameters after antiangiogenic and radiation therapy in subcutaneously implanted, human colon cancer xenografts in mice and to correlate in vivo CT perfusion parameters with ex vivo assays of tumor vascularity and hypoxia. MATERIALS AND METHODS Dynamic contrast-enhanced CT (perfusion CT, 129 mAs, 80 kV, 12 slices × 2.4 mm; 150 μL iodinated contrast agent injected at a rate of 1 mL/min intravenously) was performed in 100 subcutaneous human colon cancer xenografts on baseline day 0. Mice in group 1 (n=32) received a single dose of the antiangiogenic agent bevacizumab (10 mg/kg body weight), mice in group 2 (n=32) underwent a single radiation treatment (12 Gy), and mice in group 3 (n=32) remained untreated. On days 1, 3, 5, and 7 after treatment, 8 mice from each group underwent a second CT perfusion scan, respectively, after which tumors were excised for ex vivo analysis. Four mice were killed after baseline scanning on day 0 for ex vivo analysis. Blood flow (BF), blood volume (BV), and flow extraction product were calculated using the left ventricle as an arterial input function. Correlation of in vivo CT perfusion parameters with ex vivo microvessel density and extent of tumor hypoxia were assessed by immunofluorescence. Reproducibility of CT perfusion parameter measurements was calculated in an additional 8 tumor-bearing mice scanned twice within 5 hours with the same CT perfusion imaging protocol. RESULTS The intraclass correlation coefficients for BF, BV, and flow extraction product from repeated CT perfusion scans were 0.93 (95% confidence interval: 0.78, 0.97), 0.88 (0.66, 0.95), and 0.88 (0.56, 0.95), respectively. Changes in perfusion parameters and tumor volumes over time were different between treatments. After bevacizumab treatment, all 3 perfusion parameters significantly decreased from day 1 (P ≤ 0.006) and remained significantly decreased until day 7 (P ≤ 0.008); tumor volume increased significantly only on day 7 (P=0.04). After radiation treatment, all 3 perfusion parameters decreased significantly on day 1 (P < 0.001); BF and flow extraction product increased again on day 3 and 5, although without reaching statistically significant difference; and tumor volumes did not change significantly at all time points (P ≥ 0.3). In the control group, all 3 perfusion parameters did not change significantly, whereas tumor volume increased significantly at all the time points, compared with baseline (P ≤ 0.04). Ex vivo immunofluorescent staining showed good correlation between all 3 perfusion parameters and microvessel density (ρ=0.71, 0.66, and 0.69 for BF, BV, and flow extraction product, respectively; P < 0.001). There was a trend toward negative correlation between extent of hypoxia and all 3 perfusion parameters (ρ=-0.53, -0.47, and -0.40 for BF, BV, and flow extraction product, respectively; P ≥ 0.05). CONCLUSIONS CT perfusion allows a reproducible, noninvasive assessment of tumor vascularity in human colon cancer xenografts in mice. After antiangiogenic and radiation therapy, BF, BV, and flow extraction product significantly decrease and change faster than the tumor volume.
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Guan LM, Qi XX, Xia B, Li ZH, Zhao Y, Xu K. Early changes measured by CT perfusion imaging in tumor microcirculation following radiosurgery in rat C6 brain gliomas. J Neurosurg 2011; 114:1672-80. [DOI: 10.3171/2011.1.jns101513] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
In this paper, the authors' aim was to use CT perfusion imaging to evaluate the early changes in tumor microcirculation following radiosurgery in rat C6 brain gliomas.
Methods
C6 glioma cells were inoculated into the right caudate nucleus of 25 Wistar rats using a stereotactic procedure. Tumor-bearing rats were randomly divided into 2 groups (tumor group and treatment group). Rats in the treatment group received maximal doses of 20 Gy delivered by the X-knife unit 16 days postimplantation. Computed tomography perfusion imaging was performed in all rats 3 weeks after tumor implantation prior to death and histopathological analysis.
Results
Hypocellular regions and tumor edema were increased in the treatment group compared with the tumor group. Parameters of CT perfusion imaging including cerebral blood volume (CBV) and mean transit time (MTT) of the tumors as well as the permeability surface area (PSA) product in the tumor-brain districts were decreased in the treatment group compared with the tumor group (p < 0.05). Although microvascular density (MVD) in the periphery of the tumors in the treatment group was higher than that in the normal contralateral brain (p < 0.05), MVD of the tumors in the treatment group was less than that in the tumor group (p < 0.01). There was a positive correlation between cerebral blood flow (CBF) and MVD as well as CBV and MVD in the center and periphery of tumors in both groups (p < 0.05).
Conclusions
A decrease in the perfusion volume of rat C6 brain gliomas was observed during the acute stage following X-knife treatment, and CBF and CBV were positively correlated with MVD of rat C6 brain gliomas. Thus, CT perfusion imaging can be used to evaluate the early changes in tumor microcirculation following radiosurgery.
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Affiliation(s)
| | | | | | - Zhen-hua Li
- 3Pathology, The No. 1 Hospital of China Medical University, Shenyang, China
| | | | - Ke Xu
- 1Departments of Radiology,
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Dynamic CT perfusion imaging of intra-axial brain tumours: differentiation of high-grade gliomas from primary CNS lymphomas. Eur Radiol 2010; 20:2482-90. [PMID: 20495977 PMCID: PMC2940017 DOI: 10.1007/s00330-010-1817-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Revised: 03/17/2010] [Accepted: 03/26/2010] [Indexed: 10/30/2022]
Abstract
INTRODUCTION Perfusion computed tomography (PCT) allows to quantitatively assess haemodynamic characteristics of brain tissue. We investigated if different brain tumor types can be distinguished from each other using Patlak analysis of PCT data. METHODS PCT data from 43 patients with brain tumours were analysed with a commercial implementation of the Patlak method. Four patients had low-grade glioma (WHO II), 31 patients had glioblastoma (WHO IV) and eight patients had intracerebral lymphoma. Tumour regions of interest (ROIs) were drawn in a morphological image and automatically transferred to maps of cerebral blood flow (CBF), cerebral blood volume (CBV) and permeability (K (Trans)). Mean values were calculated, group differences were tested using Wilcoxon and Mann Whitney U-tests. RESULTS In comparison with normal parenchyma, low-grade gliomas showed no significant difference of perfusion parameters (p > 0.05) , whereas high-grade gliomas demonstrated significantly higher values (p < 0.0001 for K (Trans), p < 0.0001 for CBV and p = 0.0002 for CBF). Lymphomas displayed significantly increased mean K(Trans) values compared with unaffected cerebral parenchyma (p = 0.0078) but no elevation of CBV. High-grade gliomas show significant higher CBV values than lymphomas (p = 0.0078). DISCUSSION PCT allows to reliably classify gliomas and lymphomas based on quantitative measurements of CBV and K (Trans).
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Park CM, Goo JM, Lee HJ, Kim MA, Kim HC, Kim KG, Lee CH, Im JG. FN13762 Murine Breast Cancer: Region-by-Region Correlation of First-Pass Perfusion CT Indexes with Histologic Vascular Parameters. Radiology 2009; 251:721-30. [DOI: 10.1148/radiol.2513081215] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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16
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Tumor Blood Flow Measured by Perfusion Computed Tomography and 15O-Labeled Water Positron Emission Tomography. J Comput Assist Tomogr 2009; 33:460-5. [DOI: 10.1097/rct.0b013e318182d2e0] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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17
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Kambadakone AR, Sahani DV. Body perfusion CT: technique, clinical applications, and advances. Radiol Clin North Am 2009; 47:161-78. [PMID: 19195541 DOI: 10.1016/j.rcl.2008.11.003] [Citation(s) in RCA: 179] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Perfusion CT has made tremendous progress since its inception and is gradually broadening its applications from the research realm into routine clinical care. This has been particularly noteworthy in the oncological setting, where perfusion CT is emerging as a valuable tool in tissue characterization, risk stratification and monitoring treatment effects especially assessing early response to novel targeted therapies. Recent technological advancements in CT have paved ways to overcome the initial limitations of restricted tissue coverage and radiation dose concerns. In this article, the authors review the basic principles and technique of perfusion CT and discuss its various oncologic and non-oncological clinical applications in body imaging.
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Affiliation(s)
- Avinash R Kambadakone
- Division of Abdominal Imaging and Intervention, Department of Radiology, Massachusetts General Hospital, 55 Fruit Street, White 270, Boston, MA 02114, USA
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Wu H, Exner AA, Krupka TM, Weinberg BD, Patel R, Haaga JR. Radiofrequency ablation: post-ablation assessment using CT perfusion with pharmacological modulation in a rat subcutaneous tumor model. Acad Radiol 2009; 16:321-31. [PMID: 19201361 DOI: 10.1016/j.acra.2008.09.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Revised: 09/25/2008] [Accepted: 08/26/2008] [Indexed: 12/11/2022]
Abstract
RATIONALE AND OBJECTIVES Inflammatory reaction surrounding the ablated area is a major confounding factor in the early detection of viable tumor after radiofrequency (RF) ablation. A difference in the responsiveness of normal and tumor blood vessels to vasoactive agents may be used to distinguish these regions in post-ablation follow-up. The goal of this study was to examine longitudinal perfusion changes in untreated viable tumor and the peripheral hyperemic rim of RF-ablated tumor in response to a vasoconstrictor (phenylephrine) or vasodilator (hydralazine) in a subcutaneous rat tumor model. MATERIALS AND METHODS Bilateral subcutaneous shoulder tumors were inoculated in 24 BDIX rats and evenly divided into two groups (phenylephrine and hydralazine groups). One tumor in each animal was completely treated with RF ablation (at 90 +/- 2 degrees C for 3 minutes), and the other remained untreated. Computed tomographic perfusion scans before and after phenylephrine (10 microg/kg) or hydralazine (5 mg/kg) administration were performed 2, 7, and 14 days after ablation. Four rats per group were euthanized on each scan day, and pathologic evaluation was performed. The changes of blood flow in the peripheral rim of ablated tumor and untreated viable tumor in response to phenylephrine or hydralazine at each time point were compared. The diagnostic accuracy of viable tumor using the percentage change of blood flow in response to phenylephrine and hydralazine was compared using receiver-operating characteristic analysis. RESULTS The peripheral rim of ablated tumor presented with a hyperemic reaction with dilated vessels and congestion on day 2 after ablation, numerous inflammatory vessels on day 7, and granulation tissue formation on day 14. Phenylephrine significantly decreased the blood flow in the peripheral hyperemic rim of ablated tumor on days 2, 7, and 14 by 16.3 +/- 9.7% (P = .001), 24.0 +/- 22.6% (P = .007), and 31.1 +/- 25.4% (P = .045), respectively. In untreated viable tumor, the change in blood flow after phenylephrine was irregular and insignificant. Hydralazine decreased the blood flow in the peripheral rim of both ablated tumor and untreated viable tumor. Receiver-operating characteristic analysis showed that reliable tumor diagnosis using the percentage change of blood flow in response to phenylephrine was noted on days 2 and 7, for which the areas under the curve were 0.82 (95% confidence interval, 0.64-1.00) and 0.81 (95% confidence interval, 0.56-1.00), respectively. However, tumor diagnosis using the blood flow change in response to hydralazine was unreliable. CONCLUSION Phenylephrine markedly decreased blood flow in the peripheral hyperemic rim of ablated tumor but had little effect on the untreated viable tumor. Computed tomographic perfusion with phenylephrine may be useful in the long-term treatment assessment of RF ablation.
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Thrombin promotes arteriogenesis and hemodynamic recovery in a rabbit hindlimb ischemia model. J Vasc Surg 2009; 49:1000-12. [PMID: 19217750 DOI: 10.1016/j.jvs.2008.11.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2008] [Revised: 10/30/2008] [Accepted: 11/02/2008] [Indexed: 12/15/2022]
Abstract
BACKGROUND Compared with angiogenesis, arteriogenesis is a distinct process based on the remodeling and maturation of pre-existing arterioles into large conductance arteries. Therapeutic angiogenesis has been proposed as a potential treatment for ischemic atherosclerotic diseases. Since a variety of angiogenic factors have been tested with inconsistent so far clinical results, the challenge remains in identifying the factor(s) that will stimulate functional neovascularization. Thrombin has been reported to play a pivotal role in the initiation of angiogenesis by regulating and organizing a network of angiogenic mediators. Also, it was recently demonstrated that thrombin is a potent anti-apoptotic factor for endothelial cells, providing evidence on a potential role of thrombin in vascular protection and maintenance of vessel integrity. Based on these observations, we hypothesized that thrombin may promote the development of mature functional blood vessels. METHODS Seventy-four (n=74) rabbits underwent bilateral femoral artery surgical excision. On the 20th postsurgical day increasing doses of VEGF or bFGF or thrombin were injected in one ischemic limb per rabbit and an equal volume of normal saline to the contralateral control limbs. Quantification of newly developed collateral vessels (diameter >500 mum) was performed by transauricular intra-arterial subtraction angiography. Computerized quantitative analysis of collateral vessels in angiography images was based on the concept of multiscale structural tensor. Perfusion analysis of an in vivo dynamic computed tomography study was performed to investigate hemodynamic recovery of the distal ischemic limbs. Tissue perfusion analysis was performed with the semiquantitative slope methodology, which focuses on the first-pass arterial phase. RESULTS A single administration of thrombin exhibited a dose-dependent increase of arteriogenic outcome. Thrombin at 5000 IU induced a 30.2 +/- 7.4% (P < 0.05) increase of total collateral area and length. Both VEGF and bFGF were without any significant effect at the concentrations used. Functional estimation of limb perfusion showed a statistically significant increase of blood flow recovery only for thrombin. The semiquantitative slope method perfusion score differed significantly in the 5000 IU thrombin treated limbs (5.7 +/- 0.3 vs 5.0 +/- 0.3 in control ischemic limbs; P < .05), and was not significantly inferior from the score of normal nonoperated limbs (6.5 +/- 0.3) suggesting a trend towards hemodynamic recovery of distal limb perfusion. CONCLUSIONS In a rabbit hindlimb ischemia model, thrombin promoted the formation of large collateral vessels and improved the perfusion of distal ischemic tissue. These results provide new insights in understanding the involvement of thrombin in vascular formation and point to a novel role of thrombin in arteriogenesis.
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Badea CT, Drangova M, Holdsworth DW, Johnson GA. In vivo small-animal imaging using micro-CT and digital subtraction angiography. Phys Med Biol 2008; 53:R319-50. [PMID: 18758005 DOI: 10.1088/0031-9155/53/19/r01] [Citation(s) in RCA: 170] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Small-animal imaging has a critical role in phenotyping, drug discovery and in providing a basic understanding of mechanisms of disease. Translating imaging methods from humans to small animals is not an easy task. The purpose of this work is to review in vivo x-ray based small-animal imaging, with a focus on in vivo micro-computed tomography (micro-CT) and digital subtraction angiography (DSA). We present the principles, technologies, image quality parameters and types of applications. We show that both methods can be used not only to provide morphological, but also functional information, such as cardiac function estimation or perfusion. Compared to other modalities, x-ray based imaging is usually regarded as being able to provide higher throughput at lower cost and adequate resolution. The limitations are usually associated with the relatively poor contrast mechanisms and potential radiation damage due to ionizing radiation, although the use of contrast agents and careful design of studies can address these limitations. We hope that the information will effectively address how x-ray based imaging can be exploited for successful in vivo preclinical imaging.
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Affiliation(s)
- C T Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University, Durham, NC 27710, USA
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Functional computed tomography imaging of tumor-induced angiogenesis: preliminary results of new tracer kinetic modeling using a computer discretization approach. ACTA ACUST UNITED AC 2008; 26:213-21. [DOI: 10.1007/s11604-007-0217-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2007] [Accepted: 12/06/2007] [Indexed: 12/22/2022]
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Jain R, Ellika SK, Scarpace L, Schultz LR, Rock JP, Gutierrez J, Patel SC, Ewing J, Mikkelsen T. Quantitative estimation of permeability surface-area product in astroglial brain tumors using perfusion CT and correlation with histopathologic grade. AJNR Am J Neuroradiol 2008; 29:694-700. [PMID: 18202239 PMCID: PMC7978188 DOI: 10.3174/ajnr.a0899] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2007] [Accepted: 10/17/2007] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Glioma angiogenesis and its different hemodynamic features, which can be evaluated by using perfusion CT (PCT) imaging of the brain, have been correlated with the grade and the aggressiveness of gliomas. Our hypothesis was that quantitative estimation of permeability surface area product (PS), cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) in astroglial brain tumors by using PCT will correlate with glioma grade. High-grade gliomas will show higher PS and CBV as compared with low-grade gliomas. MATERIALS AND METHODS PCT was performed in 32 patients with previously untreated astroglial tumors (24 high-grade gliomas and 8 low-grade gliomas) by using a total acquisition time of 170 seconds. World Health Organization (WHO) glioma grades were compared with PCT parameter absolute values by using Student or nonparametric Wilcoxon 2-sample tests. Receiver operating characteristic (ROC) analyses were also done for each of the parameters. RESULTS The differences in PS, CBV, and CBF between the low- and high-grade tumor groups were statistically significant, with the low-grade group showing lower mean values than the high-grade group. ROC analyses showed that both CBV (C-statistic 0.930) and PS (C-statistic 0.927) were very similar to each other in differentiating low- and high-grade gliomas and had higher predictability compared with CBF and MTT. Within the high-grade group, differentiation of WHO grade III and IV gliomas was also possible by using PCT parameters, and PS showed the highest C-statistic value (0.926) for the ROC analyses in this regard. CONCLUSIONS Both PS and CBV showed strong association with glioma grading, high-grade gliomas showing higher PS and CBV as compared with low-grade gliomas. Perfusion parameters, especially PS, can also be used to differentiate WHO grade III from grade IV in the high-grade tumor group.
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Affiliation(s)
- R Jain
- Division of Neuroradiology, Department of Radiology, Henry Ford Hospital, Detroit, MI 48202, USA.
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Liu Y, Bellomi M, Gatti G, Ping X. Accuracy of computed tomography perfusion in assessing metastatic involvement of enlarged axillary lymph nodes in patients with breast cancer. Breast Cancer Res 2008; 9:R40. [PMID: 17615058 PMCID: PMC2206711 DOI: 10.1186/bcr1738] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Revised: 06/13/2007] [Accepted: 07/05/2007] [Indexed: 12/24/2022] Open
Abstract
INTRODUCTION The purpose of this study was to evaluate the diagnostic accuracy of computed tomography (CT) perfusion in differentiating metastatic from inflammatory enlarged axillary lymph nodes in patients with breast cancer. METHODS Twenty-five patients with 26 locally advanced breast tumors and clinically palpable axillary lymph nodes underwent dynamic multi-detector CT (LightSpeed 16; General Electric Company) at one scan per second for 150 seconds at the same table position after 40 ml intravenous contrast injection at 4.0 ml/second. Semi-automatic calculation of values of perfusion parameters - blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS) - was performed. Results were compared with pathology and with Her-2/neu and Ki-67 levels in a surgical specimen of the primary tumor. RESULTS Examined lymph nodes were inflammatory in 8 cases and metastatic in 18. Mean values of perfusion parameters in inflammatory and metastatic nodes, respectively, were BF of 76.18 (confidence interval [CI], 31.53) and 161.60 (CI, 40.94) ml/100 mg per minute (p < 0.05), BV of 5.81 (CI, 2.50) and 9.15 (CI, 3.02) ml/100 mg (not significant [n.s.]), MTT of 6.80 (CI, 1.55) and 5.50 (CI, 1.84) seconds (p = 0.07), and PS of 25.82 (CI, 4.62) and 25.96 (CI, 7.47) ml/100 mg per minute (n.s.). Size of nodes, stage of breast cancer, Ki-67 and Her-2/neu levels in breast cancer, and expression of primary tumor activity were not correlated to any perfusion parameter in metastatic nodes. CONCLUSION CT perfusion might be an effective tool for studying enlarged axillary lymph nodes in patients with breast cancer. It gives information on vascularization of lymph nodes, helping to understand the changes occurring when neoplastic cells implant in lymph nodes.
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MESH Headings
- Adult
- Aged
- Axilla
- Breast Neoplasms/diagnostic imaging
- Breast Neoplasms/metabolism
- Breast Neoplasms/pathology
- Carcinoma, Ductal, Breast/diagnostic imaging
- Carcinoma, Ductal, Breast/metabolism
- Carcinoma, Ductal, Breast/secondary
- Carcinoma, Lobular/diagnostic imaging
- Carcinoma, Lobular/metabolism
- Carcinoma, Lobular/secondary
- Contrast Media
- Female
- Humans
- Ki-67 Antigen/metabolism
- Lymph Nodes/diagnostic imaging
- Lymphatic Metastasis
- Male
- Middle Aged
- Neoplasm Staging
- Perfusion
- Prospective Studies
- Receptor, ErbB-2/metabolism
- Regional Blood Flow
- Tomography, X-Ray Computed/methods
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Affiliation(s)
- Yun Liu
- Ningxia Medical College Hospital, Yinchuan, Ningxia, 75004, China
| | - Massimo Bellomi
- Department of Radiology, European Institute of Oncology and School of Medicine, University of Milan, Italy
| | - Giovanna Gatti
- Department of Senology, European Institute of Oncology, Milan, Italy
| | - Xuejun Ping
- Ningxia Medical College Hospital, Yinchuan, Ningxia, 75004, China
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Faria SC, Ng CS, Hess KR, Phongkitkarun S, Szejnfeld J, Daliani D, Charnsangavej C. CT Quantification of Effects of Thalidomide in Patients with Metastatic Renal Cell Carcinoma. AJR Am J Roentgenol 2007; 189:378-85. [PMID: 17646464 DOI: 10.2214/ajr.07.2164] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVE Our objective was to use functional CT to evaluate the effects of thalidomide in patients with metastatic renal cell carcinoma. SUBJECTS AND METHODS Patients with proven metastatic renal cell carcinoma were examined prospectively with functional CT. Functional CT studies (cine mode, 4 x 5 mm) were performed through the tumor after i.v. administration of a bolus of contrast material before and every 12 weeks after treatment with thalidomide. Quantitative values for blood flow, blood volume, mean transit time, and permeability-surface area product were calculated with commercial software. The average difference in percentage change in functional CT parameters from pretreatment to 12 and 24 weeks after treatment and the median difference in percentage change in functional CT parameters between response groups were assessed. We also tested whether percentage changes in functional CT parameters 12 weeks after treatment correlated with time to progression of disease and size of the perfused lesion. RESULTS Sixteen patients with a total of 23 tumors underwent at least one follow-up functional CT examination. Blood flow, blood volume, and permeability-surface area product decreased significantly 12 weeks (-18%, p = 0.0039; -15%, p = 0.0350; -24%, p = 0.0010) and 24 weeks (-28%, p = 0.017; -19%, p = 0.0300; -25%, p = 0.0031) after treatment with thalidomide. Time to progression correlated significantly with percentage change in blood flow (r = -0.34; p = 0.040) and permeability-surface area product (r = -0.36, p = 0.023) at 12 weeks. Responders had a significantly larger decrease in blood flow 12 weeks after treatment than did nonresponders (-29% vs -6%; p = 0.032). We also found a significant correlation between decrease in size of the perfused lesion and percentage decrease in blood flow 12 weeks after treatment (r = 0.50; p = 0.019). CONCLUSION Changes in functional CT parameters 12 weeks after treatment may be useful for monitoring the effects of thalidomide and predicting treatment outcome among patients with metastatic renal cell carcinoma. Further study with a larger clinical trial is needed.
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Affiliation(s)
- Silvana C Faria
- Department of Diagnostic Radiology, The University of Texas M. D. Anderson Cancer Center, Houston, TX, USA.
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Hirasawa H, Tsushima Y, Hirasawa S, Takei H, Taketomi-Takahasi A, Takano A, Amanuma M, Endo K. Perfusion CT of breast carcinoma: arterial perfusion of nonscirrhous carcinoma was higher than that of scirrhous carcinoma. Acad Radiol 2007; 14:547-52. [PMID: 17434068 DOI: 10.1016/j.acra.2007.01.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2006] [Revised: 01/12/2007] [Accepted: 01/14/2007] [Indexed: 11/16/2022]
Abstract
RATIONALE AND OBJECTIVES Our goals were to apply perfusion CT technique to breast tumor and to evaluate the correlation between arterial perfusion value and other tumor characteristics. MATERIALS AND METHODS Thirty-one female patients with primary breast tumors were included in this study. A single-slice dynamic CT was performed after an intravenous bolus injection of contrast material (40 ml; 370 mg I/ml) at 8 ml/sec. The parameters were calculated on a pixel-by-pixel basis by using maximum slope method, and quantitative maps of arterial perfusion were created. Statistical correlation between tumor size, patient age, and perfusion were assessed. Differences in perfusion between scirrhous and nonscirrhous carcinoma were also assessed. RESULTS Perfusion CT images were successfully created for 24 patients (mean age, 55.9 years old; range, 36-85 years). In five patients, dynamic CT was not performed due to lack of visualization of the breast tumor on unenhanced CT. In two patients, reliable perfusion CT image could not be created because of motion artifact. The mean perfusion for 24 tumors was 33.1 +/- 16.9 ml/min/100 ml (mean +/- SD; range, 14-78), and the tumor perfusion did not correlate with patient's age or tumor size (21.0 +/- 10.2 mm; range, 10-45 mm). The mean perfusion of nonscirrhous carcinoma (45.8 ml/min/100 ml; n = 11) was higher than that of scirrhous carcinoma (22.7 ml/min/100 ml; n = 11; P < .001). CONCLUSION Determination of the perfusion of breast carcinoma is feasible by dynamic CT and can be performed during a routine CT study without much supplementary burden on the patient. There are differences in blood flow between scirrhous and nonscirrhous breast carcinoma, and further research is needed to determine the impact of this finding.
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Affiliation(s)
- Hiromi Hirasawa
- Department of Diagnostic and Interventional Radiology, Gunma Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
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Chen L, Li T, Li R, Wei B, Peng Z. Alphastatin downregulates vascular endothelial cells sphingosine kinase activity and suppresses tumor growth in nude mice bearing human gastric cancer xenografts. World J Gastroenterol 2006; 12:4130-6. [PMID: 16830360 PMCID: PMC4087359 DOI: 10.3748/wjg.v12.i26.4130] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate whether alphastatin could inhibit human gastric cancer growth and furthermore whether sphingosine kinase (SPK) activity is involved in this process.
METHODS: Using migration assay, MTT assay and Matrigel assay, the effect of alphastatin on vascular endothelial cells (ECs) was evaluated in vitro. SPK and endothelial differentiation gene (EDG)-1, -3, -5 mRNAs were detected by reverse transcription-polymerase chain reaction (RT-PCR). SPK activity assay was used to evaluate the effect of alphastatin on ECs. Matrigel plug assay in nude mice was used to investigate the effect of alphastatin on angiogenesis in vivo. Female nude mice were subcutaneously implanted with human gastric cancer cells (BGC823) for the tumor xenografts studies. Micro vessel density was analyzed in Factor VIII-stained tumor sections by the immunohistochemical SP method.
RESULTS: In vitro, alphastatin inhibited the migration and tube formation of ECs, but had no effect on proliferation of ECs. RT-PCR analysis demonstrated that ECs expressed SPK and EDG-1, -3, -5 mRNAs. In vivo, alphastatin sufficiently suppressed neovascularization of the tumor in the nude mice. Daily administration of alphastatin produced significant tumor growth suppression. Immunohistochemical studies of tumor tissues revealed decreased micro vessel density in alphastatin-treated animals as compared with controls.
CONCLUSION: Downregulating ECs SPK activity may be one of the mechanisms that alphastatin inhibits gastric cancer angiogenesis. Alphastatin might be a useful and relatively nontoxic adjuvant therapy in the treatment of gastric cancer.
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MESH Headings
- Animals
- Antineoplastic Agents/pharmacology
- Cell Line, Tumor
- Cell Movement/drug effects
- Cell Proliferation/drug effects
- Cells, Cultured
- Drug Screening Assays, Antitumor
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/enzymology
- Female
- Fibrinogen/pharmacology
- Gene Expression Regulation, Enzymologic/drug effects
- Gene Expression Regulation, Enzymologic/physiology
- Humans
- Mice
- Mice, Nude
- Neovascularization, Pathologic/prevention & control
- Phosphotransferases (Alcohol Group Acceptor)/drug effects
- Phosphotransferases (Alcohol Group Acceptor)/genetics
- Phosphotransferases (Alcohol Group Acceptor)/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptors, Lysosphingolipid/genetics
- Receptors, Lysosphingolipid/metabolism
- Stomach Neoplasms/blood supply
- Stomach Neoplasms/pathology
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Affiliation(s)
- Lin Chen
- Department of General Surgery, General Hospital of Chinese PLA, Beijing 100853, China.
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27
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Stieger SM, Bloch SH, Foreman O, Wisner ER, Ferrara KW, Dayton PA. Ultrasound assessment of angiogenesis in a matrigel model in rats. ULTRASOUND IN MEDICINE & BIOLOGY 2006; 32:673-81. [PMID: 16677927 PMCID: PMC1636846 DOI: 10.1016/j.ultrasmedbio.2005.12.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2005] [Revised: 11/22/2005] [Accepted: 12/08/2005] [Indexed: 05/09/2023]
Abstract
Matrigel, a basement membrane extract, has been extensively used in in vivo angiogenesis. Contrast ultrasound imaging (CUI) of implanted Matrigel plugs with (+bFGF) and without basic fibroblast growth factor (-bFGF) was performed 7 and 14 d after implantation, followed by histologic analysis. Statistically significant differences between +bFGF and -bFGF plugs were apparent at d 7 in both plug size and contrast enhancement (both p < 0.05). Histopathology revealed differences in microvessel density (MVD) between +bFGF and -bFGF at d 7 and d 14. A significant correlation between MVD and both power Doppler contrast-enhanced area (r = 0.65, p < 0.05) and fraction of plug enhanced (r = 0.59, p < 0.05) was present. CUI of Matrigel plugs was shown to be a robust method for distinguishing between two different angiogenic states. Ultrasound measurements of blood flow in the plugs correlated with MVD, a histologic technique used to quantify tumor angiogenesis.
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Affiliation(s)
- Susanne M Stieger
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
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28
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Kan Z, Phongkitkarun S, Kobayashi S, Tang Y, Ellis LM, Lee TY, Charnsangavej C. Functional CT for Quantifying Tumor Perfusion in Antiangiogenic Therapy in a Rat Model. Radiology 2005; 237:151-8. [PMID: 16183931 DOI: 10.1148/radiol.2363041293] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
PURPOSE To determine the histologic basis of perfusion parameters measured at functional computed tomography (CT) and to examine the relationship between changes in perfusion and changes in histologic parameters after antiangiogenic therapy in a rat model. MATERIALS AND METHODS This study had institutional animal care and use committee approval. Among 20 Fischer rats with implanted FN13762 tumors in the liver, 10 were treated with SU5416, a tyrosine kinase inhibitor of vascular endothelial growth factor receptor, and 10 were treated with the diluent only as control rats. Six rats chosen at random from each group underwent functional CT for the measurement of tumor blood flow, blood volume, mean transit time, and permeability-surface area product. Tumor tissue slides corresponding to functional CT sections were examined to measure tumor microvascular density, number of luminal vessels, vascular perimeter, and vascular area. Two-tailed Student t testing was used to determine differences in growth, numbers of metastases to major organs, vascularity, and perfusion between SU5416-treated and control tumors. Pearson correlation coefficients were used to investigate relationships between vascular parameters. RESULTS Mean tumor volume and number of metastases, respectively, were lower in SU5416-treated rats than in control rats (1580 mm3 +/- 830 [standard deviation] vs 2330 mm3 +/- 960 and 22.4 +/- 11.0 vs 35.2 +/- 17.3); however, these differences were not significant (P = .084 and P = .079). Mean tumor microvascular density was significantly lower in SU5416-treated rats than in control rats (6.4 vessels per field +/- 4.6 vs 17.2 vessels per field +/- 7.5, P < .001); however, vessel perimeter and vessel area, respectively, were significantly larger in treated rats than in control rats (470 microm per field +/- 320 vs 360 microm per field +/- 270, P = .02; and 4010 microm2 per field +/- 2990 vs 2230 microm2 per field +/- 1750, P = .001). Significant correlations were observed between microvascular density and vessel perimeter and area (r = 0.59 and r = 0.25, respectively; P < .01 for both) in SU5416-treated tumors but not control tumors. Blood flow, blood volume, and permeability-surface area product at functional CT were significantly higher in SU5416-treated tumors than in control tumors (P < .001 for all). CONCLUSION These results validate the idea that functional CT can help quantify the perfusion function of mature vessels but not changes in microvessel density in antiangiogenic therapy.
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Affiliation(s)
- Zuxing Kan
- Department of Diagnostic Radiology, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA.
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29
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Rouet V, Hamma-Kourbali Y, Petit E, Panagopoulou P, Katsoris P, Barritault D, Caruelle JP, Courty J. A synthetic glycosaminoglycan mimetic binds vascular endothelial growth factor and modulates angiogenesis. J Biol Chem 2005; 280:32792-800. [PMID: 16014624 DOI: 10.1074/jbc.m504492200] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
In a previous study, we showed that in situ injection of glycosaminoglycan mimetics called RGTAs (ReGeneraTing Agents) enhanced neovascularization after skeletal muscular ischemia (Desgranges, P., Barbaud, C., Caruelle, J. P., Barritault, D., and Gautron, J. (1999) FASEB J. 13, 761-766). In the present study, we showed that the RGTA OTR4120 modulated angiogenesis in the chicken embryo chorioallantoic membrane assay, in a dose-dependent manner. We therefore investigated the effect of OTR4120 on one of the most specific angiogenesis-regulating heparin-binding growth factors, vascular endothelial growth factor 165 (VEGF165). OTR4120 showed high affinity binding to VEGF165 (Kd = 2.2 nm), as compared with heparin (Kd = 15 nm), and potentiated the affinity of VEGF165 for VEGF receptor-1 and -2 and for neuropilin-1. In vitro, OTR4120 potentiated VEGF165-induced proliferation and migration of human umbilical vein endothelial cells. In the in vivo Matrigel plug angiogenesis assay, OTR4120 in a concentration as low as 3 ng/ml caused a 6-fold increase in VEGF165-induced angiogenesis. Immunohistochemical staining showed a larger number of well differentiated VEGFR-2-expressing-cells in Matrigel sections of OTR4120-treated plug than in control sections. These findings indicate that OTR4120 enhances the VEGF165-induced angiogenesis and therefore may hold promise for treating disorders characterized by deficient angiogenesis.
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Affiliation(s)
- Vincent Rouet
- Laboratoire de Recherche sur la Croissance Cellulaire, la Réparation et la Régénération Tissulaires UMR CNRS 7149, Université Paris XII-Val de Marne, Avenue du Général de Gaulle, 94010 Créteil CEDEX, France
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