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Mazaheri Y, Kim N, Lakhman Y, Jafari R, Vargas A, Otazo R. Dynamic contrast-enhanced MRI parametric mapping using high spatiotemporal resolution Golden-angle RAdial Sparse Parallel MRI and iterative joint estimation of the arterial input function and pharmacokinetic parameters. NMR IN BIOMEDICINE 2022; 35:e4718. [PMID: 35226774 PMCID: PMC9203940 DOI: 10.1002/nbm.4718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 02/17/2022] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
The aim of this work is to develop a data-driven quantitative dynamic contrast-enhanced (DCE) MRI technique using Golden-angle RAdial Sparse Parallel (GRASP) MRI with high spatial resolution and high flexible temporal resolution and pharmacokinetic (PK) analysis with an arterial input function (AIF) estimated directly from the data obtained from each patient. DCE-MRI was performed on 13 patients with gynecological malignancy using a 3-T MRI scanner with a single continuous golden-angle stack-of-stars acquisition and image reconstruction with two temporal resolutions, by exploiting a unique feature in GRASP that reconstructs acquired data with user-defined temporal resolution. Joint estimation of the AIF (both AIF shape and delay) and PK parameters was performed with an iterative algorithm that alternates between AIF and PK estimation. Computer simulations were performed to determine the accuracy (expressed as percentage error [PE]) and precision of the estimated parameters. PK parameters (volume transfer constant [Ktrans ], fractional volume of the extravascular extracellular space [ve ], and blood plasma volume fraction [vp ]) and normalized root-mean-square error [nRMSE] (%) of the fitting errors for the tumor contrast kinetic data were measured both with population-averaged and data-driven AIFs. On patient data, the Wilcoxon signed-rank test was performed to compare nRMSE. Simulations demonstrated that GRASP image reconstruction with a temporal resolution of 1 s/frame for AIF estimation and 5 s/frame for PK analysis resulted in an absolute PE of less than 5% in the estimation of Ktrans and ve , and less than 11% in the estimation of vp . The nRMSE (mean ± SD) for the dual temporal resolution image reconstruction and data-driven AIF was 0.16 ± 0.04 compared with 0.27 ± 0.10 (p < 0.001) with 1 s/frame using population-averaged AIF, and 0.23 ± 0.07 with 5 s/frame using population-averaged AIF (p < 0.001). We conclude that DCE-MRI data acquired and reconstructed with the GRASP technique at dual temporal resolution can successfully be applied to jointly estimate the AIF and PK parameters from a single acquisition resulting in data-driven AIFs and voxelwise PK parametric maps.
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Affiliation(s)
- Yousef Mazaheri
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Nathanael Kim
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Yulia Lakhman
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Ramin Jafari
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Alberto Vargas
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Ricardo Otazo
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York, USA
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
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Easley TO, Ren Z, Kim B, Karczmar GS, Barber RF, Pineda FD. Enhancement-constrained acceleration: A robust reconstruction framework in breast DCE-MRI. PLoS One 2021; 16:e0258621. [PMID: 34710110 PMCID: PMC8553053 DOI: 10.1371/journal.pone.0258621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 10/01/2021] [Indexed: 02/08/2023] Open
Abstract
In patients with dense breasts or at high risk of breast cancer, dynamic contrast enhanced MRI (DCE-MRI) is a highly sensitive diagnostic tool. However, its specificity is highly variable and sometimes low; quantitative measurements of contrast uptake parameters may improve specificity and mitigate this issue. To improve diagnostic accuracy, data need to be captured at high spatial and temporal resolution. While many methods exist to accelerate MRI temporal resolution, not all are optimized to capture breast DCE-MRI dynamics. We propose a novel, flexible, and powerful framework for the reconstruction of highly-undersampled DCE-MRI data: enhancement-constrained acceleration (ECA). Enhancement-constrained acceleration uses an assumption of smooth enhancement at small time-scale to estimate points of smooth enhancement curves in small time intervals at each voxel. This method is tested in silico with physiologically realistic virtual phantoms, simulating state-of-the-art ultrafast acquisitions at 3.5s temporal resolution reconstructed at 0.25s temporal resolution (demo code available here). Virtual phantoms were developed from real patient data and parametrized in continuous time with arterial input function (AIF) models and lesion enhancement functions. Enhancement-constrained acceleration was compared to standard ultrafast reconstruction in estimating the bolus arrival time and initial slope of enhancement from reconstructed images. We found that the ECA method reconstructed images at 0.25s temporal resolution with no significant loss in image fidelity, a 4x reduction in the error of bolus arrival time estimation in lesions (p < 0.01) and 11x error reduction in blood vessels (p < 0.01). Our results suggest that ECA is a powerful and versatile tool for breast DCE-MRI.
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Affiliation(s)
- Ty O. Easley
- McKelvey School of Engineering, Washington University in St. Louis, St. Louis, Missouri, United States of America
| | - Zhen Ren
- Department of Radiology, University of Chicago, Chicago, Illinois, United States of America
| | - Byol Kim
- Department of Biostatistics at the University of Washington, Seattle, Washington, United States of America
| | - Gregory S. Karczmar
- Department of Radiology, University of Chicago, Chicago, Illinois, United States of America
| | - Rina F. Barber
- Department of Statistics, University of Chicago, Chicago, Illinois, United States of America
| | - Federico D. Pineda
- Department of Radiology, University of Chicago, Chicago, Illinois, United States of America
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Gwilliam MN, Collins DJ, Leach MO, Orton MR. Quantifying MRI T1 relaxation in flowing blood: implications for arterial input function measurement in DCE-MRI. Br J Radiol 2021; 94:20191004. [PMID: 33507818 PMCID: PMC8011233 DOI: 10.1259/bjr.20191004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVES To investigate the feasibility of accurately quantifying the concentration of MRI contrast agent in flowing blood by measuring its T1 in a large vessel. Such measures are often used to obtain patient-specific arterial input functions for the accurate fitting of pharmacokinetic models to dynamic contrast enhanced MRI data. Flow is known to produce errors with this technique, but these have so far been poorly quantified and characterised in the context of pulsatile flow with a rapidly changing T1 as would be expected in vivo. METHODS A phantom was developed which used a mechanical pump to pass fluid at physiologically relevant rates. Measurements of T1 were made using high temporal resolution gradient recalled sequences suitable for DCE-MRI of both constant and pulsatile flow. These measures were used to validate a virtual phantom that was then used to simulate the expected errors in the measurement of an AIF in vivo. RESULTS The relationship between measured T1 values and flow velocity was found to be non-linear. The subsequent error in quantification of contrast agent concentration in a measured AIF was shown. CONCLUSIONS The T1 measurement of flowing blood using standard DCE- MRI sequences are subject to large measurement errors which are non-linear in relation to flow velocity. ADVANCES IN KNOWLEDGE This work qualitatively and quantitatively demonstrates the difficulties of accurately measuring the T1 of flowing blood using DCE-MRI over a wide range of physiologically realistic flow velocities and pulsatilities. Sources of error are identified and proposals made to reduce these.
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Affiliation(s)
- Matthew N Gwilliam
- CRUK Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden NHS Trust, London, UK
| | - David J Collins
- CRUK Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden NHS Trust, London, UK
| | - Martin O Leach
- CRUK Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden NHS Trust, London, UK
| | - Matthew R Orton
- CRUK Cancer Imaging Centre, Institute of Cancer Research and Royal Marsden NHS Trust, London, UK
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Gallagher FA, Woitek R, McLean MA, Gill AB, Manzano Garcia R, Provenzano E, Riemer F, Kaggie J, Chhabra A, Ursprung S, Grist JT, Daniels CJ, Zaccagna F, Laurent MC, Locke M, Hilborne S, Frary A, Torheim T, Boursnell C, Schiller A, Patterson I, Slough R, Carmo B, Kane J, Biggs H, Harrison E, Deen SS, Patterson A, Lanz T, Kingsbury Z, Ross M, Basu B, Baird R, Lomas DJ, Sala E, Wason J, Rueda OM, Chin SF, Wilkinson IB, Graves MJ, Abraham JE, Gilbert FJ, Caldas C, Brindle KM. Imaging breast cancer using hyperpolarized carbon-13 MRI. Proc Natl Acad Sci U S A 2020; 117:2092-2098. [PMID: 31964840 PMCID: PMC6995024 DOI: 10.1073/pnas.1913841117] [Citation(s) in RCA: 111] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Our purpose is to investigate the feasibility of imaging tumor metabolism in breast cancer patients using 13C magnetic resonance spectroscopic imaging (MRSI) of hyperpolarized 13C label exchange between injected [1-13C]pyruvate and the endogenous tumor lactate pool. Treatment-naïve breast cancer patients were recruited: four triple-negative grade 3 cancers; two invasive ductal carcinomas that were estrogen and progesterone receptor-positive (ER/PR+) and HER2/neu-negative (HER2-), one grade 2 and one grade 3; and one grade 2 ER/PR+ HER2- invasive lobular carcinoma (ILC). Dynamic 13C MRSI was performed following injection of hyperpolarized [1-13C]pyruvate. Expression of lactate dehydrogenase A (LDHA), which catalyzes 13C label exchange between pyruvate and lactate, hypoxia-inducible factor-1 (HIF1α), and the monocarboxylate transporters MCT1 and MCT4 were quantified using immunohistochemistry and RNA sequencing. We have demonstrated the feasibility and safety of hyperpolarized 13C MRI in early breast cancer. Both intertumoral and intratumoral heterogeneity of the hyperpolarized pyruvate and lactate signals were observed. The lactate-to-pyruvate signal ratio (LAC/PYR) ranged from 0.021 to 0.473 across the tumor subtypes (mean ± SD: 0.145 ± 0.164), and a lactate signal was observed in all of the grade 3 tumors. The LAC/PYR was significantly correlated with tumor volume (R = 0.903, P = 0.005) and MCT 1 (R = 0.85, P = 0.032) and HIF1α expression (R = 0.83, P = 0.043). Imaging of hyperpolarized [1-13C]pyruvate metabolism in breast cancer is feasible and demonstrated significant intertumoral and intratumoral metabolic heterogeneity, where lactate labeling correlated with MCT1 expression and hypoxia.
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Affiliation(s)
- Ferdia A Gallagher
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
- Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - Ramona Woitek
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom;
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, 1090 Vienna, Austria
| | - Mary A McLean
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - Andrew B Gill
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Raquel Manzano Garcia
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - Elena Provenzano
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Cambridge Breast Cancer Research Unit, Addenbrooke's Hospital, Cambridge University Hospital National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
- Department of Histopathology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - Frank Riemer
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Joshua Kaggie
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Anita Chhabra
- Pharmacy Department, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge, United Kingdom
| | - Stephan Ursprung
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - James T Grist
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Charlie J Daniels
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Fulvio Zaccagna
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | | | - Matthew Locke
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Sarah Hilborne
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Amy Frary
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Turid Torheim
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - Chris Boursnell
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - Amy Schiller
- Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - Ilse Patterson
- Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - Rhys Slough
- Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - Bruno Carmo
- Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - Justine Kane
- Cambridge Breast Cancer Research Unit, Addenbrooke's Hospital, Cambridge University Hospital National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - Heather Biggs
- Cambridge Breast Cancer Research Unit, Addenbrooke's Hospital, Cambridge University Hospital National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - Emma Harrison
- Cambridge Breast Cancer Research Unit, Addenbrooke's Hospital, Cambridge University Hospital National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - Surrin S Deen
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Andrew Patterson
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
- Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - Titus Lanz
- RAPID Biomedical GmbH, 97222 Rimpar, Germany
| | - Zoya Kingsbury
- Medical Genomics Research, Illumina, Great Abington, Cambridge CB21 6DF, United Kingdom
| | - Mark Ross
- Medical Genomics Research, Illumina, Great Abington, Cambridge CB21 6DF, United Kingdom
| | - Bristi Basu
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Department of Oncology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Richard Baird
- Cambridge Breast Cancer Research Unit, Addenbrooke's Hospital, Cambridge University Hospital National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - David J Lomas
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Evis Sala
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
- Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - James Wason
- Medical Research Council Biostatistics Unit, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
- Institute of Health and Society, Newcastle University, Newcastle-upon-Tyne NE2 4AX, United Kingdom
| | - Oscar M Rueda
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - Suet-Feung Chin
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - Ian B Wilkinson
- Department of Experimental Medicine and Immunotherapeutics, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Martin J Graves
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
- Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
| | - Jean E Abraham
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Cambridge Breast Cancer Research Unit, Addenbrooke's Hospital, Cambridge University Hospital National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
- Department of Oncology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Fiona J Gilbert
- Department of Radiology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
- Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
| | - Carlos Caldas
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Cambridge Breast Cancer Research Unit, Addenbrooke's Hospital, Cambridge University Hospital National Health Service Foundation Trust, Cambridge CB2 0QQ, United Kingdom
- Department of Oncology, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
| | - Kevin M Brindle
- Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- Department of Biochemistry, University of Cambridge, Cambridge CB2 0QQ, United Kingdom
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Abstract
Dynamic contrast-enhanced MRI in pre-clinical imaging allows the in-vivo monitoring of vascular, physiological properties in normal and diseased tissue. There is considerable variation in the methods employed owing to the different questions that can be asked and answered about the physiologic alterations as well as morphologic changes in tissue. Here we review the typical decisions in the design and execution of a dynamic contrast-enhanced MRI study in mice although the findings can easily be transferred to other species. Emphasis is placed on highlighting the many pitfalls that wait for the unaware pre-clinical MRI practitioner and that go often unmentioned in the abundant literature dealing with dynamic contrast-enhanced MRI in animal models.
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Winter JD, Moraes FY, Chung C, Coolens C. Detectability of radiation-induced changes in magnetic resonance biomarkers following stereotactic radiosurgery: A pilot study. PLoS One 2018; 13:e0207933. [PMID: 30475887 PMCID: PMC6258119 DOI: 10.1371/journal.pone.0207933] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 11/05/2018] [Indexed: 11/18/2022] Open
Abstract
Our objective was to investigate direct voxel-wise relationship between dose and early MR biomarker changes both within and in the high-dose region surrounding brain metastases following stereotactic radiosurgery (SRS). Specifically, we examined the apparent diffusion coefficient (ADC) from diffusion-weighted imaging and the contrast transfer coefficient (Ktrans) and volume of extracellular extravascular space (ve) derived from dynamic contrast-enhanced (DCE) MRI data. We investigated 29 brain metastases in 18 patients using 3 T MRI to collect imaging data at day 0, day 3 and day 20 following SRS. The ADC maps were generated by the scanner and Ktrans and ve maps were generated using in-house software for dynamic tracer-kinetic analysis. To enable spatially-correlated voxel-wise analysis, we developed a registration pipeline to register all ADC, Ktrans and ve maps to the planning MRI scan. To interrogate longitudinal changes, we computed absolute ΔADC, ΔKtrans and Δve for day 3 and 20 post-SRS relative to day 0. We performed a Kruskall-Wallice test on each biomarker between time points and investigated dose correlations within the gross tumour volume (GTV) and surrounding high dose region > 12 Gy via Spearman’s rho. Only ve exhibited significant differences between day 0 and 20 (p < 0.005) and day 3 and 20 (p < 0.05) within the GTV following SRS. Strongest dose correlations were observed for ADC within the GTV (rho = 0.17 to 0.20) and weak correlations were observed for ADC and Ktrans in the surrounding > 12 Gy region. Both ΔKtrans and Δve showed a trend with dose at day 20 within the GTV and > 12 Gy region (rho = -0.04 to -0.16). Weak dose-related decreases in Ktrans and ve within the GTV and high dose region at day 20 most likely reflect underlying vascular responses to radiation. Our study also provides a voxel-wise analysis schema for future MR biomarker studies with the goal of elucidating surrogates for radionecrosis.
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Affiliation(s)
- Jeff D. Winter
- Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario, Canada
| | - Fabio Y. Moraes
- Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario, Canada
| | - Caroline Chung
- Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- TECHNA Institute, University Health Network, Toronto, Ontario, Canada
| | - Catherine Coolens
- Radiation Medicine Program, Princess Margaret Cancer Center and University Health Network, Toronto, Ontario, Canada
- TECHNA Institute, University Health Network, Toronto, Ontario, Canada
- Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Ontario, Canada
- * E-mail:
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Pineda FD, Easley TO, Karczmar GS. Dynamic field-of-view imaging to increase temporal resolution in the early phase of contrast media uptake in breast DCE-MRI: A feasibility study. Med Phys 2018; 45:1050-1058. [PMID: 29314060 PMCID: PMC6028013 DOI: 10.1002/mp.12747] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 12/14/2017] [Accepted: 12/15/2017] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To increase diagnostic accuracy of breast MRI by increasing temporal resolution and more accurately sampling the early kinetics of contrast media uptake. We tested the feasibility of accelerating bilateral breast DCE-MRI by reducing the FOV, allowing aliasing, and unfolding the resulting images. METHODS Previous experience with an "ultrafast" protocol for bilateral breast DCE-MRI (6-10 s temporal resolution) showed that the number of significantly enhancing voxels is very low in the first 30-45 s after contrast media injection. This suggests that overlap of enhancing voxels in aliased images will be very infrequent. Therefore, aliased images can be acquired during the first 30-45 s after contrast media injection and unfolded to produce full-FOV images with few errors. In a proof-of-principle test, aliased images were simulated from the first 30 s of full-FOV acquisitions. Cases with relatively dense early enhancement were selected to test this method in a worst-case scenario. In an initial test, an FOV of 60% the size of the full FOV was simulated. To reduce the probability of errors due to overlapping voxels in aliased images, we then tested a dynamic FOV approach. The FOV was progressively increased so that enhancing voxels could not overlap at multiple time-points, and areas where enhancing voxels overlapped at a given time-point could be unfolded by interpolating between the preceding and subsequent time-points (acquired with different FOVs). The simulated FOV sizes for each of the time-points were 31%, 44%, and 77% of the full FOV. Subtraction images (post- minus precontrast) were generated for aliased images and filtered to select significantly enhancing voxels. Comparison of early, highly aliased images, with later, less aliased images then helped to identify the true locations of enhancing voxels. RESULTS In the initial aliasing simulations, an average of 2.9% of the enhancing voxels above the chest wall overlapped in the aliased images (range 0.1%-6.7%). The similarity between simulated unfolded images and the correct full-FOV images, evaluated using CW-SSIM (complex wavelet similarity index), was 0.50 ± 0.26, 0.76 ± 0.09, and 0.80 ± 0.10 for the first, second, and third time-point, respectively (numbers closer to 1 indicate more similar images). For the dynamic FOV tests, an average of 11% of the enhancing voxels above the chest wall overlapped (range 0%-40%) due to greater aliasing at early time-points. Despite more voxels overlapping, the CW-SSIM values for the data acquired with dynamic FOVs were 0.64 ± 0.25, 0.93 ± 0.04, and 0.97 ± 0.02 for the first, second, and third time-points, respectively. CONCLUSIONS Dynamic FOV imaging allows accelerated bilateral breast DCE-MRI during the early contrast media uptake phase. This method relies on the sparsity of enhancement at the early phases of DCE-MRI of the breast. The results of simulations suggest that dynamic FOV imaging and unfolding produces images that are very close to fully sampled images, and allows temporal resolution as high as 2 s per image.
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Affiliation(s)
| | - Ty O Easley
- Department of RadiologyThe University of ChicagoChicagoIL60637USA
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Milenković J, Dalmış MU, Žgajnar J, Platel B. Textural analysis of early-phase spatiotemporal changes in contrast enhancement of breast lesions imaged with an ultrafast DCE-MRI protocol. Med Phys 2017. [PMID: 28622412 DOI: 10.1002/mp.12408] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
PURPOSE New ultrafast view-sharing sequences have enabled breast dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to be performed at high spatial and temporal resolution. The aim of this study is to evaluate the diagnostic potential of textural features that quantify the spatiotemporal changes of the contrast-agent uptake in computer-aided diagnosis of malignant and benign breast lesions imaged with high spatial and temporal resolution DCE-MRI. METHOD The proposed approach is based on the textural analysis quantifying the spatial variation of six dynamic features of the early-phase contrast-agent uptake of a lesion's largest cross-sectional area. The textural analysis is performed by means of the second-order gray-level co-occurrence matrix, gray-level run-length matrix and gray-level difference matrix. This yields 35 textural features to quantify the spatial variation of each of the six dynamic features, providing a feature set of 210 features in total. The proposed feature set is evaluated based on receiver operating characteristic (ROC) curve analysis in a cross-validation scheme for random forests (RF) and two support vector machine classifiers, with linear and radial basis function (RBF) kernel. Evaluation is done on a dataset with 154 breast lesions (83 malignant and 71 benign) and compared to a previous approach based on 3D morphological features and the average and standard deviation of the same dynamic features over the entire lesion volume as well as their average for the smaller region of the strongest uptake rate. RESULT The area under the ROC curve (AUC) obtained by the proposed approach with the RF classifier was 0.8997, which was significantly higher (P = 0.0198) than the performance achieved by the previous approach (AUC = 0.8704) on the same dataset. Similarly, the proposed approach obtained a significantly higher result for both SVM classifiers with RBF (P = 0.0096) and linear kernel (P = 0.0417) obtaining AUC of 0.8876 and 0.8548, respectively, compared to AUC values of previous approach of 0.8562 and 0.8311, respectively. CONCLUSION The proposed approach based on 2D textural features quantifying spatiotemporal changes of the contrast-agent uptake significantly outperforms the previous approach based on 3D morphology and dynamic analysis in differentiating the malignant and benign breast lesions, showing its potential to aid clinical decision making.
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Affiliation(s)
- Jana Milenković
- Faculty for Electrical Engineering, University of Ljubljana, Tržaška 25, 1000, Ljubljana, Slovenia.,Faculty of Medicine, University of Ljubljana, Vražov trg 2, 1000, Ljubljana, Slovenia
| | - Mehmet Ufuk Dalmış
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Geert Grooteplein 10, Route 766, Nijmegen, Gelderland, 6500 HB, the Netherlands
| | - Janez Žgajnar
- Institute of Oncology, Zaloška 2, 1000, Ljubljana, Slovenia
| | - Bram Platel
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Geert Grooteplein 10, Route 766, Nijmegen, Gelderland, 6500 HB, the Netherlands
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Joo IL, Lai AY, Bazzigaluppi P, Koletar MM, Dorr A, Brown ME, Thomason LAM, Sled JG, McLaurin J, Stefanovic B. Early neurovascular dysfunction in a transgenic rat model of Alzheimer's disease. Sci Rep 2017; 7:46427. [PMID: 28401931 PMCID: PMC5388880 DOI: 10.1038/srep46427] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 03/20/2017] [Indexed: 01/06/2023] Open
Abstract
Alzheimer's disease (AD), pathologically characterized by amyloid-β peptide (Aβ) accumulation, neurofibrillary tangle formation, and neurodegeneration, is thought to involve early-onset neurovascular abnormalities. Hitherto studies on AD-associated neurovascular injury have used animal models that exhibit only a subset of AD-like pathologies and demonstrated some Aβ-dependent vascular dysfunction and destabilization of neuronal network. The present work focuses on the early stage of disease progression and uses TgF344-AD rats that recapitulate a broader repertoire of AD-like pathologies to investigate the cerebrovascular and neuronal network functioning using in situ two-photon fluorescence microscopy and laminar array recordings of local field potentials, followed by pathological analyses of vascular wall morphology, tau hyperphosphorylation, and amyloid plaques. Concomitant to widespread amyloid deposition and tau hyperphosphorylation, cerebrovascular reactivity was strongly attenuated in cortical penetrating arterioles and venules of TgF344-AD rats in comparison to those in non-transgenic littermates. Blood flow elevation to hypercapnia was abolished in TgF344-AD rats. Concomitantly, the phase-amplitude coupling of the neuronal network was impaired, evidenced by decreased modulation of theta band phase on gamma band amplitude. These results demonstrate significant neurovascular network dysfunction at an early stage of AD-like pathology. Our study identifies early markers of pathology progression and call for development of combinatorial treatment plans.
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Affiliation(s)
- Illsung L. Joo
- Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, Ontario, M5G 2M9, Canada
- Sunnybrook Health Sciences Center, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - Aaron Y. Lai
- Sunnybrook Health Sciences Center, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - Paolo Bazzigaluppi
- Fundamental Neurobiology, Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, Ontario, M5T 2R1, Canada
| | - Margaret M. Koletar
- Sunnybrook Health Sciences Center, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - Adrienne Dorr
- Sunnybrook Health Sciences Center, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - Mary E. Brown
- Sunnybrook Health Sciences Center, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - Lynsie A. M. Thomason
- Sunnybrook Health Sciences Center, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - John G. Sled
- Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, Ontario, M5G 2M9, Canada
- Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1X8, Canada
| | - JoAnne McLaurin
- Sunnybrook Health Sciences Center, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, 1 King’s College Circle, Toronto, Ontario, M5S 1A1, Canada
| | - Bojana Stefanovic
- Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, Ontario, M5G 2M9, Canada
- Sunnybrook Health Sciences Center, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
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10
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Dorr A, Thomason LA, Koletar MM, Joo IL, Steinman J, Cahill LS, Sled JG, Stefanovic B. Effects of voluntary exercise on structure and function of cortical microvasculature. J Cereb Blood Flow Metab 2017; 37:1046-1059. [PMID: 27683451 PMCID: PMC5363487 DOI: 10.1177/0271678x16669514] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Aerobic activity has been shown highly beneficial to brain health, yet much uncertainty still surrounds the effects of exercise on the functioning of cerebral microvasculature. This study used two-photon fluorescence microscopy to examine cerebral hemodynamic alterations as well as accompanying geometric changes in the cortical microvascular network following five weeks of voluntary exercise in transgenic mice endogenously expressing tdTomato in vascular endothelial cells to allow visualization of microvessels irrespective of their perfusion levels. We found a diminished microvascular response to a hypercapnic challenge (10% FiCO2) in running mice when compared to that in nonrunning controls despite commensurate increases in transcutaneous CO2 tension. The flow increase to hypercapnia in runners was 70% lower than that in nonrunners (p = 0.0070) and the runners' arteriolar red blood cell speed changed by only half the amount seen in nonrunners (p = 0.0085). No changes were seen in resting hemodynamics or in the systemic physiological parameters measured. Although a few unperfused new vessels were observed on visual inspection, running did not produce significant morphological differences in the microvascular morphometric parameters, quantified following semiautomated tracking of the microvascular networks. We propose that voluntary running led to increased cortical microvascular efficiency and desensitization to CO2 elevation.
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Affiliation(s)
| | | | | | - Illsung L Joo
- 1 Sunnybrook Research Institute, Toronto, Canada.,2 Department of Medical Biophysics, University of Toronto, Toronto, Canada
| | - Joe Steinman
- 2 Department of Medical Biophysics, University of Toronto, Toronto, Canada.,3 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Canada
| | - Lindsay S Cahill
- 3 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Canada
| | - John G Sled
- 2 Department of Medical Biophysics, University of Toronto, Toronto, Canada.,3 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Canada
| | - Bojana Stefanovic
- 1 Sunnybrook Research Institute, Toronto, Canada.,2 Department of Medical Biophysics, University of Toronto, Toronto, Canada
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11
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Pineda FD, Medved M, Wang S, Fan X, Schacht DV, Sennett C, Oto A, Newstead GM, Abe H, Karczmar GS. Ultrafast Bilateral DCE-MRI of the Breast with Conventional Fourier Sampling: Preliminary Evaluation of Semi-quantitative Analysis. Acad Radiol 2016; 23:1137-44. [PMID: 27283068 PMCID: PMC4987200 DOI: 10.1016/j.acra.2016.04.008] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 01/27/2016] [Accepted: 04/12/2016] [Indexed: 12/25/2022]
Abstract
RATIONALE AND OBJECTIVES The study aimed to evaluate the feasibility and advantages of a combined high temporal and high spatial resolution protocol for dynamic contrast-enhanced magnetic resonance imaging of the breast. MATERIALS AND METHODS Twenty-three patients with enhancing lesions were imaged at 3T. The acquisition protocol consisted of a series of bilateral, fat-suppressed "ultrafast" acquisitions, with 6.9- to 9.9-second temporal resolution for the first minute following contrast injection, followed by four high spatial resolution acquisitions with 60- to 79.5-second temporal resolution. All images were acquired with standard uniform Fourier sampling. A filtering method was developed to reduce noise and detect significant enhancement in the high temporal resolution images. Time of arrival (TOA) was defined as the time at which each voxel first satisfied all the filter conditions, relative to the time of initial arterial enhancement. RESULTS Ultrafast images improved visualization of the vasculature feeding and draining lesions. A small percentage of the entire field of view (<6%) enhanced significantly in the 30 seconds following contrast injection. Lesion conspicuity was highest in early ultrafast images, especially in cases with marked parenchymal enhancement. Although the sample size was relatively small, the average TOA for malignant lesions was significantly shorter than the TOA for benign lesions. Significant differences were also measured in other parameters descriptive of early contrast media uptake kinetics (P < 0.05). CONCLUSIONS Ultrafast imaging in the first minute of dynamic contrast-enhanced magnetic resonance imaging of the breast has the potential to add valuable information on early contrast dynamics. Ultrafast imaging could allow radiologists to confidently identify lesions in the presence of marked background parenchymal enhancement.
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Affiliation(s)
- Federico D Pineda
- Department of Radiology, University of Chicago, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637
| | - Milica Medved
- Department of Radiology, University of Chicago, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637
| | - Shiyang Wang
- Department of Radiology, University of Chicago, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637
| | - Xiaobing Fan
- Department of Radiology, University of Chicago, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637
| | - David V Schacht
- Department of Radiology, University of Chicago, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637
| | - Charlene Sennett
- Department of Radiology, University of Chicago, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637
| | - Aytekin Oto
- Department of Radiology, University of Chicago, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637
| | - Gillian M Newstead
- Department of Radiology, University of Chicago, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637
| | - Hiroyuki Abe
- Department of Radiology, University of Chicago, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637
| | - Gregory S Karczmar
- Department of Radiology, University of Chicago, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637.
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12
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Rata M, Collins DJ, Darcy J, Messiou C, Tunariu N, Desouza N, Young H, Leach MO, Orton MR. Assessment of repeatability and treatment response in early phase clinical trials using DCE-MRI: comparison of parametric analysis using MR- and CT-derived arterial input functions. Eur Radiol 2016; 26:1991-8. [PMID: 26385804 PMCID: PMC4902841 DOI: 10.1007/s00330-015-4012-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 08/07/2015] [Accepted: 09/03/2015] [Indexed: 01/08/2023]
Abstract
OBJECTIVES Pharmacokinetic (PK) modelling of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) data requires a reliable measure of the arterial input function (AIF) to robustly characterise tumour vascular properties. This study compared repeatability and treatment-response effects of DCE-MRI-derived PK parameters using a population-averaged AIF and three patient-specific AIFs derived from pre-bolus MRI, DCE-MRI and dynamic contrast computed tomography (DC-CT) data. METHODS The four approaches were compared in 13 patients with abdominal metastases. Baseline repeatability [Bland-Altman statistics; coefficient of variation (CoV)], cohort percentage change and p value (paired t test) and number of patients with significant DCE-MRI parameter change post-treatment (limits of agreement) were assessed. RESULTS Individual AIFs were obtained for all 13 patients with pre-bolus MRI and DC-CT-derived AIFs, but only 10/13 patients had AIFs measurable from DCE-MRI data. The best CoV (7.5 %) of the transfer coefficient between blood plasma and extravascular extracellular space (K (trans)) was obtained using a population-averaged AIF. All four AIF methods detected significant treatment changes: the most significant was the DC-CT-derived AIF. The population-based AIF was similar to or better than the pre-bolus and DCE-MRI-derived AIFs. CONCLUSIONS A population-based AIF is the recommended approach for measuring cohort and individual effects since it has the best repeatability and none of the PK parameters derived using measured AIFs demonstrated an improvement in treatment sensitivity. KEY POINTS • Pharmacokinetic modelling of DCE-MRI data requires a reliable measure of AIF. • Individual MRI-DCE-derived AIFs cannot reliably be extracted from patients. • All four AIF methods detected significant K (trans) changes after treatment. • A population-based AIF can be recommended for measuring cohort treatment responses in trials.
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Affiliation(s)
- Mihaela Rata
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research and Royal Marsden Hospital, London, UK
| | - David J Collins
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research and Royal Marsden Hospital, London, UK
| | - James Darcy
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research and Royal Marsden Hospital, London, UK
| | - Christina Messiou
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research and Royal Marsden Hospital, London, UK
| | - Nina Tunariu
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research and Royal Marsden Hospital, London, UK
| | - Nandita Desouza
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research and Royal Marsden Hospital, London, UK
| | - Helen Young
- Early Clinical Development, AstraZeneca, Macclesfield, Cheshire, UK
| | - Martin O Leach
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research and Royal Marsden Hospital, London, UK.
- CRUK Cancer Imaging Centre, MRI Unit, Royal Marsden Hospital, Downs Road, Sutton, Surrey, SM2 5PT, UK.
| | - Matthew R Orton
- CR-UK Cancer Imaging Centre, Division of Radiotherapy and Imaging, Institute of Cancer Research and Royal Marsden Hospital, London, UK
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13
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Turco S, Wijkstra H, Mischi M. Mathematical Models of Contrast Transport Kinetics for Cancer Diagnostic Imaging: A Review. IEEE Rev Biomed Eng 2016; 9:121-47. [PMID: 27337725 DOI: 10.1109/rbme.2016.2583541] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Angiogenesis plays a fundamental role in cancer growth and the formation of metastasis. Novel cancer therapies aimed at inhibiting angiogenic processes and/or disrupting angiogenic tumor vasculature are currently being developed and clinically tested. The need for earlier and improved cancer diagnosis, and for early evaluation and monitoring of therapeutic response to angiogenic treatment, have led to the development of several imaging methods for in vivo noninvasive assessment of angiogenesis. The combination of dynamic contrast-enhanced imaging with mathematical modeling of the contrast agent kinetics enables quantitative assessment of the structural and functional changes in the microvasculature that are associated with tumor angiogenesis. In this paper, we review quantitative imaging of angiogenesis with dynamic contrast-enhanced magnetic resonance imaging, computed tomography, and ultrasound.
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14
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Bedair R, Graves MJ, Patterson AJ, McLean MA, Manavaki R, Wallace T, Reid S, Mendichovszky I, Griffiths J, Gilbert FJ. Effect of Radiofrequency Transmit Field Correction on Quantitative Dynamic Contrast-enhanced MR Imaging of the Breast at 3.0 T. Radiology 2016; 279:368-77. [PMID: 26579563 DOI: 10.1148/radiol.2015150920] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To investigate the effects of radiofrequency transmit field (B1(+)) correction on (a) the measured T1 relaxation times of normal breast tissue and malignant lesions and (b) the pharmacokinetically derived parameters of malignant breast lesions at 3 T. MATERIALS AND METHODS Ethics approval and informed consent were obtained. Between May 2013 and January 2014, 30 women (median age, 58 years; range, 32-83 years) with invasive ductal carcinoma of at least 10 mm were recruited to undergo dynamic contrast material-enhanced magnetic resonance (MR) imaging before surgery. B1(+) and T1 mapping sequences were performed to determine the effect of B1(+) correction on the native tissue relaxation time (T10) of fat, parenchyma, and malignant lesions in both breasts. Pharmacokinetic parameters were calculated before and after correction for B1(+) variations. Results were correlated with histologic grade by using the Kruskal-Wallis test. RESULTS Measurements showed a mean 37% flip angle difference between the right and left breast, which resulted in a 61% T10 difference in fat and a 41.5% difference in parenchyma between the two breasts. The T1 of lesions in the right breast increased by 58%, whereas that of lesions in the left breast decreased by 30% after B1(+) correction. The whole-tumor transendothelial permeability across the vascular compartment(K(trans)) of lesions in the right breast decreased by 41%, and that of lesions in the left breast increased by 46% after correction. A systematic increase in K(trans) was observed, with significant differences found across the histologic grades (P < .001). The effect size of B1(+) correction on K(trans) calculation was large for lesions in the right breast and moderate for lesions in the left breast (Cohen effect size, d = 0.86 and d = 0.59, respectively). CONCLUSION B1(+) correction demonstrates a substantial effect on the results of quantitative dynamic contrast-enhanced analysis of breast tissue at 3 T, which propagates into the pharmacokinetic analysis of tumors that is dependent on whether the tumor is located in the right or left breast.
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Affiliation(s)
- Reem Bedair
- From the Department of Radiology, School of Clinical Medicine, University of Cambridge, Box 218, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, England (R.B., M.J.G., R.M., T.W., I.M., F.J.G.); Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, England (M.J.G., A.J.P., M.A.M.); Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, England (M.A.M., J.G.); and General Electric Company, GE Medical Systems Limited, Chalfont St Giles, England (S.R.)
| | - Martin J Graves
- From the Department of Radiology, School of Clinical Medicine, University of Cambridge, Box 218, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, England (R.B., M.J.G., R.M., T.W., I.M., F.J.G.); Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, England (M.J.G., A.J.P., M.A.M.); Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, England (M.A.M., J.G.); and General Electric Company, GE Medical Systems Limited, Chalfont St Giles, England (S.R.)
| | - Andrew J Patterson
- From the Department of Radiology, School of Clinical Medicine, University of Cambridge, Box 218, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, England (R.B., M.J.G., R.M., T.W., I.M., F.J.G.); Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, England (M.J.G., A.J.P., M.A.M.); Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, England (M.A.M., J.G.); and General Electric Company, GE Medical Systems Limited, Chalfont St Giles, England (S.R.)
| | - Mary A McLean
- From the Department of Radiology, School of Clinical Medicine, University of Cambridge, Box 218, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, England (R.B., M.J.G., R.M., T.W., I.M., F.J.G.); Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, England (M.J.G., A.J.P., M.A.M.); Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, England (M.A.M., J.G.); and General Electric Company, GE Medical Systems Limited, Chalfont St Giles, England (S.R.)
| | - Roido Manavaki
- From the Department of Radiology, School of Clinical Medicine, University of Cambridge, Box 218, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, England (R.B., M.J.G., R.M., T.W., I.M., F.J.G.); Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, England (M.J.G., A.J.P., M.A.M.); Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, England (M.A.M., J.G.); and General Electric Company, GE Medical Systems Limited, Chalfont St Giles, England (S.R.)
| | - Tess Wallace
- From the Department of Radiology, School of Clinical Medicine, University of Cambridge, Box 218, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, England (R.B., M.J.G., R.M., T.W., I.M., F.J.G.); Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, England (M.J.G., A.J.P., M.A.M.); Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, England (M.A.M., J.G.); and General Electric Company, GE Medical Systems Limited, Chalfont St Giles, England (S.R.)
| | - Scott Reid
- From the Department of Radiology, School of Clinical Medicine, University of Cambridge, Box 218, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, England (R.B., M.J.G., R.M., T.W., I.M., F.J.G.); Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, England (M.J.G., A.J.P., M.A.M.); Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, England (M.A.M., J.G.); and General Electric Company, GE Medical Systems Limited, Chalfont St Giles, England (S.R.)
| | - Iosif Mendichovszky
- From the Department of Radiology, School of Clinical Medicine, University of Cambridge, Box 218, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, England (R.B., M.J.G., R.M., T.W., I.M., F.J.G.); Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, England (M.J.G., A.J.P., M.A.M.); Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, England (M.A.M., J.G.); and General Electric Company, GE Medical Systems Limited, Chalfont St Giles, England (S.R.)
| | - John Griffiths
- From the Department of Radiology, School of Clinical Medicine, University of Cambridge, Box 218, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, England (R.B., M.J.G., R.M., T.W., I.M., F.J.G.); Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, England (M.J.G., A.J.P., M.A.M.); Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, England (M.A.M., J.G.); and General Electric Company, GE Medical Systems Limited, Chalfont St Giles, England (S.R.)
| | - Fiona J Gilbert
- From the Department of Radiology, School of Clinical Medicine, University of Cambridge, Box 218, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0QQ, England (R.B., M.J.G., R.M., T.W., I.M., F.J.G.); Department of Radiology, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Hills Road, Cambridge, England (M.J.G., A.J.P., M.A.M.); Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge, England (M.A.M., J.G.); and General Electric Company, GE Medical Systems Limited, Chalfont St Giles, England (S.R.)
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15
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Sung YS, Park B, Choi Y, Lim HS, Woo DC, Kim KW, Kim JK. Dynamic contrast-enhanced MRI for oncology drug development. J Magn Reson Imaging 2016; 44:251-64. [PMID: 26854494 DOI: 10.1002/jmri.25173] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 01/15/2016] [Indexed: 12/17/2022] Open
Abstract
Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a promising tool for evaluating tumor vascularity, as it can provide vasculature-derived, functional, and quantitative parameters. To implement DCE-MRI parameters as biomarkers for monitoring the effect of antiangiogenic or vascular-disrupting treatment, two crucial elements of surrogate endpoint, ie, validation and qualification, should be satisfied. Although early studies have shown the accuracy and reliability of DCE-MRI parameters for evaluating treatment-driven vascular alterations, there have been an increasing number of studies demonstrating the limitations of DCE-MRI parameters as surrogate endpoints. Therefore, in order to improve the application of DCE-MRI parameters in drug development, it is necessary to establish a standardized evaluation method and to determine the correct therapeutics-oriented meaning of individual DCE-MRI parameter. In this regard, this article describes the biophysical background and data acquisition/analysis techniques of DCE-MRI while focusing on the validation and qualification issues. Specifically, the causes of disagreement and confusion encountered in the preclinical and clinical trials using DCE-MRI are presented in detail. Finally, considering these limitations, we present potential strategies to optimize implementation of DCE-MRI. J. Magn. Reson. Imaging 2016;44:251-264.
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Affiliation(s)
- Yu Sub Sung
- Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.,Center for Bioimaging of New Drug Development, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Bumwoo Park
- Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.,Center for Bioimaging of New Drug Development, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Yoonseok Choi
- Center for Bioimaging of New Drug Development, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Hyeong-Seok Lim
- Center for Bioimaging of New Drug Development, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.,Department of Clinical Pharmacology and Therapeutics, Ulsan University College of Medicine, Asan Medical Center, Seoul, South Korea
| | - Dong-Cheol Woo
- Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.,Center for Bioimaging of New Drug Development, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Kyung Won Kim
- Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.,Center for Bioimaging of New Drug Development, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Jeong Kon Kim
- Department of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.,Center for Bioimaging of New Drug Development, Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
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16
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Wang S, Fan X, Medved M, Pineda FD, Yousuf A, Oto A, Karczmar GS. Arterial input functions (AIFs) measured directly from arteries with low and standard doses of contrast agent, and AIFs derived from reference tissues. Magn Reson Imaging 2016; 34:197-203. [PMID: 26523650 PMCID: PMC5006387 DOI: 10.1016/j.mri.2015.10.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 10/20/2015] [Accepted: 10/25/2015] [Indexed: 02/08/2023]
Abstract
Measurements of arterial input function (AIF) can have large systematic errors at standard contrast agent doses in dynamic contrast enhanced MRI (DCE-MRI). We compared measured AIFs from low dose (AIFLD) and standard dose (AIFSD) contrast agent injections, as well as the AIF derived from a muscle reference tissue and artery (AIFref). Twenty-two prostate cancer patients underwent DCE-MRI. Data were acquired on a 3T scanner using an mDixon sequence. Gadobenate dimeglumine was injected twice, at doses of 0.015 and 0.085 mmol/kg. Directly measured AIFs were fitted with empirical mathematical models (EMMs) and compared to the AIF derived from a muscle reference tissue (AIFref). EMMs accurately fitted the AIFs. The 1st and 2nd pass peaks were visualized in AIFLD, but not in AIFSD, thus the peak and shape of AIFSD could not be accurately measured directly. The average scaling factor between AIFSD and AIFLD in the washout phase was only 56% of the contrast dose ratio (~6:1). The shape and magnitude of AIFref closely approximated that of AIFLD after empirically determined dose-dependent normalization. This suggests that AIFref may be a good approximation of the local AIF.
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Affiliation(s)
| | | | | | | | | | | | - Gregory S. Karczmar
- Corresponding author at: Department of Radiology, MC2026, University of Chicago, 5841 S. Maryland Ave., Chicago, IL, USA 60637. Tel.: +1 773 702 0214. (G.S. Karczmar)
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17
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Likhite D, Suksaranjit P, Adluru G, Hu N, Weng C, Kholmovski E, McGann C, Wilson B, DiBella E. Interstudy repeatability of self-gated quantitative myocardial perfusion MRI. J Magn Reson Imaging 2015; 43:1369-78. [PMID: 26663511 DOI: 10.1002/jmri.25107] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Accepted: 11/14/2015] [Indexed: 01/04/2023] Open
Abstract
PURPOSE To evaluate the interstudy repeatability of multislice quantitative cardiovascular magnetic resonance myocardial blood flow (MBF), myocardial perfusion reserve (MPR), and extracellular volume (ECV). A unique saturation recovery self-gated acquisition was used for the perfusion scans. MATERIALS AND METHODS An ungated golden angle radial turboFLASH pulse sequence was used to scan 10 subjects on two separate days on a 3T scanner. A single saturation pulse was followed by a set of four slices. Rest and hyperemia scans were acquired during free breathing. The images were reconstructed using an iterative algorithm with spatiotemporal constraints. The ungated images were retrospectively binned (self-gated) into near-systole and near-diastole. Deformable registration was performed to adjust for respiratory and residual cardiac motion, and the data were fit with a Fermi model to estimate the interstudy repeatability of quantitative self-gated MBF and MPR. RESULTS The coefficient of variation (CoV) of the territorial MPR using the self-gated near-systole data was 18.6%. The self-gated near-diastole data gave less good CoV of MPR, equal to 46.2%. For MBFs, and using smaller (segmental) regions, the CoVs were 20.1% and 22.7% for the estimation of myocardial blood flow at stress and rest, respectively, using the self-gated near-systole data. The self-gated near-diastole data gave CoV = 48.6% and 44.9% for stress and rest. CONCLUSION The self-gated free-breathing technique for quantification of myocardial blood flow showed good repeatability for near-systole, with results comparable to published studies on interstudy repeatability of quantitative myocardial perfusion MRI using ECG-gating and breath-holds. Self-gated near-diastole data results were less repeatable. J. Magn. Reson. Imaging 2016;43:1369-1378.
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Affiliation(s)
- Devavrat Likhite
- Utah Center for Advanced Imaging Research, Department of Radiology, University of Utah, Salt Lake City, Utah, USA
| | - Promporn Suksaranjit
- Division of Cardiovascular Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Ganesh Adluru
- Utah Center for Advanced Imaging Research, Department of Radiology, University of Utah, Salt Lake City, Utah, USA
| | - Nan Hu
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Cindy Weng
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Eugene Kholmovski
- Utah Center for Advanced Imaging Research, Department of Radiology, University of Utah, Salt Lake City, Utah, USA
| | - Chris McGann
- Division of Cardiovascular Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Brent Wilson
- Division of Cardiovascular Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Edward DiBella
- Utah Center for Advanced Imaging Research, Department of Radiology, University of Utah, Salt Lake City, Utah, USA.,Department of Bioengineering, University of Utah, Salt Lake City, Utah, USA
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Mehrabian H, Da Rosa M, Haider MA, Martel AL. Pharmacokinetic analysis of prostate cancer using independent component analysis. Magn Reson Imaging 2015; 33:1236-1245. [DOI: 10.1016/j.mri.2015.08.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 08/12/2015] [Accepted: 08/17/2015] [Indexed: 10/23/2022]
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Lai AY, Dorr A, Thomason LAM, Koletar MM, Sled JG, Stefanovic B, McLaurin J. Venular degeneration leads to vascular dysfunction in a transgenic model of Alzheimer's disease. ACTA ACUST UNITED AC 2015; 138:1046-58. [PMID: 25688079 DOI: 10.1093/brain/awv023] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Most patients with Alzheimer's disease exhibit accumulation of amyloid-β peptide on leptomeningeal and cortical arterioles, or cerebral amyloid angiopathy, which is associated with impaired vascular reactivity and accelerated cognitive decline. Despite widespread recognition of the significance of vascular dysfunction in Alzheimer's disease aetiology and progression, much uncertainty still surrounds the mechanism underlying Alzheimer's disease vascular injury. Studies to date have focused on amyloid-β-induced damage to capillaries and plaque-associated arterioles, without examining effects across the entire vascular bed. In the present study, we investigated the structural and functional impairment of the feeding arteriolar versus draining venular vessels in a transgenic murine Alzheimer's disease model, with a particular focus on the mural cell populations that dictate these vessels' contractility. Although amyloid-β deposition was restricted to arterioles, we found that vascular impairment extended to the venules, which showed significant depletion of their mural cell coverage by the mid-stage of Alzheimer's disease pathophysiology. These structural abnormalities were accompanied by an abolishment of the normal vascular network flow response to hypercapnia: this functional impairment was so severe as to result in hypercapnia-induced flow decreases in the arterioles. Further pharmacological depletion of mural cells using SU6668, a platelet-derived growth factor receptor-β antagonist, resulted in profound structural abnormalities of the cortical microvasculature, including vessel coiling and short-range looping, increased tortuosity of the venules but not of the arterioles, increased amyloid-β deposition on the arterioles, and further alterations of the microvascular network cerebral blood flow response to hypercapnia. Together, this work shows hitherto unrecognized structural alterations in penetrating venules, demonstrates their functional significance and sheds light on the complexity of the relationship between vascular network structure and function in Alzheimer's disease.
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Affiliation(s)
- Aaron Y Lai
- 1 Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada 2 Sunnybrook Research Institute, Toronto, ON, Canada
| | - Adrienne Dorr
- 2 Sunnybrook Research Institute, Toronto, ON, Canada
| | | | | | - John G Sled
- 3 Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada 4 Hospital for Sick Children, Toronto, ON, Canada
| | - Bojana Stefanovic
- 2 Sunnybrook Research Institute, Toronto, ON, Canada 3 Department of Medical Biophysics, University of Toronto, Toronto, ON, Canada
| | - JoAnne McLaurin
- 1 Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada 2 Sunnybrook Research Institute, Toronto, ON, Canada
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Likhite D, Adluru G, Hu N, McGann C, DiBella E. Quantification of myocardial perfusion with self-gated cardiovascular magnetic resonance. J Cardiovasc Magn Reson 2015; 17:14. [PMID: 25827080 PMCID: PMC4325943 DOI: 10.1186/s12968-015-0109-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 12/31/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Current myocardial perfusion measurements make use of an ECG-gated pulse sequence to track the uptake and washout of a gadolinium-based contrast agent. The use of a gated acquisition is a problem in situations with a poor ECG signal. Recently, an ungated perfusion acquisition was proposed but it is not known how accurately quantitative perfusion estimates can be made from such datasets that are acquired without any triggering signal. METHODS An undersampled saturation recovery radial turboFLASH pulse sequence was used in 7 subjects to acquire dynamic contrast-enhanced images during free-breathing. A single saturation pulse was followed by acquisition of 4-5 slices after a delay of ~40 msec. This was repeated without pause and without any type of gating. The same pulse sequence, with ECG-gating, was used to acquire gated data as a ground truth. An iterative spatio-temporal constrained reconstruction was used to reconstruct the undersampled images. After reconstruction, the ungated images were retrospectively binned ("self-gated") into two cardiac phases using a region of interest based technique and deformably registered into near-systole and near-diastole. The gated and the self-gated datasets were then quantified with standard methods. RESULTS Regional myocardial blood flow estimates (MBFs) obtained using self-gated systole (0.64 ± 0.26 ml/min/g), self-gated diastole (0.64 ± 0.26 ml/min/g), and ECG-gated scans (0.65 ± 0.28 ml/min/g) were similar. Based on the criteria for interchangeable methods listed in the statistical analysis section, the MBF values estimated from self-gated and gated methods were not significantly different. CONCLUSION The self-gated technique for quantification of regional myocardial perfusion matched ECG-gated perfusion measurements well in normal subjects at rest. Self-gated systolic perfusion values matched ECG-gated perfusion values better than did diastolic values.
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Affiliation(s)
- Devavrat Likhite
- />Department of Radiology, Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, UT USA
| | - Ganesh Adluru
- />Department of Radiology, Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, UT USA
| | - Nan Hu
- />Department of Internal Medicine, University of Utah, Salt Lake City, UT USA
| | - Chris McGann
- />Division of Cardiology, University of Utah, Salt Lake City, UT USA
| | - Edward DiBella
- />Department of Radiology, Utah Center for Advanced Imaging Research, University of Utah, Salt Lake City, UT USA
- />Department of Bioengineering, University of Utah, Salt Lake City, UT USA
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Gill AB, Black RT, Bowden DJ, Priest AN, Graves MJ, Lomas DJ. An investigation into the effects of temporal resolution on hepatic dynamic contrast-enhanced MRI in volunteers and in patients with hepatocellular carcinoma. Phys Med Biol 2014; 59:3187-200. [PMID: 24862216 DOI: 10.1088/0031-9155/59/12/3187] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This study investigated the effect of temporal resolution on the dual-input pharmacokinetic (PK) modelling of dynamic contrast-enhanced MRI (DCE-MRI) data from normal volunteer livers and from patients with hepatocellular carcinoma. Eleven volunteers and five patients were examined at 3 T. Two sections, one optimized for the vascular input functions (VIF) and one for the tissue, were imaged within a single heart-beat (HB) using a saturation-recovery fast gradient echo sequence. The data was analysed using a dual-input single-compartment PK model. The VIFs and/or uptake curves were then temporally sub-sampled (at interval ▵t = [2-20] s) before being subject to the same PK analysis. Statistical comparisons of tumour and normal tissue PK parameter values using a 5% significance level gave rise to the same study results when temporally sub-sampling the VIFs to HB < ▵t <4 s. However, sub-sampling to ▵t > 4 s did adversely affect the statistical comparisons. Temporal sub-sampling of just the liver/tumour tissue uptake curves at ▵t ≤ 20 s, whilst using high temporal resolution VIFs, did not substantially affect PK parameter statistical comparisons. In conclusion, there is no practical advantage to be gained from acquiring very high temporal resolution hepatic DCE-MRI data. Instead the high temporal resolution could be usefully traded for increased spatial resolution or SNR.
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Affiliation(s)
- Andrew B Gill
- Department of Radiology, University of Cambridge, Cambridge, UK. Department of Medical Physics, Cambridge University Hospitals, Cambridge, UK
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Aronhime S, Calcagno C, Jajamovich GH, Dyvorne HA, Robson P, Dieterich D, Fiel MI, Martel-Laferriere V, Chatterji M, Rusinek H, Taouli B. DCE-MRI of the liver: effect of linear and nonlinear conversions on hepatic perfusion quantification and reproducibility. J Magn Reson Imaging 2013; 40:90-8. [PMID: 24923476 DOI: 10.1002/jmri.24341] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Accepted: 07/12/2013] [Indexed: 12/20/2022] Open
Abstract
PURPOSE To evaluate the effect of different methods to convert magnetic resonance (MR) signal intensity (SI) to gadolinium concentration ([Gd]) on estimation and reproducibility of model-free and modeled hepatic perfusion parameters measured with dynamic contrast-enhanced (DCE)-MRI. MATERIALS AND METHODS In this Institutional Review Board (IRB)-approved prospective study, 23 DCE-MRI examinations of the liver were performed on 17 patients. SI was converted to [Gd] using linearity vs. nonlinearity assumptions (using spoiled gradient recalled echo [SPGR] signal equations). The [Gd] vs. time curves were analyzed using model-free parameters and a dual-input single compartment model. Perfusion parameters obtained with the two conversion methods were compared using paired Wilcoxon test. Test-retest and interobserver reproducibility of perfusion parameters were assessed in six patients. RESULTS There were significant differences between the two conversion methods for the following parameters: AUC60 (area under the curve at 60 s, P < 0.001), peak gadolinium concentration (Cpeak, P < 0.001), upslope (P < 0.001), Fp (portal flow, P = 0.04), total hepatic flow (Ft, P = 0.007), and MTT (mean transit time, P < 0.001). Our preliminary results showed acceptable to good reproducibility for all model-free parameters for both methods (mean coefficient of variation [CV] range, 11.87-23.7%), except for upslope (CV = 37%). Among modeled parameters, DV (distribution volume) had CV <22% with both methods, PV and MTT showed CV <21% and <29% using SPGR equations, respectively. Other modeled parameters had CV >30% with both methods. CONCLUSION Linearity assumption is acceptable for quantification of model-free hepatic perfusion parameters while the use of SPGR equations and T1 mapping may be recommended for the quantification of modeled hepatic perfusion parameters.
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Affiliation(s)
- Shimon Aronhime
- Translational and Molecular Imaging Institute and Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Calcagno C, Robson PM, Ramachandran S, Mani V, Kotys-Traughber M, Cham M, Fischer SE, Fayad ZA. SHILO, a novel dual imaging approach for simultaneous HI-/LOw temporal (Low-/Hi-spatial) resolution imaging for vascular dynamic contrast enhanced cardiovascular magnetic resonance: numerical simulations and feasibility in the carotid arteries. J Cardiovasc Magn Reson 2013; 15:42. [PMID: 23706156 PMCID: PMC3668185 DOI: 10.1186/1532-429x-15-42] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 04/23/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Dynamic contrast enhanced (DCE) cardiovascular magnetic resonance (CMR) is increasingly used to quantify microvessels and permeability in atherosclerosis. Accurate quantification depends on reliable sampling of both vessel wall (VW) uptake and contrast agent dynamic in the blood plasma (the so called arterial input function, AIF). This poses specific challenges in terms of spatial/temporal resolution and matched dynamic MR signal range, which are suboptimal in current vascular DCE-CMR protocols. In this study we describe a novel dual-imaging approach, which allows acquiring simultaneously AIF and VW images using different spatial/temporal resolution and optimizes imaging parameters for the two compartments. We refer to this new acquisition as SHILO, Simultaneous HI-/LOw-temporal (low-/hi-spatial) resolution DCE-imaging. METHODS In SHILO, the acquisition of low spatial resolution single-shot AIF images is interleaved with segments of higher spatial resolution images of the VW. This allows sampling the AIF and VW with different spatial/temporal resolution and acquisition parameters, at independent spatial locations. We show the adequacy of this temporal sampling scheme by using numerical simulations. Following, we validate the MR signal of SHILO against a standard 2D spoiled gradient recalled echo (SPGR) acquisition with in vitro and in vivo experiments. Finally, we show feasibility of using SHILO imaging in subjects with carotid atherosclerosis. RESULTS Our simulations confirmed the superiority of the SHILO temporal sampling scheme over conventional strategies that sample AIF and tissue curves at the same time resolution. Both the median relative errors and standard deviation of absolute parameter values were lower for the SHILO than for conventional sampling schemes. We showed equivalency of the SHILO signal and conventional 2D SPGR imaging, using both in vitro phantom experiments (R2 =0.99) and in vivo acquisitions (R2 =0.95). Finally, we showed feasibility of using the newly developed SHILO sequence to acquire DCE-CMR data in subjects with carotid atherosclerosis to calculate plaque perfusion indices. CONCLUSIONS We successfully demonstrate the feasibility of using the newly developed SHILO dual-imaging technique for simultaneous AIF and VW imaging in DCE-CMR of atherosclerosis. Our initial results are promising and warrant further investigation of this technique in wider studies measuring kinetic parameters of plaque neovascularization with validation against gold standard techniques.
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Affiliation(s)
- Claudia Calcagno
- Translational and Molecular Imaging Institute, Imaging Science Laboratories, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1234, New York, NY 10029, USA
- Department of Radiology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Philip M Robson
- Translational and Molecular Imaging Institute, Imaging Science Laboratories, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1234, New York, NY 10029, USA
- Department of Radiology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Sarayu Ramachandran
- Translational and Molecular Imaging Institute, Imaging Science Laboratories, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1234, New York, NY 10029, USA
- Department of Radiology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Venkatesh Mani
- Translational and Molecular Imaging Institute, Imaging Science Laboratories, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1234, New York, NY 10029, USA
- Department of Radiology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | | | - Matthew Cham
- Translational and Molecular Imaging Institute, Imaging Science Laboratories, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1234, New York, NY 10029, USA
- Department of Radiology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Stefan E Fischer
- MR Clinical Science, Philips Healthcare, 595 Miner Road, Cleveland, OH 44143, USA
| | - Zahi A Fayad
- Translational and Molecular Imaging Institute, Imaging Science Laboratories, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1234, New York, NY 10029, USA
- Department of Radiology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
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Cheng HLM, Stikov N, Ghugre NR, Wright GA. Practical medical applications of quantitative MR relaxometry. J Magn Reson Imaging 2013; 36:805-24. [PMID: 22987758 DOI: 10.1002/jmri.23718] [Citation(s) in RCA: 147] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Conventional MR images are qualitative, and their signal intensity is dependent on several complementary contrast mechanisms that are manipulated by the MR hardware and software. In the absence of a quantitative metric for absolute interpretation of pixel signal intensities, one that is independent of scanner hardware and sequences, it is difficult to perform comparisons of MR images across subjects or longitudinally in the same subject. Quantitative relaxometry isolates the contributions of individual MR contrast mechanisms (T1, T2, T2) and provides maps, which are independent of the MR protocol and have a physical interpretation often expressed in absolute units. In addition to providing an unbiased metric for comparing MR scans, quantitative relaxometry uses the relationship between MR maps and physiology to provide a noninvasive surrogate for biopsy and histology. This study provides an overview of some promising clinical applications of quantitative relaxometry, followed by a description of the methods and challenges of acquiring accurate and precise quantitative MR maps. It concludes with three case studies of quantitative relaxometry applied to studying multiple sclerosis, liver iron, and acute myocardial infarction.
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Affiliation(s)
- Hai-Ling Margaret Cheng
- Physiology and Experimental Medicine, Research Institute, The Hospital for Sick Children, Toronto, ON, Canada
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25
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Dorr A, Sahota B, Chinta LV, Brown ME, Lai AY, Ma K, Hawkes CA, McLaurin J, Stefanovic B. Amyloid-β-dependent compromise of microvascular structure and function in a model of Alzheimer’s disease. Brain 2012; 135:3039-50. [DOI: 10.1093/brain/aws243] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Robust quantification of microvascular transit times via linear dynamical systems using two-photon fluorescence microscopy data. J Cereb Blood Flow Metab 2012; 32:1718-24. [PMID: 22714047 PMCID: PMC3434637 DOI: 10.1038/jcbfm.2012.86] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Vascular transit time is an important indicator of microcirculatory health. We present a second-order-plus-dead-time (SOPDT) model for robust estimation of kinetic parameters characterizing microvascular bolus passage using two-photon fluorescence microscopy (2PFM) in anesthetized rats receiving somatosensory stimulation. This methodology enables quantification of transit time, time-to-peak, overshoot, and rate of bolus passage through the microvascular network. The overall transit time during stimulation, of 2.2 ± 0.1 seconds, was shorter (P ~ 0.0008) than that at rest (2.7 ± 0.2 seconds). When compared with conventional γ-variate modeling, the SOPDT modeling yielded better quality of fit both at rest (P<0.0001) and on activation (P<0.001).
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27
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Wirestam R. Using contrast agents to obtain maps of regional perfusion and capillary wall permeability. ACTA ACUST UNITED AC 2012. [DOI: 10.2217/iim.12.24] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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28
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A feasible high spatiotemporal resolution breast DCE-MRI protocol for clinical settings. Magn Reson Imaging 2012; 30:1257-67. [PMID: 22770687 DOI: 10.1016/j.mri.2012.04.009] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 04/07/2012] [Accepted: 04/18/2012] [Indexed: 11/23/2022]
Abstract
Three dimensional bilateral imaging is the standard for most clinical breast dynamic contrast-enhanced (DCE) MRI protocols. Because of high spatial resolution (sRes) requirement, the typical 1-2 min temporal resolution (tRes) afforded by a conventional full-k-space-sampling gradient echo (GRE) sequence precludes meaningful and accurate pharmacokinetic analysis of DCE time-course data. The commercially available, GRE-based, k-space undersampling and data sharing TWIST (time-resolved angiography with stochastic trajectories) sequence was used in this study to perform DCE-MRI exams on thirty one patients (with 36 suspicious breast lesions) before their biopsies. The TWIST DCE-MRI was immediately followed by a single-frame conventional GRE acquisition. Blinded from each other, three radiologist readers assessed agreements in multiple lesion morphology categories between the last set of TWIST DCE images and the conventional GRE images. Fleiss' κ test was used to evaluate inter-reader agreement. The TWIST DCE time-course data were subjected to quantitative pharmacokinetic analyses. With a four-channel phased-array breast coil, the TWIST sequence produced DCE images with 20 s or less tRes and ~ 1.0×1.0×1.4 mm(3) sRes. There were no significant differences in signal-to-noise (P=.45) and contrast-to-noise (P=.51) ratios between the TWIST and conventional GRE images. The agreements in morphology evaluations between the two image sets were excellent with the intra-reader agreement ranging from 79% for mass margin to 100% for mammographic density and the inter-reader κ value ranging from 0.54 (P<.0001) for lesion size to 1.00 (P<.0001) for background parenchymal enhancement. Quantitative analyses of the DCE time-course data provided higher breast cancer diagnostic accuracy (91% specificity at 100% sensitivity) than the current clinical practice of morphology and qualitative kinetics assessments. The TWIST sequence may be used in clinical settings to acquire high spatiotemporal resolution breast DCE-MRI images for both precise lesion morphology characterization and accurate pharmacokinetic analysis.
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Sadeghi-Naini A, Falou O, Hudson JM, Bailey C, Burns PN, Yaffe MJ, Stanisz GJ, Kolios MC, Czarnota GJ. Imaging innovations for cancer therapy response monitoring. ACTA ACUST UNITED AC 2012. [DOI: 10.2217/iim.12.23] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Lobatto ME, Calcagno C, Metselaar JM, Storm G, Stroes ESG, Fayad ZA, Mulder WJM. Imaging the efficacy of anti-inflammatory liposomes in a rabbit model of atherosclerosis by non-invasive imaging. Methods Enzymol 2012; 508:211-28. [PMID: 22449928 DOI: 10.1016/b978-0-12-391860-4.00011-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Nanomedicine can provide a potent alternative to current therapeutic strategies for atherosclerosis. For example, the encapsulation of anti-inflammatory drugs into liposomes improves their pharmacokinetics and biodistribution, thereby enhancing bioavailability to atherosclerotic plaques and improving therapeutic efficacy. The evaluation of this type of experimental therapeutics can greatly benefit from in vivo evaluation to assess biological changes, which can be performed by non-invasive imaging techniques, such as ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) and dynamic contrast enhanced magnetic resonance imaging (DCE-MRI). Here, we will illustrate the methods for inducing atherosclerosis in a rabbit model, the production of anti-inflammatory liposomes and monitoring of therapeutic efficacy of experimental therapeutics with the above-mentioned imaging techniques.
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Affiliation(s)
- Mark E Lobatto
- Translational and Molecular Imaging Institute, Mount Sinai School of Medicine, New York, USA
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31
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Sourbron SP, Buckley DL. Tracer kinetic modelling in MRI: estimating perfusion and capillary permeability. Phys Med Biol 2011; 57:R1-33. [PMID: 22173205 DOI: 10.1088/0031-9155/57/2/r1] [Citation(s) in RCA: 244] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The tracer-kinetic models developed in the early 1990s for dynamic contrast-enhanced MRI (DCE-MRI) have since become a standard in numerous applications. At the same time, the development of MRI hardware has led to increases in image quality and temporal resolution that reveal the limitations of the early models. This in turn has stimulated an interest in the development and application of a second generation of modelling approaches. They are designed to overcome these limitations and produce additional and more accurate information on tissue status. In particular, models of the second generation enable separate estimates of perfusion and capillary permeability rather than a single parameter K(trans) that represents a combination of the two. A variety of such models has been proposed in the literature, and development in the field has been constrained by a lack of transparency regarding terminology, notations and physiological assumptions. In this review, we provide an overview of these models in a manner that is both physically intuitive and mathematically rigourous. All are derived from common first principles, using concepts and notations from general tracer-kinetic theory. Explicit links to their historical origins are included to allow for a transfer of experience obtained in other fields (PET, SPECT, CT). A classification is presented that reveals the links between all models, and with the models of the first generation. Detailed formulae for all solutions are provided to facilitate implementation. Our aim is to encourage the application of these tools to DCE-MRI by offering researchers a clearer understanding of their assumptions and requirements.
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Affiliation(s)
- S P Sourbron
- Division of Medical Physics, University of Leeds, Leeds, West Yorkshire, UK
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32
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Koh TS, Bisdas S, Koh DM, Thng CH. Fundamentals of tracer kinetics for dynamic contrast-enhanced MRI. J Magn Reson Imaging 2011; 34:1262-76. [PMID: 21972053 DOI: 10.1002/jmri.22795] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Accepted: 07/29/2011] [Indexed: 12/11/2022] Open
Abstract
Tracer kinetic methods employed for quantitative analysis of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) share common roots with earlier tracer studies involving arterial-venous sampling and other dynamic imaging modalities. This article reviews the essential foundation concepts and principles in tracer kinetics that are relevant to DCE MRI, including the notions of impulse response and convolution, which are central to the analysis of DCE MRI data. We further examine the formulation and solutions of various compartmental models frequently used in the literature. Topics of recent interest in the processing of DCE MRI data, such as the account of water exchange and the use of reference tissue methods to obviate the measurement of an arterial input, are also discussed. Although the primary focus of this review is on the tracer models and methods for T(1) -weighted DCE MRI, some of these concepts and methods are also applicable for analysis of dynamic susceptibility contrast-enhanced MRI data.
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Affiliation(s)
- Tong San Koh
- Department of Oncologic Imaging, National Cancer Center, Singapore; Center for Quantitative Biology, Duke-NUS Graduate Medical School, Singapore; School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore.
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Winter JD, St Lawrence KS, Cheng HLM. Quantification of renal perfusion: comparison of arterial spin labeling and dynamic contrast-enhanced MRI. J Magn Reson Imaging 2011; 34:608-15. [PMID: 21761490 DOI: 10.1002/jmri.22660] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 04/29/2011] [Indexed: 01/27/2023] Open
Abstract
PURPOSE To provide the first comparison of absolute renal perfusion obtained by arterial spin labeling (ASL) and separable compartment modeling of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI). Moreover, we provide the first application of the dual bolus approach to quantitative DCE-MRI perfusion measurements in the kidney. MATERIALS AND METHODS Consecutive ASL and DCE-MRI acquisitions were performed on six rabbits on a 1.5 T MRI system. Gadolinium (Gd)-DTPA was administered in two separate injections to decouple measurement of the arterial input function and tissue uptake curves. For DCE perfusion, pixel-wise and mean cortex region-of-interest tissue curves were fit to a separable compartment model. RESULTS Absolute renal cortex perfusion estimates obtained by DCE and ASL were in close agreement: 3.28 ± 0.59 mL/g/min (ASL), 2.98 ± 0.60 mL/g/min (DCE), and 3.57 ± 0.96 mL/g/min (pixel-wise DCE). Renal medulla perfusion was 1.53 ± 0.35 mL/g/min (ASL) but was not adequately described by the separable compartment model. CONCLUSION ASL and DCE-MRI provided similar measures of absolute perfusion in the renal cortex, offering both noncontrast and contrast-based alternatives to improve current renal MRI assessment of kidney function.
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Affiliation(s)
- Jeff D Winter
- Research Institute, Diagnostic Imaging, Hospital for Sick Children, Toronto, Canada
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