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Yu C, Li Y, Xiao Y, Li Q, Lu W, Qiu J, Wang F, Li J. Characterization of posterior circulation blood perfusion in patients with different degrees of basilar artery tortuosity. Neurol Sci 2024:10.1007/s10072-024-07591-9. [PMID: 38809448 DOI: 10.1007/s10072-024-07591-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 05/07/2024] [Indexed: 05/30/2024]
Abstract
OBJECTIVE The morphology of basilar artery (BA) may affect posterior circulation blood perfusion. We aimed to investigate whether different degrees of BA tortuosity could lead to the alterations of posterior circulation perfusion. METHODS We collected 138 subjects with different BA tortuosity scores, including 32 cases of score 0, 45 cases of score 1, 43 cases of score 2, and 18 cases of score 3. A higher score represented a higher degree of BA tortuosity. Ordered logistic regression analysis was performed to investigate the risk factors for BA tortuosity. We quantitatively measured the cerebral blood flow (CBF) in eight posterior circulation brain regions using arterial spin labeling. SPSS 25.0 was used for statistical analysis. The correlation between the CBF and BA tortuosity was corrected by the Bonferroni method. The significance level was set at 0.006 (0.05/8). RESULTS Hypertension (HR: 2.39; 95%CI: 1.23-4.71; P = 0.01) and vertebral artery dominance (HR: 2.38; 95%CI: 1.10-4.67; P = 0.03) were risk factors for BA tortuosity. CBF in occipital gray matter (R = -0.383, P < 0.001), occipital white matter (R = -0.377, P < 0.001), temporal gray matter (R = -0.292, P = 0.001), temporal white matter (R = -0.297, P < 0.001), and cerebellum (R = -0.328, P < 0.001) were negatively correlated with BA tortuosity degree. No significant correlation was found between the BA tortuosity degree and CBF in hippocampus (R = -0.208, P = 0.014), thalamus (R = -0.001, P = 0.988) and brainstem (R = -0.204, P = 0.016). CONCLUSIONS BA tortuosity could affect posterior circulation blood perfusion. CBF was negatively correlated with BA tortuosity degree. The morphology of BA may serve as a biomarker for posterior circulation and the severity of posterior circulation ischemia.
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Affiliation(s)
- Chunyan Yu
- Department of Medical Imaging, Longgang Central Hospital of Shenzhen, Shenzhen, China
| | - Ye Li
- Department of CT, Zaozhuang Municipal Hospital, Zaozhuang, China
| | - Yuanyuan Xiao
- Department of Medical Imaging, The Seventh People's Hospital of Jinan, Jinan, China
| | - Qiang Li
- Department of Medical Imaging, The Second Affiliated Hospital of Shandong First Medical University, Tai'an, China
| | - Weizhao Lu
- School of Radiology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, China
| | - Jianfeng Qiu
- School of Radiology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, China
| | - Feng Wang
- Department of Medical Imaging, The Second Affiliated Hospital of Shandong First Medical University, Tai'an, China.
| | - Jinglei Li
- Department of Radiology, Taian Disabled Soldiers' Hospital of Shandong Province, Tai'an, China.
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Bane O, Seeliger E, Cox E, Stabinska J, Bechler E, Lewis S, Hickson LJ, Francis S, Sigmund E, Niendorf T. Renal MRI: From Nephron to NMR Signal. J Magn Reson Imaging 2023; 58:1660-1679. [PMID: 37243378 PMCID: PMC11025392 DOI: 10.1002/jmri.28828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/28/2023] Open
Abstract
Renal diseases pose a significant socio-economic burden on healthcare systems. The development of better diagnostics and prognostics is well-recognized as a key strategy to resolve these challenges. Central to these developments are MRI biomarkers, due to their potential for monitoring of early pathophysiological changes, renal disease progression or treatment effects. The surge in renal MRI involves major cross-domain initiatives, large clinical studies, and educational programs. In parallel with these translational efforts, the need for greater (patho)physiological specificity remains, to enable engagement with clinical nephrologists and increase the associated health impact. The ISMRM 2022 Member Initiated Symposium (MIS) on renal MRI spotlighted this issue with the goal of inspiring more solutions from the ISMRM community. This work is a summary of the MIS presentations devoted to: 1) educating imaging scientists and clinicians on renal (patho)physiology and demands from clinical nephrologists, 2) elucidating the connection of MRI parameters with renal physiology, 3) presenting the current state of leading MR surrogates in assessing renal structure and functions as well as their next generation of innovation, and 4) describing the potential of these imaging markers for providing clinically meaningful renal characterization to guide or supplement clinical decision making. We hope to continue momentum of recent years and introduce new entrants to the development process, connecting (patho)physiology with (bio)physics, and conceiving new clinical applications. We envision this process to benefit from cross-disciplinary collaboration and analogous efforts in other body organs, but also to maximally leverage the unique opportunities of renal physiology. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 2.
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Affiliation(s)
- Octavia Bane
- Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
- Icahn School of Medicine at Mount Sinai, BioMedical Engineering and Imaging Institute, New York City, New York, USA
| | - Erdmann Seeliger
- Institute of Translational Physiology, Charité-University Medicine Berlin, Berlin, Germany
| | - Eleanor Cox
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - Julia Stabinska
- F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, USA
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Eric Bechler
- Department of Diagnostic and Interventional Radiology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Sara Lewis
- Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York City, New York, USA
| | - LaTonya J Hickson
- Division of Nephrology and Hypertension, Mayo Clinic, Jacksonville, Florida, USA
| | - Sue Francis
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - Eric Sigmund
- Bernard and Irene Schwartz Center for Biomedical Imaging Center for Advanced Imaging Innovation and Research (CAI2R), New York University Langone Health, New York City, New York, USA
| | - Thoralf Niendorf
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
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Friedli I, Baid-Agrawal S, Unwin R, Morell A, Johansson L, Hockings PD. Magnetic Resonance Imaging in Clinical Trials of Diabetic Kidney Disease. J Clin Med 2023; 12:4625. [PMID: 37510740 PMCID: PMC10380287 DOI: 10.3390/jcm12144625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 06/28/2023] [Accepted: 07/04/2023] [Indexed: 07/30/2023] Open
Abstract
Chronic kidney disease (CKD) associated with diabetes mellitus (DM) (known as diabetic kidney disease, DKD) is a serious and growing healthcare problem worldwide. In DM patients, DKD is generally diagnosed based on the presence of albuminuria and a reduced glomerular filtration rate. Diagnosis rarely includes an invasive kidney biopsy, although DKD has some characteristic histological features, and kidney fibrosis and nephron loss cause disease progression that eventually ends in kidney failure. Alternative sensitive and reliable non-invasive biomarkers are needed for DKD (and CKD in general) to improve timely diagnosis and aid disease monitoring without the need for a kidney biopsy. Such biomarkers may also serve as endpoints in clinical trials of new treatments. Non-invasive magnetic resonance imaging (MRI), particularly multiparametric MRI, may achieve these goals. In this article, we review emerging data on MRI techniques and their scientific, clinical, and economic value in DKD/CKD for diagnosis, assessment of disease pathogenesis and progression, and as potential biomarkers for clinical trial use that may also increase our understanding of the efficacy and mode(s) of action of potential DKD therapeutic interventions. We also consider how multi-site MRI studies are conducted and the challenges that should be addressed to increase wider application of MRI in DKD.
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Affiliation(s)
- Iris Friedli
- Antaros Medical, BioVenture Hub, 43183 Mölndal, Sweden
| | - Seema Baid-Agrawal
- Transplant Center, Sahlgrenska University Hospital, University of Gothenburg, 41345 Gothenburg, Sweden
| | - Robert Unwin
- AstraZeneca R&D BioPharmaceuticals, Translational Science and Experimental Medicine, Early Cardiovascular, Renal & Metabolic Diseases (CVRM), Granta Park, Cambridge CB21 6GH, UK
| | - Arvid Morell
- Antaros Medical, BioVenture Hub, 43183 Mölndal, Sweden
| | | | - Paul D Hockings
- Antaros Medical, BioVenture Hub, 43183 Mölndal, Sweden
- MedTech West, Chalmers University of Technology, 41345 Gothenburg, Sweden
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Nishikawa Y, Takahashi N, Nishikawa S, Shimamoto Y, Nishimori K, Kobayashi M, Kimura H, Tsujikawa T, Kasuno K, Mori T, Kiyono Y, Okazawa H, Iwano M. Feasibility of Renal Blood Flow Measurement Using 64Cu-ATSM PET/MRI: A Quantitative PET and MRI Study. Diagnostics (Basel) 2023; 13:diagnostics13101685. [PMID: 37238171 DOI: 10.3390/diagnostics13101685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 04/26/2023] [Accepted: 05/08/2023] [Indexed: 05/28/2023] Open
Abstract
This study aimed to evaluate the renal blood flow (RBF) in patients with chronic kidney disease (CKD) using 64Cu(II)-diacetyl-bis(4-methylthiosemicarbazonate) (64Cu-ATSM) for positron emission tomography (PET)/magnetic resonance imaging (MRI). We included five healthy controls (HCs) and ten patients with CKD. The estimated glomerular filtration rate (eGFR) was calculated from the serum creatinine (cr) and cystatin C (cys) levels. The estimated RBF (eRBF) was calculated using the eGFR, hematocrit, and filtration fraction. A single dose of 64Cu-ATSM (300-400 MBq) was administered for RBF evaluation, and a 40 min dynamic PET scan was performed with simultaneous arterial spin labeling (ASL) imaging. PET-RBF images were obtained from the dynamic PET images at 3 min after injection using the image-derived input function method. The mean eRBF values calculated from various eGFR values differed significantly between the patients and HCs; both groups also differed significantly in terms of the RBF values (mL/min/100 g) measured using PET (151 ± 20 vs. 124 ± 22, p < 0.05) and ASL-MRI (172 ± 38 vs. 125 ± 30, p < 0.001). The ASL-MRI-RBF was positively correlated with the eRBFcr-cys (r = 0.858, p < 0.001). The PET-RBF was positively correlated with the eRBFcr-cys (r = 0.893, p < 0.001). The ASL-RBF was positively correlated with the PET-RBF (r = 0.849, p < 0.001). 64Cu-ATSM PET/MRI demonstrated the reliability of PET-RBF and ASL-RBF by comparing them with eRBF. This is the first study to demonstrate that 64Cu-ATSM-PET is useful for assessing the RBF and is well correlated with ASL-MRI.
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Affiliation(s)
- Yudai Nishikawa
- Department of Nephrology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Naoki Takahashi
- Department of Nephrology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Sho Nishikawa
- Department of Nephrology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Yuki Shimamoto
- Department of Nephrology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Kazuhisa Nishimori
- Department of Nephrology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Mamiko Kobayashi
- Department of Nephrology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Hideki Kimura
- Department of Nephrology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Tetsuya Tsujikawa
- Biomedical Imaging Research Center, University of Fukui, Fukui 910-1193, Japan
- Department of Radiology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Kenji Kasuno
- Department of Nephrology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
| | - Tetsuya Mori
- Biomedical Imaging Research Center, University of Fukui, Fukui 910-1193, Japan
| | - Yasushi Kiyono
- Biomedical Imaging Research Center, University of Fukui, Fukui 910-1193, Japan
| | - Hidehiko Okazawa
- Biomedical Imaging Research Center, University of Fukui, Fukui 910-1193, Japan
| | - Masayuki Iwano
- Department of Nephrology, Faculty of Medical Sciences, University of Fukui, Fukui 910-1193, Japan
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5
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Zhang K, Triphan SMF, Kurz FT, Ziener CH, Kauczor HU, Schlemmer HP, Sedlaczek O. Navigator-based slice tracking for prospective motion correction in kidney vessel architecture imaging. Magn Reson Imaging 2023; 98:26-35. [PMID: 36603781 DOI: 10.1016/j.mri.2023.01.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 01/01/2023] [Indexed: 01/04/2023]
Abstract
OBJECTIVES To apply a navigator-based slice tracking method to prospectively compensate the respiratory motion for kidney vessel architecture imaging (VAI). MATERIALS AND METHODS A dual gradient echo spin echo 2D EPI sequence was developed for kidney VAI. A single gradient-echo slice selection and projection readout at the location of the diaphragm along the inferior-superior direction was applied as a navigator. Navigator acquisition and fat suppression were inserted before each transverse imaging slice. Motion information was calculated after exclusion of the signal saturation in the navigator signal caused by imaging slices. The motion information was then directly sent back to the sequence and slice positioning was adjusted in real-time. The whole sequence was applied during a contrast agent pass-through. RESULTS VAI parametric maps show the structural heterogeneity of the renal vasculature. The respiratory motion from the navigator signal was precisely calculated and slice positioning was changed in real-time based on the motion information. The vibration amplitude of the signal intensity of the liver tissue at the liver-lung interface in the case of prospective motion correction (PMC) on is about 28% of the PMC off case. Compared to the case of PMC off, the coefficient of variation was reduced 30% of the case of PMC on. CONCLUSIONS This study demonstrates the feasibility of the motion-compensating technique in kidney VAI. The sequence may improve the evaluation of microvasculature in kidney diseases.
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Affiliation(s)
- Ke Zhang
- Department of Diagnostic & Interventional Radiology, Heidelberg University Hospital, Heidelberg, Germany; Department of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - Simon M F Triphan
- Department of Diagnostic & Interventional Radiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Felix T Kurz
- Department of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - Christian H Ziener
- Department of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - Hans-Ulrich Kauczor
- Department of Diagnostic & Interventional Radiology, Heidelberg University Hospital, Heidelberg, Germany
| | | | - Oliver Sedlaczek
- Department of Diagnostic & Interventional Radiology, Heidelberg University Hospital, Heidelberg, Germany; Department of Radiology, German Cancer Research Center, Heidelberg, Germany.
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6
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Zhang K, Triphan SMF, Ziener CH, Jende JME, Kauczor HU, Schlemmer HP, Sedlaczek O, Kurz FT. Navigator-based slice tracking for kidney pCASL using spin-echo EPI acquisition. Magn Reson Med 2023; 90:231-239. [PMID: 36806110 DOI: 10.1002/mrm.29621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 01/26/2023] [Accepted: 02/06/2023] [Indexed: 02/21/2023]
Abstract
PURPOSE To apply a navigator-based slice-tracking method to prospectively compensate respiratory motion for kidney pseudo-continuous arterial spin labeling (pCASL), using spin-echo (SE) EPI acquisition. METHODS A single gradient-echo slice selection and projection readout at the location of the diaphragm along the inferior-superior direction was applied as a navigator. Navigator acquisition and fat suppression were inserted before each transverse imaging slice of the readouts of a 2D-SE-EPI-based pCASL sequence. Motion information was calculated after exclusion of the signal saturation in the navigator signal caused by EPI excitations. The motion information was then used to directly adjust the slice positioning in real time. RESULTS The respiratory motion from the navigator signal was calculated, and slice positioning was changed in real time based on the motion information. We could show that motion compensation reduces kidney movement, and that the coefficients of variation across renal perfusion values were significantly reduced when motion correction was applied. The average reduction of coefficients of variation was approximately 20%, resulting in a more accurate and detailed structure of the respective perfusion maps. CONCLUSIONS This study demonstrates the feasibility of a navigator-based slice-tracking technique in kidney imaging with a SE-EPI readout pCASL sequence to reduce kidney motion.
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Affiliation(s)
- Ke Zhang
- Department of Diagnostic & Interventional Radiology, Heidelberg University Hospital, Heidelberg, Germany.,Division of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - Simon M F Triphan
- Department of Diagnostic & Interventional Radiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Christian H Ziener
- Division of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - Johann M E Jende
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Hans-Ulrich Kauczor
- Department of Diagnostic & Interventional Radiology, Heidelberg University Hospital, Heidelberg, Germany
| | | | - Oliver Sedlaczek
- Department of Diagnostic & Interventional Radiology, Heidelberg University Hospital, Heidelberg, Germany.,Division of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - Felix T Kurz
- Division of Radiology, German Cancer Research Center, Heidelberg, Germany.,Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany
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Mao W, Ding X, Ding Y, Cao B, Fu C, Kuehn B, Benkert T, Grimm R, Nickel D, Zhou J, Zeng M. Evaluation of interstitial fibrosis in chronic kidney disease by multiparametric functional MRI and histopathologic analysis. Eur Radiol 2022; 33:4138-4147. [PMID: 36502460 DOI: 10.1007/s00330-022-09329-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 09/27/2022] [Accepted: 11/28/2022] [Indexed: 12/14/2022]
Abstract
OBJECTIVES To investigate the diagnostic value of functional MRI to assess renal interstitial fibrosis in patients with chronic kidney disease (CKD). METHODS We prospectively recruited 80 CKD patients who underwent renal biopsies and 16 healthy volunteers to undergo multiparametric functional MRI examinations. The Oxford MEST-C classification was used to score the interstitial fibrosis. The diagnostic performance of functional MRI to discriminate interstitial fibrosis was evaluated by calculating the area under the receiver operating characteristic (ROC) curves. RESULTS IgA nephropathy (60%) accounted for the majority of pathologic type in the CKD patients. Apparent diffusion coefficient (ADC) from diffusion-weighted imaging (DWI) was correlated with interstitial fibrosis (rho = -0.73). Decreased renal blood flow (RBF) derived from arterial spin labeling (rho = -0.78) and decreased perfusion fraction (f) derived from DWI (rho = -0.70) were accompanied by increased interstitial fibrosis. The T1 value from T1 mapping correlated with interstitial fibrosis (rho = 0.67) (all p < 0.01). The areas under the ROC curve for the discrimination of ≤ 25% vs. > 25% and ≤ 50% vs. > 50% interstitial fibrosis were 0.87 (95% confidence interval, 0.78 to 0.94) and 0.93 (0.86 to 0.98) by ADC, 0.84 (0.74 to 0.91) and 0.94 (0.86 to 0.98) by f, 0.93 (0.85 to 0.98) and 0.90 (0.82 to 0.96) by RBF, and 0.91 (0.83 to 0.96) and 0.77 (0.66 to 0.85) by T1, respectively. CONCLUSIONS Functional MRI parameters were strongly correlated with the interstitial fibrosis of CKD. Therefore, it might a powerful tool to assess interstitial fibrosis of CKD noninvasively. KEY POINTS • In CKD patients, the renal cortical ADC value decreased and T1 value increased significantly compared with healthy volunteers. • Functional MRI revealed significantly decreased renal perfusion in CKD patients compared with healthy volunteers. • The renal cortical ADC, f, RBF, and T1 values were strongly correlated with the interstitial fibrosis of CKD.
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Affiliation(s)
- Wei Mao
- Department of Radiology, Zhongshan Hospital, Shanghai Institute of Medical Imaging, Fudan University, 180, Fenglin Road, Shanghai, 200032, People's Republic of China
| | - Xiaoqiang Ding
- Department of Nephrology, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai, 200032, People's Republic of China
| | - Yuqin Ding
- Department of Radiology, Zhongshan Hospital, Shanghai Institute of Medical Imaging, Fudan University, 180, Fenglin Road, Shanghai, 200032, People's Republic of China
| | - Bohong Cao
- Department of Radiology, Zhongshan Hospital, Shanghai Institute of Medical Imaging, Fudan University, 180, Fenglin Road, Shanghai, 200032, People's Republic of China
| | - Caixia Fu
- MR Applications Development, Siemens Shenzhen Magnetic Resonance Ltd, Shenzhen, China
| | - Bernd Kuehn
- MR Application Predevelopment, Siemens Healthcare GmbH, Erlangen, Germany
| | - Thomas Benkert
- MR Application Predevelopment, Siemens Healthcare GmbH, Erlangen, Germany
| | - Robert Grimm
- MR Application Predevelopment, Siemens Healthcare GmbH, Erlangen, Germany
| | - Dominik Nickel
- MR Application Predevelopment, Siemens Healthcare GmbH, Erlangen, Germany
| | - Jianjun Zhou
- Department of Radiology, Zhongshan Hospital, Shanghai Institute of Medical Imaging, Fudan University, 180, Fenglin Road, Shanghai, 200032, People's Republic of China.
- Department of Radiology, Zhongshan Hospital, Xiamen Branch, Fudan University, Xiamen, China.
| | - Mengsu Zeng
- Department of Radiology, Zhongshan Hospital, Shanghai Institute of Medical Imaging, Fudan University, 180, Fenglin Road, Shanghai, 200032, People's Republic of China.
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Liu J, Zhu J, Wang Y, Wang F, Yang H, Wang N, Chu Q, Yang Q. Arterial spin labeling of nasopharyngeal carcinoma shows early therapy response. Insights Imaging 2022; 13:114. [PMID: 35796807 PMCID: PMC9263025 DOI: 10.1186/s13244-022-01248-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 06/04/2022] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVE This study aimed to determine the value of arterial spin labeling (ASL) perfusion imaging in assessing the early efficacy of chemoradiotherapy for nasopharyngeal carcinoma (NPC). METHODS Fifty-five patients with locoregionally advanced NPC underwent conventional 3.0-T magnetic resonance imaging (MRI) and ASL before and after chemoradiotherapy (prescribed dose reached 40 Gy). Based on the response evaluation criteria for solid tumors (RECIST 1.1), the patients were divided into the partial response and stable disease groups. MRI re-examination was performed one month after chemoradiotherapy completion, and patients were divided into residual and non-residual groups. We investigated inter-group differences in ASL-based tumor blood flow (TBF) parameters (pre-treatment tumor blood flow, post-treatment tumor blood flow, and changes in tumor blood flow, i.e., Pre-TBF, Post-TBF, ΔTBF), correlation between TBF parameters and tumor atrophy rate, and value of TBF parameters in predicting sensitivity to chemoradiotherapy. RESULTS There were differences in Pre-TBF, Post-TBF, and ΔTBF between the partial response and stable disease groups (p < 0.01). There were also differences in Pre-TBF and ΔTBF between the residual and non-residual groups (p < 0.01). Pre-TBF and ΔTBF were significantly correlated with the tumor atrophy rate; the correlation coefficients were 0.677 and 0.567, respectively (p < 0.01). Pre-TBF had high diagnostic efficacies in predicting sensitivity to chemoradiotherapy and residual tumors, with areas under the curve of 0.845 and 0.831, respectively. CONCLUSION ASL permits a noninvasive approach to predicting the early efficacy of chemoradiotherapy for NPC.
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Affiliation(s)
- Jun Liu
- Department of Medical Imaging, Anqing Hospital Affiliated to Anhui Medical University, No352, Renmin Road, Yingjiang District, Anqing, 246003, Anhui, China
| | - Juan Zhu
- Department of Medical Imaging, Anqing Hospital Affiliated to Anhui Medical University, No352, Renmin Road, Yingjiang District, Anqing, 246003, Anhui, China
| | - Yaxian Wang
- Department of Medical Imaging, Anqing Hospital Affiliated to Anhui Medical University, No352, Renmin Road, Yingjiang District, Anqing, 246003, Anhui, China
| | - Fei Wang
- Department of Medical Imaging, Anqing Hospital Affiliated to Anhui Medical University, No352, Renmin Road, Yingjiang District, Anqing, 246003, Anhui, China
| | - Hualin Yang
- Department of Medical Imaging, Anqing Hospital Affiliated to Anhui Medical University, No352, Renmin Road, Yingjiang District, Anqing, 246003, Anhui, China
| | - Nan Wang
- Department of Medical Imaging, Anqing Hospital Affiliated to Anhui Medical University, No352, Renmin Road, Yingjiang District, Anqing, 246003, Anhui, China
| | - Qingyun Chu
- Department of Medical Oncology, Anqing Hospital Affiliated to Anhui Medical University, No352, Renmin Road, Yingjiang District, Anqing, 246003, Anhui, China
| | - Qing Yang
- Department of Medical Imaging, Anqing Hospital Affiliated to Anhui Medical University, No352, Renmin Road, Yingjiang District, Anqing, 246003, Anhui, China.
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Zheng T, Lai X, Lu J, Chen Q, Wei D. Three Dimensional-Arterial Spin Labeling Evaluation of Improved Cerebral Perfusion After Limb Remote Ischemic Preconditioning in a Rat Model of Focal Ischemic Stroke. Front Neuroanat 2022; 16:893953. [PMID: 35847828 PMCID: PMC9280338 DOI: 10.3389/fnana.2022.893953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 06/06/2022] [Indexed: 11/23/2022] Open
Abstract
Purpose To investigate the application value of 3D arterial spin labeling (3D-ASL) for evaluating distal limb ischemic preconditioning to improve acute ischemic stroke (AIS) perfusion. Materials and Methods A total of 40 patients with AISs treated in our hospital from January 2020 to December 2020 were recruited, and 15 healthy individuals who were examined in our hospital during the same period were included as the control group; all of these participants were scored on the National Institutes of Health Stroke Scale (NIHSS) and examined by MRI. Sequences included conventional sequences, diffusion-weighted imaging (DWI), magnetic resonance angiography (MRA), and 3D-ASL, and cerebral infarct volume and cerebral blood flow (CBF) in the area of the infarct lesion were measured. After 3 months of treatment, patients with AIS were scored on the modified Rankin Scale (mRS) and divided into good prognosis and poor prognosis groups. In total, 55 adult male Sprague–Dawley rats were divided randomly into three groups: 20 in the middle cerebral artery occlusion (MCAO) group, 20 in the MCAO + limb remote ischemic preconditioning (LRP) group, and 15 in the sham group. In total, 48 h after the procedures, conventional MRI, DWI, and 3D-ASL sequence data were collected, and 2,3,5-trphenyltetrazolium chloride monohydrate (TTC) staining and behavioral scoring were performed. CBF was recorded in the infarct lesion area and the corresponding contralateral area, and the affected/contralateral relative values (rCBF) were calculated to compare the differences in rCBF between different groups. The pathological changes in brain tissues were observed by HE staining, and the expression of vascular endothelial growth factor (VEGF) and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) in brain tissues was detected by immunofluorescence and real-time quantitative polymerase chain reaction (RT-qPCR). The protein expression of VEGF was detected by western blotting. Results Hypertension and internal carotid atherosclerosis are high-risk factors for ischemic stroke, and CBF values in the infarct area are significantly lower than those in the corresponding areas on the contralateral side. NIHSS and mRS scores and CBF values have higher specificity and sensitivity for the prognosis of patients with AIS. LRP significantly reduces the infarct area, improves behavioral deficits in rats with cerebral ischemia, reduces neurological injury and histological damage, protects vascular structures, and promotes neovascularization. In addition, 3D-ASL showed a significant increase in brain tissue perfusion in the ischemic area after LRP, and the expression of VEGF and CD31 showed a significant positive correlation with CBF values. Conclusion Three dimensional (3D) ASL can be used to evaluate LRP to improve stroke perfusion, and its protective effect may be closely related to LRP-induced vascular regeneration.
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Affiliation(s)
- Tianxiu Zheng
- Department of Radiology, Ningde Municipal Hospital Affiliated to Ningde Normal University, Ningde, China
| | - Xiaolan Lai
- Department of Hematology, Ningde Municipal Hospital Affiliated to Ningde Normal University, Ningde, China
| | - Jiaojiao Lu
- Department of Central Laboratory, Ningde Municipal Hospital Affiliated to Ningde Normal University, Ningde, China
| | - Qiuyan Chen
- Department of Radiology, Ningde Municipal Hospital Affiliated to Ningde Normal University, Ningde, China
| | - Dingtai Wei
- Department of Radiology, Ningde Municipal Hospital Affiliated to Ningde Normal University, Ningde, China
- *Correspondence: Dingtai Wei,
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10
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Ning Z, Chen S, Chen Z, Han H, Qiao H, Zhang N, Wang R, Shen R, Zhao X. Saturated multi-delay renal arterial spin labeling technique for simultaneous perfusion and T 1 quantification in kidneys. Magn Reson Med 2022; 88:1055-1067. [PMID: 35506512 DOI: 10.1002/mrm.29268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 03/22/2022] [Accepted: 03/24/2022] [Indexed: 11/06/2022]
Abstract
PURPOSE To propose a free-breathing simultaneous multi-delay arterial spin labeling (ASL) and T1 mapping technique with a stepwise kinetic model for renal assessment in a single 4-min scan at 3 T. METHODS The proposed saturated multi-delay renal arterial spin labeling (SAMURAI) sequence used flow-sensitive alternating inversion recovery (FAIR) preparation, followed by acquisition of 9 images with Look-Locker spoiled gradient recalled echo (SPGR). Pre-saturation at the imaging slice was used to achieve saturation-based T1 mapping. A 4-step 2-compartment kinetic model was proposed to characterize water transition through artery- and tissue-compartment. The impact of the Look-Locker sampling scheme on the ASL signal was corrected in this model. T1 estimation with dictionary searching method and perfusion quantification based on the proposed kinetic model fitting were conducted after groupwise registration of the acquired images. The feasibility and repeatability of SAMURAI were validated in healthy subjects (n = 11) and patients with different renal diseases (n = 4). RESULTS The proposed SAMURAI technique can provide accurate T1 map with strong correlation (R2 = 0.98) with inversion recovery spin echo (IR-SE) on phantom. SAMURAI provided equally reliable whole kidney and cortical ASL and T1 quantification results compared with multi-TI FAIR (intraclass correlation coefficient [ICC], 0.880-0.958) and IR-SPGR (ICC, 0.875-0.912), respectively. Low renal blood flow and increased T1 were detected by SAMURAI in the affected kidneys of the patients. SAMURAI had excellent scan-rescan repeatability (ICC, 0.905-0.992) and significantly reduced scan time (4 min 6 s vs. 45 min for 9 TIs) compared to multi-TI FAIR. CONCLUSION The proposed SAMURAI technique is feasible and repeatable for simultaneously quantifying T1 and perfusion of kidneys with high time-efficiency.
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Affiliation(s)
- Zihan Ning
- Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University School of Medicine, Beijing, China
| | - Shuo Chen
- Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University School of Medicine, Beijing, China.,Tsinghua University-Peking University Joint Center for Life Sciences, Beijing, China
| | - Zhensen Chen
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
| | - Hualu Han
- Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University School of Medicine, Beijing, China
| | - Huiyu Qiao
- Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University School of Medicine, Beijing, China.,Tsinghua University-Peking University Joint Center for Life Sciences, Beijing, China
| | - Nan Zhang
- Department of Radiology, Beijing Anzhen Hospital, Beijing, China
| | - Rui Wang
- Department of Radiology, Peking University First Hospital, Beijing, China
| | - Rui Shen
- Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University School of Medicine, Beijing, China
| | - Xihai Zhao
- Center for Biomedical Imaging Research, Department of Biomedical Engineering, Tsinghua University School of Medicine, Beijing, China
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11
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Copur S, Yavuz F, Sag AA, Tuttle KR, Kanbay M. Future of kidney imaging: Functional magnetic resonance imaging and kidney disease progression. Eur J Clin Invest 2022; 52:e13765. [PMID: 35267195 DOI: 10.1111/eci.13765] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 03/01/2022] [Accepted: 03/05/2022] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Chronic kidney disease (CKD) which is a common cause of death has an increasing trend, but there is no established approach for predicting CKD progression yet. Functional magnetic resonance imaging (fMRI) studies such as blood oxygenation level-dependent MRI (BOLD-MRI), diffusion-weighted MRI (DWI-MRI), diffusion-tensor MRI (DTI-MRI) and arterial spin labelling MRI (ASL-MRI) are rising methods for the assessment of kidney functions in native and transplanted kidneys as well as the estimation of CKD progression. METHODS Systematic literature review was performed through the Embase (Elsevier), Cochrane Central Register of Controlled Trials (Wiley), PubMed/Medline and Web of Science databases, and studies investigating the role of fMRI methods assessing kidney functions in native and transplanted kidneys, as well as the value of fMRI methods to predict CKD progression, were included. Working mechanisms, advantages and limitations of the fMRI modalities were reviewed, and three studies investigating the role of fMRI studies in kidney functions were analysed. RESULTS AND CONCLUSION BOLD-MRI signal was found to be inversely correlated with annual eGFR change, and DWI/ADC (apparent diffusion coefficient map) values were shown to be correlated with annual eGFR decline. fMRI methods which are currently used for other systems can be utilized to provide more detailed information about kidney functions, and doctors should be ready to interpret kidney MRIs.
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Affiliation(s)
- Sidar Copur
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Furkan Yavuz
- Department of Medicine, Koc University School of Medicine, Istanbul, Turkey
| | - Alan A Sag
- Department of Radiology, Division of Vascular and Interventional Radiology, Duke University Medical Center, Durham, North Carolina, USA
| | - Kathherine R Tuttle
- Division of Nephrology, University of Washington, Seattle, Washington, USA.,Providence Medical Research Center, Providence Health Care, Washington, District of Columbia, USA
| | - Mehmet Kanbay
- Department of Medicine, Division of Nephrology, Koc University School of Medicine, Istanbul, Turkey
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12
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Klepaczko A, Majos M, Stefańczyk L, Ejkefjord E, Lundervold A. Whole kidney and renal cortex segmentation in contrast-enhanced MRI using a joint classification and segmentation convolutional neural network. Biocybern Biomed Eng 2022. [DOI: 10.1016/j.bbe.2022.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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13
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Healthy Kidney Segmentation in the Dce-Mr Images Using a Convolutional Neural Network and Temporal Signal Characteristics. SENSORS 2021; 21:s21206714. [PMID: 34695931 PMCID: PMC8538657 DOI: 10.3390/s21206714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 09/30/2021] [Accepted: 10/04/2021] [Indexed: 11/17/2022]
Abstract
Quantification of renal perfusion based on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) requires determination of signal intensity time courses in the region of renal parenchyma. Thus, selection of voxels representing the kidney must be accomplished with special care and constitutes one of the major technical limitations which hampers wider usage of this technique as a standard clinical routine. Manual segmentation of renal compartments—even if performed by experts—is a common source of decreased repeatability and reproducibility. In this paper, we present a processing framework for the automatic kidney segmentation in DCE-MR images. The framework consists of two stages. Firstly, kidney masks are generated using a convolutional neural network. Then, mask voxels are classified to one of three regions—cortex, medulla, and pelvis–based on DCE-MRI signal intensity time courses. The proposed approach was evaluated on a cohort of 10 healthy volunteers who underwent the DCE-MRI examination. MRI scanning was repeated on two time events within a 10-day interval. For semantic segmentation task we employed a classic U-Net architecture, whereas experiments on voxel classification were performed using three alternative algorithms—support vector machines, logistic regression and extreme gradient boosting trees, among which SVM produced the most accurate results. Both segmentation and classification steps were accomplished by a series of models, each trained separately for a given subject using the data from other participants only. The mean achieved accuracy of the whole kidney segmentation was 94% in terms of IoU coefficient. Cortex, medulla and pelvis were segmented with IoU ranging from 90 to 93% depending on the tissue and body side. The results were also validated by comparing image-derived perfusion parameters with ground truth measurements of glomerular filtration rate (GFR). The repeatability of GFR calculation, as assessed by the coefficient of variation was determined at the level of 14.5 and 17.5% for the left and right kidney, respectively and it improved relative to manual segmentation. Reproduciblity, in turn, was evaluated by measuring agreement between image-derived and iohexol-based GFR values. The estimated absolute mean differences were equal to 9.4 and 12.9 mL/min/1.73 m2 for scanning sessions 1 and 2 and the proposed automated segmentation method. The result for session 2 was comparable with manual segmentation, whereas for session 1 reproducibility in the automatic pipeline was weaker.
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14
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Alhummiany BA, Shelley D, Saysell M, Olaru MA, Kühn B, Buckley DL, Bailey J, Wroe K, Coupland C, Mansfield MW, Sourbron SP, Sharma K. Bias and Precision in Magnetic Resonance Imaging-Based Estimates of Renal Blood Flow: Assessment by Triangulation. J Magn Reson Imaging 2021; 55:1241-1250. [PMID: 34397124 DOI: 10.1002/jmri.27888] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/31/2021] [Accepted: 08/03/2021] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Renal blood flow (RBF) can be measured with dynamic contrast enhanced-MRI (DCE-MRI) and arterial spin labeling (ASL). Unfortunately, individual estimates from both methods vary and reference-standard methods are not available. A potential solution is to include a third, arbitrating MRI method in the comparison. PURPOSE To compare RBF estimates between ASL, DCE, and phase contrast (PC)-MRI. STUDY TYPE Prospective. POPULATION Twenty-five patients with type-2 diabetes (36% female) and five healthy volunteers (HV, 80% female). FIELD STRENGTH/SEQUENCES A 3 T; gradient-echo 2D-DCE, pseudo-continuous ASL (pCASL) and cine 2D-PC. ASSESSMENT ASL, DCE, and PC were acquired once in all patients. ASL and PC were acquired four times in each HV. RBF was estimated and split-RBF was derived as (right kidney RBF)/total RBF. Repeatability error (RE) was calculated for each HV, RE = 1.96 × SD, where SD is the standard deviation of repeat scans. STATISTICAL TESTS Paired t-tests and one-way analysis of variance (ANOVA) were used for statistical analysis. The 95% confidence interval (CI) for difference between ASL/PC and DCE/PC was assessed using two-sample F-test for variances. Statistical significance level was P < 0.05. Influential outliers were assessed with Cook's distance (Di > 1) and results with outliers removed were presented. RESULTS In patients, the mean RBF (mL/min/1.73m2 ) was 618 ± 62 (PC), 526 ± 91 (ASL), and 569 ± 110 (DCE). Differences between measurements were not significant (P = 0.28). Intrasubject agreement was poor for RBF with limits-of-agreement (mL/min/1.73m2 ) [-687, 772] DCE-ASL, [-482, 580] PC-DCE, and [-277, 460] PC-ASL. The difference PC-ASL was significantly smaller than PC-DCE, but this was driven by a single-DCE outlier (P = 0.31, after removing outlier). The difference in split-RBF was comparatively small. In HVs, mean RE (±95% CI; mL/min/1.73 m2 ) was significantly smaller for PC (79 ± 41) than for ASL (241 ± 85). CONCLUSIONS ASL, DCE, and PC RBF show poor agreement in individual subjects but agree well on average. Triangulation with PC suggests that the accuracy of ASL and DCE is comparable. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
| | - David Shelley
- Department of Biomedical Imaging Sciences, University of Leeds, Leeds, UK.,Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | - Margaret Saysell
- Department of Biomedical Imaging Sciences, University of Leeds, Leeds, UK.,Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | | | - Bernd Kühn
- Siemens Healthcare GmbH, Erlangen, Germany
| | - David L Buckley
- Department of Biomedical Imaging Sciences, University of Leeds, Leeds, UK
| | | | - Kelly Wroe
- Leeds Teaching Hospitals NHS Trust, Leeds, UK
| | | | | | - Steven P Sourbron
- Department of Imaging, Infection, Immunity and Cardiovascular Disease, The University of Sheffield, Sheffield, UK
| | - Kanishka Sharma
- Department of Imaging, Infection, Immunity and Cardiovascular Disease, The University of Sheffield, Sheffield, UK
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15
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Zhang HM, Wen DG, Wang Y, Bao YG, Yuan Y, Chen YT, Song B. Arterial Spin Labeling MRI for Predicting Microvascular Invasion of T1 Staging Renal Clear Cell Carcinoma Preoperatively. Front Oncol 2021; 11:644975. [PMID: 34084743 PMCID: PMC8168533 DOI: 10.3389/fonc.2021.644975] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 04/09/2021] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Microvascular invasion (MVI) is a valuable factor for T1 staging renal clear cell carcinoma (ccRCC) operation strategy decision, which is confirmed histopathologically post-operation. This study aimed to prospectively evaluate the performance of arterial spin labeling (ASL) MRI for predicting MVI of T1 staging ccRCC preoperatively. METHODS 16 volunteers and 39 consecutive patients were enrolled. MRI examinations consisted of ASL (three post label delays separately) of the kidney, followed by T1 and T2-weighted imaging. Two sessions of ASL were used to evaluate the reproducibility on volunteers. Renal blood flow of renal cortex, medulla, the entire and solid part of the tumor were measured on ASL images. Conventional imaging features were extracted. MVI and WHO/ISUP classification were evaluated histopathologically. A paired t-test was used to compare the renal cortex and medulla between ASL 1 and ASL 2. The reproducibility was assessed using the intraclass correlation. Differences in mean perfusion between the entire and the solid parts of tumors with or without MVI were assessed separately using Student's t test. The diagnostic performance was assessed. Logistic regression analysis was used to indicate the independent prediction index for MVI. RESULTS The two sessions of ASL showed no significant difference between the mean cortex values of RBF. The cortical RBF measurements demonstrated good agreement. 12 ccRCCs presented with MVI histopathologically. Mean perfusion of the solid part of tumors with MVI were 536.4 ± 154.8 ml/min/100 g (PLD1), 2912.5 ± 939.3 ml/min/100 g (PLD2), 3280.3 ± 901.2 ml/min/100 g (PLD3). Mean perfusion of the solid part of tumors without MVI were 453.5 ± 87.2 ml/min/100 g (PLD1), 1043.6 ± 695.8 ml/min/100 g (PLD2), 1577.6 ± 1085.8 ml/min/100 g (PLD3). These two groups have significant difference at all the PLDs (p < 0.05). The RBF of PLD1 of the solid part of tumor perfusion showed well diagnostic performance for predicting MVI: sensitivity 75%, specificity 100%, positive predictive value 66.7%, and negative predictive value 95.7%. The maximum diameter of the tumor, ill-defined margin, and the solid part of tumor perfusion were the independent prediction index for MVI. CONCLUSION ASL MR imaging has good reproducibility for renal cortex, and good diagnostic performance for predicting MVI for ccRCC.
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Affiliation(s)
- Han-Mei Zhang
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - Da-Guang Wen
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - Yi Wang
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - Yi-Ge Bao
- Department of Urology, West China Hospital, Sichuan University, Chengdu, China
| | - Yuan Yuan
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - Yun-Tian Chen
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
| | - Bin Song
- Department of Radiology, West China Hospital, Sichuan University, Chengdu, China
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16
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Abstract
Interstitial fibrosis with tubule atrophy (IF/TA) is the response to virtually any sustained kidney injury and correlates inversely with kidney function and allograft survival. IF/TA is driven by various pathways that include hypoxia, renin-angiotensin-aldosterone system, transforming growth factor (TGF)-β signaling, cellular rejection, inflammation and others. In this review we will focus on key pathways in the progress of renal fibrosis, diagnosis and therapy of allograft fibrosis. This review discusses the role and origin of myofibroblasts as matrix producing cells and therapeutic targets in renal fibrosis with a particular focus on renal allografts. We summarize current trends to use multi-omic approaches to identify new biomarkers for IF/TA detection and to predict allograft survival. Furthermore, we review current imaging strategies that might help to identify and follow-up IF/TA complementary or as alternative to invasive biopsies. We further discuss current clinical trials and therapeutic strategies to treat kidney fibrosis.Supplemental Visual Abstract; http://links.lww.com/TP/C141.
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17
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Bones IK, Franklin SL, Harteveld AA, van Osch MJP, Schmid S, Hendrikse J, Moonen C, van Stralen M, Bos C. Exploring label dynamics of velocity-selective arterial spin labeling in the kidney. Magn Reson Med 2021; 86:131-142. [PMID: 33538350 PMCID: PMC8048977 DOI: 10.1002/mrm.28683] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/07/2020] [Accepted: 12/24/2020] [Indexed: 12/13/2022]
Abstract
Purpose Velocity‐selective arterial spin labeling (VSASL) has been proposed for renal perfusion imaging to mitigate planning challenges and effects of arterial transit time (ATT) uncertainties. In VSASL, label generation may shift in the vascular tree as a function of cutoff velocity. Here, we investigate label dynamics and especially the ATT of renal VSASL and compared it with a spatially selective pulsed arterial spin labeling technique, flow alternating inversion recovery (FAIR). Methods Arterial spin labeling data were acquired in 7 subjects, using free‐breathing dual VSASL and FAIR with five postlabeling delays: 400, 800, 1200, 2000, and 2600 ms. The VSASL measurements were acquired with cutoff velocities of 5, 10, and 15 cm/s, with anterior–posterior velocity‐encoding direction. Cortical perfusion‐weighted signal, temporal SNR, quantified renal blood flow, and arterial transit time were reported. Results In contrast to FAIR, renal VSASL already showed fairly high signal at the earliest postlabeling delays, for all cutoff velocities. The highest VSASL signal and temporal SNR was obtained with a cutoff velocity of 10 cm/s at postlabeling delay = 800 ms, which was earlier than for FAIR at 1200 ms. Fitted ATT on VSASL was ≤ 0 ms, indicating ATT insensitivity, which was shorter than for FAIR (189 ± 79 ms, P < .05). Finally, the average cortical renal blood flow measured with cutoff velocities of 5 cm/s (398 ± 84 mL/min/100 g) and 10 cm/s (472 ± 160 mL/min/100 g) were similar to renal blood flow measured with FAIR (441 ± 84 mL/min/100 g) (P > .05) with good correlations on subject level. Conclusion Velocity‐selective arterial spin labeling in the kidney reduces ATT sensitivity compared with the recommended pulsed arterial spin labeling method, as well as if cutoff velocity is increased to reduce spurious labeling due to motion. Thus, VSASL has potential as a method for time‐efficient, single‐time‐point, free‐breathing renal perfusion measurements, despite lower tSNR than FAIR.
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Affiliation(s)
- Isabell K Bones
- Center for Image Sciences, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Suzanne L Franklin
- Center for Image Sciences, University Medical Center Utrecht, Utrecht, the Netherlands.,C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Anita A Harteveld
- Center for Image Sciences, University Medical Center Utrecht, Utrecht, the Netherlands.,Department of Radiology and Nuclear Medicine, Erasmus MC University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Matthias J P van Osch
- C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Sophie Schmid
- C.J. Gorter Center for High Field MRI, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Jeroen Hendrikse
- Department of Radiology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Chrit Moonen
- Center for Image Sciences, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Marijn van Stralen
- Center for Image Sciences, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Clemens Bos
- Center for Image Sciences, University Medical Center Utrecht, Utrecht, the Netherlands
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18
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de Boer A, Pieters TT, Harteveld AA, Blankestijn PJ, Bos C, Froeling M, Goldschmeding R, Hoogduin HJM, Joles JA, Petri BJ, Verhaar MC, Leiner T, Nguyen TQ, van Zuilen AD. Validation of multiparametric MRI by histopathology after nephrectomy: a case study. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2020; 34:377-387. [PMID: 32954447 PMCID: PMC8154819 DOI: 10.1007/s10334-020-00887-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 07/23/2020] [Accepted: 09/01/2020] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Renal multiparametric MRI (mpMRI) is a promising tool to monitor renal allograft health to enable timely treatment of chronic allograft nephropathy. This study aims to validate mpMRI by whole-kidney histology following transplantectomy. MATERIALS AND METHODS A patient with kidney transplant failure underwent mpMRI prior to transplantectomy. The mpMRI included blood oxygenation level-dependent (BOLD) MRI, T1 and T2 mapping, diffusion-weighted imaging (DWI), 2D phase contrast (2DPC) and arterial spin labeling (ASL). Parenchymal mpMRI measures were compared to normative values obtained in 19 healthy controls. Differences were expressed in standard deviations (SD) of normative values. The mpMRI measures were compared qualitatively to histology. RESULTS The mpMRI showed a heterogeneous parenchyma consistent with extensive interstitial hemorrhage on histology. A global increase in T1 (+ 3.0 SD) and restricted diffusivity (- 3.6 SD) were consistent with inflammation and fibrosis. Decreased T2 (- 1.8 SD) indicated fibrosis or hemorrhage. ASL showed diminished cortical perfusion (- 2.9 SD) with patent proximal arteries. 2DPC revealed a 69% decrease in renal perfusion. Histological evaluation showed a dense inflammatory infiltrate and fibrotic changes, consistent with mpMRI results. Most interlobular arteries were obliterated while proximal arteries were patent, consistent with ASL findings. DISCUSSION mpMRI findings correlated well with histology both globally as well as locally.
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Affiliation(s)
- Anneloes de Boer
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.
| | - Tobias T Pieters
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Anita A Harteveld
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Peter J Blankestijn
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Clemens Bos
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Martijn Froeling
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Roel Goldschmeding
- Department of Pathology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Hans J M Hoogduin
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Jaap A Joles
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Bart-Jeroen Petri
- Department of Vascular Surgery, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Marianne C Verhaar
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Tim Leiner
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Tri Q Nguyen
- Department of Pathology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Arjan D van Zuilen
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
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19
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Li Y, Li X, Yu X, Lin M, Ouyang H, Xie L, Shang Y. Investigating the value of arterial spin labeling and intravoxel incoherent motion imaging on diagnosing nasopharyngeal carcinoma in T1 stage. Cancer Imaging 2020; 20:62. [PMID: 32859273 PMCID: PMC7456064 DOI: 10.1186/s40644-020-00339-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 08/17/2020] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND To investigate the diagnostic value of arterial spin labeling (ASL) and intravoxel incoherent motion (IVIM) imaging in distinguishing nasopharyngeal carcinoma (NPC) in T1 stage from healthy controls (HC). METHODS Forty-five newly diagnosed NPC patients in the T1 stage and thirty-one healthy volunteers who underwent MR examinations for both 3D pseudo-continuous ASL (pCASL) and IVIM were enrolled in this study. The Mann-Whitney test was used to compare the mean values of blood flow (BF) derived from pCASL and IVIM derived parameters, including apparent diffusion coefficient (ADC), pure molecular diffusion (D), pseudo-diffusion coefficient (D*) and perfusion fraction (f) between NPC tumor and benign nasopharyngeal mucosa of HC. Receiver Operating Characteristic (ROC) was performed to determine diagnostic cutoff and efficiency. The correlation coefficients among parameters were investigated using Spearman's test. RESULTS The NPC in the T1 stage showed higher mean BF, lower ADC, D, and f compared to benign nasopharyngeal mucosa (P < 0.001) with the area under curve of ROC of 0.742-0.996 (highest by BF). BF cutoff was set at > 36 mL/100 g/min; the corresponding sensitivity, specificity, and accuracy in differentiating NPC stage T1 from benign nasopharyngeal mucosa were 95.56% (43/45), 100% (31/31) and 97.37% (74/76), respectively. BF demonstrated moderate negative correlation with D* on HC (ρ [Spearman correlation coefficients] = - 0.426, P = 0.017). CONCLUSIONS ASL and IVIM could reflect the difference in perfusion and diffusion between tumor and benign nasopharyngeal mucosa, indicating a potential for accessing early diagnosis of NPC. Notably, BF, with a specificity of 100%, demonstrated better performance compared to IVIM in distinguishing malignant lesions from healthy tissue.
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Affiliation(s)
- Yujie Li
- Department of Diagnostic Radiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No17, Panjiayuannanli, Chaoyang District, Beijing, P.R. China, 100021
| | - Xiaolu Li
- Department of Diagnostic Radiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No17, Panjiayuannanli, Chaoyang District, Beijing, P.R. China, 100021
| | - Xiaoduo Yu
- Department of Diagnostic Radiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No17, Panjiayuannanli, Chaoyang District, Beijing, P.R. China, 100021
| | - Meng Lin
- Department of Diagnostic Radiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No17, Panjiayuannanli, Chaoyang District, Beijing, P.R. China, 100021.
| | - Han Ouyang
- Department of Diagnostic Radiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No17, Panjiayuannanli, Chaoyang District, Beijing, P.R. China, 100021
| | - Lizhi Xie
- MR Research China, GE Healthcare, Beijing, Beijing, P.R. China, 100176
| | - Yuqing Shang
- Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, CT06510, USA
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de Boer A, Harteveld AA, Stemkens B, Blankestijn PJ, Bos C, Franklin SL, Froeling M, Joles JA, Verhaar MC, van den Berg N, Hoogduin H, Leiner T. Multiparametric Renal MRI: An Intrasubject Test-Retest Repeatability Study. J Magn Reson Imaging 2020; 53:859-873. [PMID: 32297700 PMCID: PMC7891585 DOI: 10.1002/jmri.27167] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/30/2020] [Accepted: 03/31/2020] [Indexed: 12/13/2022] Open
Abstract
Background Renal multiparametric magnetic resonance imaging (MRI) is a promising tool for diagnosis, prognosis, and treatment monitoring in kidney disease. Purpose To determine intrasubject test–retest repeatability of renal MRI measurements. Study Type Prospective. Population Nineteen healthy subjects aged over 40 years. Field Strength/Sequences T1 and T2 mapping, R2* mapping or blood oxygenation level‐dependent (BOLD) MRI, diffusion tensor imaging (DTI), and intravoxel incoherent motion (IVIM) diffusion‐weighted imaging (DWI), 2D phase contrast, arterial spin labelling (ASL), dynamic contrast enhanced (DCE) MRI, and quantitative Dixon for fat quantification at 3T. Assessment Subjects were scanned twice with ~1 week between visits. Total scan time was ~1 hour. Postprocessing included motion correction, semiautomated segmentation of cortex and medulla, and fitting of the appropriate signal model. Statistical Test To assess the repeatability, a Bland–Altman analysis was performed and coefficients of variation (CoVs), repeatability coefficients, and intraclass correlation coefficients were calculated. Results CoVs for relaxometry (T1, T2, R2*/BOLD) were below 6.1%, with the lowest CoVs for T2 maps and highest for R2*/BOLD. CoVs for all diffusion analyses were below 7.2%, except for perfusion fraction (FP), with CoVs ranging from 18–24%. The CoV for renal sinus fat volume and percentage were both around 9%. Perfusion measurements were most repeatable with ASL (cortical perfusion only) and 2D phase contrast with CoVs of 10% and 13%, respectively. DCE perfusion had a CoV of 16%, while single kidney glomerular filtration rate (GFR) had a CoV of 13%. Repeatability coefficients (RCs) ranged from 7.7–87% (lowest/highest values for medullary mean diffusivity and cortical FP, respectively) and intraclass correlation coefficients (ICCs) ranged from −0.01 to 0.98 (lowest/highest values for cortical FP and renal sinus fat volume, respectively). Data Conclusion CoVs of most MRI measures of renal function and structure (with the exception of FP and perfusion as measured by DCE) were below 13%, which is comparable to standard clinical tests in nephrology. Level of Evidence 2 Technical Efficacy Stage 1
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Affiliation(s)
- Anneloes de Boer
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Anita A Harteveld
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Bjorn Stemkens
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Peter J Blankestijn
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Clemens Bos
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Suzanne L Franklin
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.,Department of Radiology, C.J. Gorter Center for High Field MRI, Leiden University Medical Center, Leiden, The Netherlands
| | - Martijn Froeling
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Jaap A Joles
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Marianne C Verhaar
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Nico van den Berg
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Hans Hoogduin
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Tim Leiner
- Department of Radiology, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
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Greer JS, Wang X, Wang Y, Pinho MC, Maldjian JA, Pedrosa I, Madhuranthakam AJ. Robust pCASL perfusion imaging using a 3D Cartesian acquisition with spiral profile reordering (CASPR). Magn Reson Med 2019; 82:1713-1724. [PMID: 31231894 PMCID: PMC6743738 DOI: 10.1002/mrm.27862] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 05/22/2019] [Accepted: 05/23/2019] [Indexed: 12/15/2022]
Abstract
PURPOSE To improve the robustness of arterial spin-labeled measured perfusion using a novel Cartesian acquisition with spiral profile reordering (CASPR) 3D turbo spin echo (TSE) in the brain and kidneys. METHODS The CASPR view ordering followed a pseudo-spiral trajectory on a Cartesian grid, by sampling the center of k-space at the beginning of each echo train of a segmented 3D TSE acquisition. With institutional review board approval and written informed consent, 14 normal subjects (9 brain and 5 kidneys) were scanned with pCASL perfusion imaging using 3D CASPR and compared against 3D linear TSE (brain and kidneys), the established 2D EPI and 3D gradient and spin echo perfusion (brain), and 2D single-shot turbo spin-echo perfusion (kidneys). The SNR and the quantitative perfusion values were compared among different acquisitions. RESULTS 3D CASPR TSE achieved robust perfusion across all slices compared to 3D linear TSE in the brain and kidneys. Compared to 2D EPI, 3D CASPR TSE showed higher SNR across the brain (P < 0.01), and exhibited good agreement (36.4 ± 4.7 and 36.9 ± 5.3 mL/100 g/min with 2D EPI and 3D CASPR, respectively), and with 3D gradient and spin echo (27.9 ± 7.2 mL/100 g/min). Compared to a single slice 2D single-shot turbo spin-echo acquisition, 3D CASPR TSE achieved robust perfusion across the entire kidneys in similar scan time with comparable quantified perfusion values (154.1 ± 74.6 and 151.7 ± 70.6 mL/100 g/min with 2D single-shot turbo spin-echo and 3D CASPR, respectively). CONCLUSION The CASPR view ordering with 3D TSE achieves robust arterial spin-labeled perfusion in the brain and kidneys because of the sampling of the center of k-space at the beginning of each echo train.
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Affiliation(s)
- Joshua S. Greer
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX
| | - Xinzeng Wang
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX
| | - Yiming Wang
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX
| | - Marco C. Pinho
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX
- Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX
| | - Joseph A. Maldjian
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX
- Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX
| | - Ivan Pedrosa
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX
- Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX
| | - Ananth J. Madhuranthakam
- Department of Radiology, UT Southwestern Medical Center, Dallas, TX
- Advanced Imaging Research Center, UT Southwestern Medical Center, Dallas, TX
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Zöllner FG, Šerifović-Trbalić A, Kabelitz G, Kociński M, Materka A, Rogelj P. Image registration in dynamic renal MRI-current status and prospects. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2019; 33:33-48. [PMID: 31598799 PMCID: PMC7210245 DOI: 10.1007/s10334-019-00782-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 09/16/2019] [Accepted: 09/25/2019] [Indexed: 12/26/2022]
Abstract
Magnetic resonance imaging (MRI) modalities have achieved an increasingly important role in the clinical work-up of chronic kidney diseases (CKD). This comprises among others assessment of hemodynamic parameters by arterial spin labeling (ASL) or dynamic contrast-enhanced (DCE-) MRI. Especially in the latter, images or volumes of the kidney are acquired over time for up to several minutes. Therefore, they are hampered by motion, e.g., by pulsation, peristaltic, or breathing motion. This motion can hinder subsequent image analysis to estimate hemodynamic parameters like renal blood flow or glomerular filtration rate (GFR). To overcome motion artifacts in time-resolved renal MRI, a wide range of strategies have been proposed. Renal image registration approaches could be grouped into (1) image acquisition techniques, (2) post-processing methods, or (3) a combination of image acquisition and post-processing approaches. Despite decades of progress, the translation in clinical practice is still missing. The aim of the present article is to discuss the existing literature on renal image registration techniques and show today’s limitations of the proposed techniques that hinder clinical translation. This paper includes transformation, criterion function, and search types as traditional components and emerging registration technologies based on deep learning. The current trend points towards faster registrations and more accurate results. However, a standardized evaluation of image registration in renal MRI is still missing.
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Affiliation(s)
- Frank G Zöllner
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany.
| | | | - Gordian Kabelitz
- Computer Assisted Clinical Medicine, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany
| | - Marek Kociński
- Institute of Electronics, Lodz University of Technology, Lodz, Poland
| | - Andrzej Materka
- Institute of Electronics, Lodz University of Technology, Lodz, Poland
| | - Peter Rogelj
- Faculty of Mathematics, Natural Sciences and Information Technologies, University of Primorska, Koper, Slovenia
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Haddock B, Larsson HBW, Francis S, Andersen UB. Human renal response to furosemide: Simultaneous oxygenation and perfusion measurements in cortex and medulla. Acta Physiol (Oxf) 2019; 227:e13292. [PMID: 31046189 PMCID: PMC6767552 DOI: 10.1111/apha.13292] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 04/27/2019] [Accepted: 04/29/2019] [Indexed: 12/11/2022]
Abstract
Aim Disturbances of renal medullary perfusion and metabolism have been implicated in the pathogenesis of kidney disease and hypertension. Furosemide, a loop diuretic, is widely used to prevent renal medullary hypoxia in acute kidney disease by uncoupling sodium metabolism, but its effects on medullary perfusion in humans are unknown. We performed quantitative imaging of both renal perfusion and oxygenation using Magnetic Resonance Imaging (MRI) before and during furosemide. Based on the literature, we hypothesized that furosemide would increase medullary oxygenation, decrease medullary perfusion, but cause minor changes (<10%) in renal artery flow (RAF). Methods Interleaved measurements of RAF, oxygenation (T2*) and perfusion by arterial spin labelling in the renal cortex and medulla of 9 healthy subjects were acquired before and after an injection of 20 mg furosemide. They were preceded by measurements made during isometric exercise (5 minutes handgrip bouts), which are known to induce changes in renal hemodynamics, that served as a control for the sensitivity of the hemodynamic MRI measurements. Experiments were repeated on a second day to establish that the measurements and the induced changes were reproducible. Results After furosemide, T2* values in the medulla increased by 53% (P < 0.01) while RAF and perfusion remained constant. After hand‐grip exercise, T2* values in renal medulla increased by 22% ± 9% despite a drop in medullary perfusion of 7.2% ± 4.7% and a decrease in renal arterial flow of 17.5% ± 1.7% (P < 0.05). Mean coefficients of variation between repeated measurements for all parameters were 7%. Conclusion Furosemide induced the anticipated increase in renal medullary oxygenation, attributable exclusively to a decrease in renal oxygen consumption, since no change of RAF, cortical or medullary perfusion could be demonstrated. All measures and the induced changes were reproducible.
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Affiliation(s)
- Bryan Haddock
- Department of Clinical Physiology, Nuclear Medicine & PET Rigshospitalet, Copenhagen University Hospital Glostrup Denmark
| | - Henrik B. W. Larsson
- Department of Clinical Physiology, Nuclear Medicine & PET Rigshospitalet, Copenhagen University Hospital Glostrup Denmark
| | - Susan Francis
- Sir Peter Mansfield Magnetic Resonance Centre School of Physics and Astronomy University of Nottingham Nottingham UK
| | - Ulrik B. Andersen
- Department of Clinical Physiology, Nuclear Medicine & PET Rigshospitalet, Copenhagen University Hospital Glostrup Denmark
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Wang W, Yu Y, Wen J, Zhang M, Chen J, Cheng D, Zhang L, Liu Z. Combination of Functional Magnetic Resonance Imaging and Histopathologic Analysis to Evaluate Interstitial Fibrosis in Kidney Allografts. Clin J Am Soc Nephrol 2019; 14:1372-1380. [PMID: 31416890 PMCID: PMC6730521 DOI: 10.2215/cjn.00020119] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 07/11/2019] [Indexed: 12/26/2022]
Abstract
BACKGROUND AND OBJECTIVES Recent developments indicated that functional magnetic resonance imaging (MRI) could potentially provide noninvasive assessment of kidney interstitial fibrosis in patients with kidney diseases, but direct evidence from histopathology is scarce. We aimed to explore the diagnostic utilities of functional MRI for the evaluation of kidney allograft interstitial fibrosis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We prospectively examined 103 kidney transplant recipients who underwent for-cause biopsies and 20 biopsy-proven normal subjects with functional MRI. Histomorphometric analyses of interstitial fibrosis and peritubular capillary densities were performed on digitally scanned Masson's trichrome- and CD34-stained slides, respectively. The performances of functional MRI to discriminate interstitial fibrosis were assessed by calculating the area under the curve using receiver-operating characteristic curve. RESULTS Main pathologic findings in this single-center cohort were representative of common diagnostic entities in the kidney allografts, with rejection (32%) and glomerulonephritides (31%) accounting for the majority of diagnoses. Apparent diffusion coefficient from diffusion-weighted imaging correlated with interstitial fibrosis (ρ=-0.77; P<0.001). Additionally, decreased arterial spin labelings were accompanied by peritubular capillary density reductions (r=0.77; P<0.001). Blood oxygen level-dependent (BOLD) imaging demonstrated cortical hypoxia with increasing interstitial fibrosis (ρ=0.61; P<0.001). The area under the curve for the discrimination of ≤25% versus >25% interstitial fibrosis and ≤50% versus >50% interstitial fibrosis were 0.87 (95% confidence interval [95% CI], 0.79 to 0.93) and 0.88 (95% CI, 0.80 to 0.93) by apparent diffusion coefficient, 0.92 (95% CI, 0.85 to 0.97) and 0.94 (95% CI, 0.87 to 0.98) by arterial spin labeling, 0.81 (95% CI, 0.72 to 0.88) and 0.86 (95% CI, 0.78 to 0.92) by perfusion fraction, 0.79 (95% CI, 0.69 to 0.87) and 0.85 (95% CI, 0.76 to 0.92) by BOLD imaging, respectively. CONCLUSIONS Functional MRI measurements were strongly correlated with kidney allograft interstitial fibrosis. The performances of functional MRI for discriminating ≤50% versus >50% interstitial fibrosis were good to excellent.
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Affiliation(s)
- Wei Wang
- National Clinical Research Center of Kidney Diseases, Jinling Clinical Medical College of Nanjing Medical University, Nanjing, China
| | - Yuanmeng Yu
- Department of Medical Imaging, Jinling Hospital, Clinical School of Southern Medical University, Nanjing, China
| | - Jiqiu Wen
- National Clinical Research Center of Kidney Diseases, Nanjing University School of Medicine, Nanjing, China; and
| | - Mingchao Zhang
- National Clinical Research Center of Kidney Diseases, Nanjing University School of Medicine, Nanjing, China; and
| | - Jinsong Chen
- National Clinical Research Center of Kidney Diseases, Nanjing University School of Medicine, Nanjing, China; and
| | - Dongrui Cheng
- National Clinical Research Center of Kidney Diseases, Nanjing University School of Medicine, Nanjing, China; and
| | - Longjiang Zhang
- Department of Medical Imaging, Jinling Hospital, Clinical School of Southern Medical University, Nanjing, China; .,Department of Medical Imaging, Jinling Hospital, Medical School of Nanjing University, Nanjing, China
| | - Zhihong Liu
- National Clinical Research Center of Kidney Diseases, Jinling Clinical Medical College of Nanjing Medical University, Nanjing, China; .,National Clinical Research Center of Kidney Diseases, Nanjing University School of Medicine, Nanjing, China; and
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25
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Ludwig KD, Fain SB, Nguyen SM, Golos TG, Reeder SB, Bird IM, Shah DM, Wieben OE, Johnson KM. Perfusion of the placenta assessed using arterial spin labeling and ferumoxytol dynamic contrast enhanced magnetic resonance imaging in the rhesus macaque. Magn Reson Med 2019; 81:1964-1978. [PMID: 30357902 PMCID: PMC6715150 DOI: 10.1002/mrm.27548] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 08/29/2018] [Accepted: 09/03/2018] [Indexed: 01/01/2023]
Abstract
PURPOSE To investigate the correspondence between arterial spin labeling (ASL) flow-sensitive alternating inversion recovery (FAIR) and ferumoxytol DCE MRI for the assessment of placental intervillous perfusion. METHODS Ten pregnant macaques in late second trimester were imaged at 3 T using a 2D ASL FAIR, with and without outer-volume saturation pulses used to control the bolus width, and a 3D ferumoxytol DCE-MRI acquisition. The ASL tagged/control pairs were averaged, subtracted, and normalized to create perfusion ratio maps. Contrast arrival time and uptake slope were estimated by fitting the DCE data to a sigmoid function. Macaques (N = 4) received interleukin-1β to induce inflammation and disrupt perfusion. RESULTS The FAIR tag modification with outer-volume saturation reduced the median ASL ratio percentage compared with conventional FAIR (0.64% ± 1.42% versus 0.71% ± 2.00%; P < .05). Extended ferumoxytol arrival times (34 ± 25 seconds) were observed across the placenta. No significant DCE signal change was measured in fetal tissue ( - 0.6% ± 3.0%; P = .52) or amniotic fluid (1.9% ± 8.8%; P = .59). High ASL ratio was significantly correlated with early arrival time and high uptake slope (P < .05), but ASL signal was not above noise in late-DCE-enhancing regions. No significant differences were observed in perfusion measurements between the interleukin-1β and controls (P > .05). CONCLUSION The ASL-FAIR and ferumoxytol DCE-MRI methods are feasible to detect early blood delivery to the macaque placenta. Outer volume saturation reduced the high macrovascular ASL signal. Interleukin-1β exposure did not alter placental intervillous perfusion. An endogenous-labeling perfusion technique is limited due to extended transit times for flow within the placenta beyond the immediate vicinity of the maternal spiral arteries.
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Affiliation(s)
- Kai D. Ludwig
- Medical Physics, University of Wisconsin, 1111 Highland Ave, Madison, Madison, WI, USA 53705
| | - Sean B. Fain
- Medical Physics, University of Wisconsin, 1111 Highland Ave, Madison, Madison, WI, USA 53705
- Radiology, University of Wisconsin, 600 Highland Ave, Madison, Madison, WI, USA 53792
- Biomedical Engineering, University of Wisconsin, 1415 Engineering Dr, Madison, Madison, WI, USA 53706
| | - Sydney M. Nguyen
- Wisconsin National Primate Research Center, 1220 Capitol Court, Madison, WI, USA 53715
- Obstetrics and Gynecology, University of Wisconsin, 600 Highland Ave, Madison, WI, USA 53792
| | - Thaddeus G. Golos
- Wisconsin National Primate Research Center, 1220 Capitol Court, Madison, WI, USA 53715
- Obstetrics and Gynecology, University of Wisconsin, 600 Highland Ave, Madison, WI, USA 53792
- Comparative Biosciences, University of Wisconsin, 2015 Linden Dr, Madison, Madison, WI, USA 53706
| | - Scott B. Reeder
- Medical Physics, University of Wisconsin, 1111 Highland Ave, Madison, Madison, WI, USA 53705
- Radiology, University of Wisconsin, 600 Highland Ave, Madison, Madison, WI, USA 53792
- Biomedical Engineering, University of Wisconsin, 1415 Engineering Dr, Madison, Madison, WI, USA 53706
- Medicine, University of Wisconsin, 600 Highland Ave, Madison, Madison, WI, USA 53792
- Emergency Medicine, University of Wisconsin, 600 Highland Ave, Madison, Madison, WI, USA 53792
| | - Ian M. Bird
- Obstetrics and Gynecology, University of Wisconsin, 600 Highland Ave, Madison, WI, USA 53792
| | - Dinesh M. Shah
- Obstetrics and Gynecology, University of Wisconsin, 600 Highland Ave, Madison, WI, USA 53792
| | - Oliver E. Wieben
- Medical Physics, University of Wisconsin, 1111 Highland Ave, Madison, Madison, WI, USA 53705
- Radiology, University of Wisconsin, 600 Highland Ave, Madison, Madison, WI, USA 53792
| | - Kevin M. Johnson
- Medical Physics, University of Wisconsin, 1111 Highland Ave, Madison, Madison, WI, USA 53705
- Radiology, University of Wisconsin, 600 Highland Ave, Madison, Madison, WI, USA 53792
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Nery F, De Vita E, Clark CA, Gordon I, Thomas DL. Robust kidney perfusion mapping in pediatric chronic kidney disease using single-shot 3D-GRASE ASL with optimized retrospective motion correction. Magn Reson Med 2018; 81:2972-2984. [PMID: 30536817 DOI: 10.1002/mrm.27614] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 10/24/2018] [Accepted: 10/25/2018] [Indexed: 12/18/2022]
Abstract
PURPOSE To develop a robust renal arterial spin labeling (ASL) acquisition and processing strategy for mapping renal blood flow (RBF) in a pediatric cohort with severe kidney disease. METHODS A single-shot background-suppressed 3D gradient and spin-echo (GRASE) flow-sensitive alternating inversion recovery (FAIR) ASL acquisition method was used to perform 2 studies. First, an evaluation of the feasibility of single-shot 3D-GRASE and retrospective noise reduction methods was performed in healthy volunteers. Second, a pediatric cohort with severe chronic kidney disease underwent single-shot 3D-GRASE FAIR ASL and RBF was quantified following several retrospective motion correction pipelines, including image registration and threshold-free weighted averaging. The effect of motion correction on the fit errors of saturation recovery (SR) images (required for RBF quantification) and on the perfusion-weighted image (PWI) temporal signal-to-noise ratio (tSNR) was evaluated, as well as the intra- and inter-session repeatability of renal longitudinal relaxation time (T1 ) and RBF. RESULTS The mean cortical and/or functional renal parenchyma RBF in healthy volunteers and CKD patients was 295 ± 97 and 95 ± 47 mL/100 g/min, respectively. Motion-correction reduced image artefacts in both T1 and RBF maps, significantly reduced SR fit errors, significantly increased the PWI tSNR and improved the improved the repeatability of T1 and RBF in the pediatric patient cohort. CONCLUSION Single-shot 3D-GRASE ASL combined with retrospective motion correction enabled repeatable non-invasive RBF mapping in the first pediatric cohort with severe kidney disease undergoing ASL scans.
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Affiliation(s)
- Fabio Nery
- Developmental Imaging and Biophysics Section, University College London Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Enrico De Vita
- Department of Biomedical Engineering, School of Biomedical Engineering & Imaging Sciences, King's College London, King's Health Partners, St Thomas' Hospital, London, United Kingdom
| | - Chris A Clark
- Developmental Imaging and Biophysics Section, University College London Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Isky Gordon
- Developmental Imaging and Biophysics Section, University College London Great Ormond Street Institute of Child Health, London, United Kingdom
| | - David L Thomas
- Department of Brain Repair and Rehabilitation, University College London Queen Square Institute of Neurology, Queen Square, London, United Kingdom.,Leonard Wolfson Experimental Neurology Centre, University College London Queen Square Institute of Neurology, Queen Square, London, United Kingdom
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Odudu A, Nery F, Harteveld AA, Evans RG, Pendse D, Buchanan CE, Francis ST, Fernández-Seara MA. Arterial spin labelling MRI to measure renal perfusion: a systematic review and statement paper. Nephrol Dial Transplant 2018; 33:ii15-ii21. [PMID: 30137581 PMCID: PMC6106644 DOI: 10.1093/ndt/gfy180] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 05/15/2018] [Indexed: 01/03/2023] Open
Abstract
Renal perfusion provides the driving pressure for glomerular filtration and delivers the oxygen and nutrients to fuel solute reabsorption. Renal ischaemia is a major mechanism in acute kidney injury and may promote the progression of chronic kidney disease. Thus, quantifying renal tissue perfusion is critically important for both clinicians and physiologists. Current reference techniques for assessing renal tissue perfusion have significant limitations. Arterial spin labelling (ASL) is a magnetic resonance imaging (MRI) technique that uses magnetic labelling of water in arterial blood as an endogenous tracer to generate maps of absolute regional perfusion without requiring exogenous contrast. The technique holds enormous potential for clinical use but remains restricted to research settings. This statement paper from the PARENCHIMA network briefly outlines the ASL technique and reviews renal perfusion data in 53 studies published in English through January 2018. Renal perfusion by ASL has been validated against reference methods and has good reproducibility. Renal perfusion by ASL reduces with age and excretory function. Technical advancements mean that a renal ASL study can acquire a whole kidney perfusion measurement in less than 5-10 min. The short acquisition time permits combination with other MRI techniques that might inform drug mechanisms and renal physiology. The flexibility of renal ASL has yielded several variants of the technique, but there are limited data comparing these approaches. We make recommendations for acquiring and reporting renal ASL data and outline the knowledge gaps that future research should address.
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Affiliation(s)
- Aghogho Odudu
- Division of Cardiovascular Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Fabio Nery
- Developmental Imaging & Biophysics Section, University College London, Great Ormond Street Institute of Child Health, London, UK
| | - Anita A Harteveld
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Roger G Evans
- Department of Physiology, Cardiovascular Disease Program, Biomedicine Discovery Institute, Monash University, Melbourne, Victoria, Australia
| | - Douglas Pendse
- Centre for Medical Imaging, University College London, London, UK
| | - Charlotte E Buchanan
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
| | - Susan T Francis
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK
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Zhou JY, Wang YC, Zeng CH, Ju SH. Renal Functional MRI and Its Application. J Magn Reson Imaging 2018; 48:863-881. [PMID: 30102436 DOI: 10.1002/jmri.26180] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/10/2018] [Indexed: 12/11/2022] Open
Abstract
Renal function varies according to the nature and stage of diseases. Renal functional magnetic resonance imaging (fMRI), a technique considered superior to the most common method used to estimate the glomerular filtration rate, allows for noninvasive, accurate measurements of renal structures and functions in both animals and humans. It has become increasingly prevalent in research and clinical applications. In recent years, renal fMRI has developed rapidly with progress in MRI hardware and emerging postprocessing algorithms. Function-related imaging markers can be acquired via renal fMRI, encompassing water molecular diffusion, perfusion, and oxygenation. This review focuses on the progression and challenges of the main renal fMRI methods, including dynamic contrast-enhanced MRI, blood oxygen level-dependent MRI, diffusion-weighted imaging, diffusion tensor imaging, arterial spin labeling, fat fraction imaging, and their recent clinical applications. LEVEL OF EVIDENCE 5 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:863-881.
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Affiliation(s)
- Jia-Ying Zhou
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, China
| | - Yuan-Cheng Wang
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, China
| | - Chu-Hui Zeng
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, China
| | - Sheng-Hong Ju
- Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing, China
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Shirvani S, Tokarczuk P, Statton B, Quinlan M, Berry A, Tomlinson J, Weale P, Kühn B, O'Regan DP. Motion-corrected multiparametric renal arterial spin labelling at 3 T: reproducibility and effect of vasodilator challenge. Eur Radiol 2018; 29:232-240. [PMID: 29992384 PMCID: PMC6291439 DOI: 10.1007/s00330-018-5628-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 06/14/2018] [Accepted: 06/22/2018] [Indexed: 02/02/2023]
Abstract
OBJECTIVES We investigated the feasibility and reproducibility of free-breathing motion-corrected multiple inversion time (multi-TI) pulsed renal arterial spin labelling (PASL), with general kinetic model parametric mapping, to simultaneously quantify renal perfusion (RBF), bolus arrival time (BAT) and tissue T1. METHODS In a study approved by the Health Research Authority, 12 healthy volunteers (mean age, 27.6 ± 18.5 years; 5 male) gave informed consent for renal imaging at 3 T using multi-TI ASL and conventional single-TI ASL. Glyceryl trinitrate (GTN) was used as a vasodilator challenge in six subjects. Flow-sensitive alternating inversion recovery (FAIR) preparation was used with background suppression and 3D-GRASE (gradient and spin echo) read-out, and images were motion-corrected. Parametric maps of RBF, BAT and T1 were derived for both kidneys. Agreement was assessed using Pearson correlation and Bland-Altman plots. RESULTS Inter-study correlation of whole-kidney RBF was good for both single-TI (r2 = 0.90), and multi-TI ASL (r2 = 0.92). Single-TI ASL gave a higher estimate of whole-kidney RBF compared to multi-TI ASL (mean bias, 29.3 ml/min/100 g; p <0.001). Using multi-TI ASL, the median T1 of renal cortex was shorter than that of medulla (799.6 ms vs 807.1 ms, p = 0.01), and mean whole-kidney BAT was 269.7 ± 56.5 ms. GTN had an effect on systolic blood pressure (p < 0.05) but the change in RBF was not significant. CONCLUSIONS Free-breathing multi-TI renal ASL is feasible and reproducible at 3 T, providing simultaneous measurement of renal perfusion, haemodynamic parameters and tissue characteristics at baseline and during pharmacological challenge. KEY POINTS • Multiple inversion time arterial spin labelling (ASL) of the kidneys is feasible and reproducible at 3 T. • This approach allows simultaneous mapping of renal perfusion, bolus arrival time and tissue T 1 during free breathing. • This technique enables repeated measures of renal haemodynamic characteristics during pharmacological challenge.
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Affiliation(s)
- Saba Shirvani
- Medical Research Council (MRC), London Institute of Medical Sciences (LMS), Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK
- Department of Chemistry, Imperial College London, South Kensington Campus, Exhibition Road, London, UK
| | - Paweł Tokarczuk
- Medical Research Council (MRC), London Institute of Medical Sciences (LMS), Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK
| | - Ben Statton
- Medical Research Council (MRC), London Institute of Medical Sciences (LMS), Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK
| | - Marina Quinlan
- Medical Research Council (MRC), London Institute of Medical Sciences (LMS), Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK
| | - Alaine Berry
- Medical Research Council (MRC), London Institute of Medical Sciences (LMS), Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK
| | - James Tomlinson
- Medical Research Council (MRC), London Institute of Medical Sciences (LMS), Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK
| | | | - Bernd Kühn
- Siemens Healthcare GmbH, Erlangen, Germany
| | - Declan P O'Regan
- Medical Research Council (MRC), London Institute of Medical Sciences (LMS), Imperial College London, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK.
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Evaluation of 2D Imaging Schemes for Pulsed Arterial Spin Labeling of the Human Kidney Cortex. Diagnostics (Basel) 2018; 8:diagnostics8030043. [PMID: 29958409 PMCID: PMC6165477 DOI: 10.3390/diagnostics8030043] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 06/18/2018] [Accepted: 06/25/2018] [Indexed: 01/13/2023] Open
Abstract
A number of imaging readout schemes are proposed for renal arterial spin labeling (ASL) to quantify kidney cortex perfusion, including gradient echo-based methods of balanced fast field echo (bFFE) and gradient-echo echo-planar imaging (GE-EPI), or spin echo-based schemes of spin-echo echo-planar imaging (SE-EPI) and turbo spin-echo (TSE). Here, we compare these two-dimensional (2D) imaging schemes to evaluate the optimal imaging scheme for pulsed ASL (PASL) assessment of human kidney cortex perfusion at 3 T. Ten healthy volunteers with normal renal function were scanned using each 2D multi-slice imaging scheme, in combination with a respiratory triggered flow-sensitive alternating inversion recovery (FAIR) ASL scheme on a 3 T Philips Achieva scanner. All volunteers returned for a second identical scan session within two weeks of the first scan session. Comparisons were made between the imaging schemes in terms of perfusion-weighted image (PWI) signal-to-noise ratio (SNR) and perfusion quantification, temporal SNR (tSNR), spatial coverage, and repeatability. For each imaging scheme, the renal cortex perfusion was calculated (bFFE: 276 ± 29 mL/100g/min, GE-EPI: 222 ± 18 mL/100g/min, SE-EPI: 201 ± 36 mL/100g/min, and TSE: 200 ± 20 mL/100g/min). Perfusion was found to be higher for GE-based readouts when compared with SE-based readouts, with significantly higher measured perfusion for the bFFE readout when compared with all other schemes (p < 0.05), attributed to the greater vascular signal present. Despite the PWI-SNR being significantly lower for SE-EPI when compared with all other schemes (p < 0.05), the SE-EPI readout gave the highest tSNR, and was found to be the most reproducible scheme for the assessment of kidney cortex, with a coefficient of variation (CoV) of 17.2%, whilst minimizing variability of the perfusion-weighted signal across slices for whole-kidney perfusion assessment. For the assessment of kidney cortex perfusion using 2D readout schemes, SE-EPI provides optimal tSNR, minimal variability across slices, and repeatable data acquired in a short scan time with low specific absorption rate.
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Li LP, Thacker J, Li W, Tan H, Wang C, Kohn O, Sprague S, Prasad P. Consistency of Multiple Renal Functional MRI Measurements Over 18 Months. J Magn Reson Imaging 2018. [PMID: 29517835 DOI: 10.1002/jmri.26001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Identification of patients with progressive chronic kidney disease (CKD) and those likely to respond to candidate therapeutics is urgently needed. Functional MRI measurements have shown promise. However, knowledge about the consistency of the measurements is essential to conduct longitudinal studies. PURPOSE/HYPOTHESIS To investigate the consistency of repeated functional MRI measurements in healthy subjects. STUDY TYPE Prospective, longitudinal study. SUBJECTS Seventeen healthy subjects were examined on two different occasions, 18 months apart. FIELD STRENGTH/SEQUENCE Multiple gradient-recalled-echo, 2D navigator-gated flow-sensitive alternating inversion recovery True-FISP and spin-echo planar diffusion-weighted sequences were used on a 3T scanner. Images were acquired on two different scanner configurations. ASSESSMENT Blood oxygenation level-dependent (BOLD) R2*, arterial spin labeling (ASL) perfusion-derived blood flow (BF) and apparent diffusion coefficient (ADC) maps were analyzed using a custom image processing toolbox. Regions of interest (ROIs) were placed on renal cortex, medulla, and whole kidney. Multiple researchers were involved in defining the ROIs. STATISTICAL TESTS Intra- and intersubject coefficients of variation (CV) and Bland-Altman plots were used to measure consistency and evaluate bias in the measurements. A nonparametric Wilcoxon test was used to compare differences between two timepoints. RESULTS The intrasubject CV for R2* and ADC were 6.8% and 5.3% with small (-3.8 and 5.3%) bias, respectively, comparing baseline and 18-month data. Intrasubject CV for renal cortex BF was higher (18.7%) compared to R2* and ADC, but comparable to prior literature values over shorter durations. It also exhibited a larger bias (-15.4%) between two timepoints and significantly lower values (P = 0.022) at 18-month data. DATA CONCLUSION All three MRI parameters over 18 months, even with a scanner upgrade and involving multiple observers, showed good consistency. These results are useful for the interpretation of longitudinal data and support the use of these methods to monitor progression in patients with CKD. LEVEL OF EVIDENCE 1 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2018;48:514-521.
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Affiliation(s)
- Lu-Ping Li
- Radiology, Northshore University HealthSystem, Evanston, Illinois, USA.,Pritzker School of Medicine, University of Chicago, Chicago, Illinois, USA
| | - Jon Thacker
- Biomedical Engineering, Northwestern University, Evanston, Illinois, USA
| | - Wei Li
- Radiology, Northshore University HealthSystem, Evanston, Illinois, USA.,Pritzker School of Medicine, University of Chicago, Chicago, Illinois, USA
| | - Huan Tan
- Radiology, Northshore University HealthSystem, Evanston, Illinois, USA
| | - Chi Wang
- Center for Biomedical Research & Informatics, Northshore University HealthSystem, Evanston, Illinois, USA
| | - Orly Kohn
- Medicine, University of Chicago, Chicago, Illinois, USA
| | - Stuart Sprague
- Pritzker School of Medicine, University of Chicago, Chicago, Illinois, USA.,Medicine, Northshore University HealthSystem, Evanston, Illinois, USA
| | - Pottumarthi Prasad
- Radiology, Northshore University HealthSystem, Evanston, Illinois, USA.,Pritzker School of Medicine, University of Chicago, Chicago, Illinois, USA
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32
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Non-Invasive Renal Perfusion Imaging Using Arterial Spin Labeling MRI: Challenges and Opportunities. Diagnostics (Basel) 2018; 8:diagnostics8010002. [PMID: 29303965 PMCID: PMC5871985 DOI: 10.3390/diagnostics8010002] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 12/25/2017] [Accepted: 01/02/2018] [Indexed: 12/28/2022] Open
Abstract
Tissue perfusion allows for delivery of oxygen and nutrients to tissues, and in the kidneys is also a key determinant of glomerular filtration. Quantification of regional renal perfusion provides a potential window into renal (patho) physiology. However, non-invasive, practical, and robust methods to measure renal perfusion remain elusive, particularly in the clinic. Arterial spin labeling (ASL), a magnetic resonance imaging (MRI) technique, is arguably the only available method with potential to meet all these needs. Recent developments suggest its viability for clinical application. This review addresses several of these developments and discusses remaining challenges with the emphasis on renal imaging in human subjects.
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33
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Qin L, Sun ZY, Cheng K, Liu SW, Pang JX, Xia LM, Chen WH, Cheng Z, Chen JX. Zwitterionic Manganese and Gadolinium Metal-Organic Frameworks as Efficient Contrast Agents for in Vivo Magnetic Resonance Imaging. ACS APPLIED MATERIALS & INTERFACES 2017; 9:41378-41386. [PMID: 29144731 DOI: 10.1021/acsami.7b09608] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Two water-stable three-dimensional Mn- and Gd-based metal-organic frameworks (MOFs), {[Mn2(Cmdcp)2(H2O)2]·H2O}n (1) and {[Gd(Cmdcp)(H2O)3](NO3)·3H2O}n (2, H3CmdcpBr = N-(4-carboxy benzyl)-(3,5-dicarboxyl)pyridinium bromide), have been prepared and analyzed. In vitro magnetic resonance imaging indicated that MOFs 1 and 2 possess relaxivity r1 values of 17.50 and 13.46 mM-1·S-1, respectively, which are superior to that of the control Gd-DTPA (r1 = 4.87 mM-1·S-1, DTPA = diethylene triamine pentaacetate). MOFs 1 and 2 also possessed good biocompatibility and low cytotoxicity against a model cell line. In vivo magnetic resonance images of treated Kunming mice indicated that kidneys showed remarkably positive signal enhancement after 15 min with intravenous administration of MOF 1 and the hyperintensity of both kidneys persisted for about 240 min with no obvious tissue damage. MOF 1 is therefore promising in vivo probes for imaging intravascular diseases and renal dysfunction.
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Affiliation(s)
- Liang Qin
- Guangdong Provincial Key Laboratory of New Drug Screening and Guangzhou Key Laboratory of Drug Research for Emerging Virus Prevention and Treatment, School of Pharmaceutical Sciences, Southern Medical University , Guangzhou 510515, China
- School of Chemistry and Chemical Engineering, Zhaoqing University , Zhaoqing 526061, China
| | - Zi-Yan Sun
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology , 1095 Jiefang Avenue, Wuhan 430030, China
- Department of Radiology, School of Medicine, Stanford University , 1201 Welch Road, Lucas Center, Stanford, California 94305-5484, United States
| | - Kai Cheng
- Department of Radiology, School of Medicine, Stanford University , 1201 Welch Road, Lucas Center, Stanford, California 94305-5484, United States
| | - Shu-Wen Liu
- Guangdong Provincial Key Laboratory of New Drug Screening and Guangzhou Key Laboratory of Drug Research for Emerging Virus Prevention and Treatment, School of Pharmaceutical Sciences, Southern Medical University , Guangzhou 510515, China
| | - Jian-Xin Pang
- Guangdong Provincial Key Laboratory of New Drug Screening and Guangzhou Key Laboratory of Drug Research for Emerging Virus Prevention and Treatment, School of Pharmaceutical Sciences, Southern Medical University , Guangzhou 510515, China
| | - Li-Ming Xia
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology , 1095 Jiefang Avenue, Wuhan 430030, China
| | - Wen-Hua Chen
- Guangdong Provincial Key Laboratory of New Drug Screening and Guangzhou Key Laboratory of Drug Research for Emerging Virus Prevention and Treatment, School of Pharmaceutical Sciences, Southern Medical University , Guangzhou 510515, China
| | - Zhen Cheng
- Department of Radiology, School of Medicine, Stanford University , 1201 Welch Road, Lucas Center, Stanford, California 94305-5484, United States
| | - Jin-Xiang Chen
- Guangdong Provincial Key Laboratory of New Drug Screening and Guangzhou Key Laboratory of Drug Research for Emerging Virus Prevention and Treatment, School of Pharmaceutical Sciences, Southern Medical University , Guangzhou 510515, China
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Cox EF, Buchanan CE, Bradley CR, Prestwich B, Mahmoud H, Taal M, Selby NM, Francis ST. Multiparametric Renal Magnetic Resonance Imaging: Validation, Interventions, and Alterations in Chronic Kidney Disease. Front Physiol 2017; 8:696. [PMID: 28959212 PMCID: PMC5603702 DOI: 10.3389/fphys.2017.00696] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 08/30/2017] [Indexed: 12/15/2022] Open
Abstract
Background: This paper outlines a multiparametric renal MRI acquisition and analysis protocol to allow non-invasive assessment of hemodynamics (renal artery blood flow and perfusion), oxygenation (BOLD T2*), and microstructure (diffusion, T1 mapping). Methods: We use our multiparametric renal MRI protocol to provide (1) a comprehensive set of MRI parameters [renal artery and vein blood flow, perfusion, T1, T2*, diffusion (ADC, D, D*, fp), and total kidney volume] in a large cohort of healthy participants (127 participants with mean age of 41 ± 19 years) and show the MR field strength (1.5 T vs. 3 T) dependence of T1 and T2* relaxation times; (2) the repeatability of multiparametric MRI measures in 11 healthy participants; (3) changes in MRI measures in response to hypercapnic and hyperoxic modulations in six healthy participants; and (4) pilot data showing the application of the multiparametric protocol in 11 patients with Chronic Kidney Disease (CKD). Results: Baseline measures were in-line with literature values, and as expected, T1-values were longer at 3 T compared with 1.5 T, with increased T1 corticomedullary differentiation at 3 T. Conversely, T2* was longer at 1.5 T. Inter-scan coefficients of variation (CoVs) of T1 mapping and ADC were very good at <2.9%. Intra class correlations (ICCs) were high for cortex perfusion (0.801), cortex and medulla T1 (0.848 and 0.997 using SE-EPI), and renal artery flow (0.844). In response to hypercapnia, a decrease in cortex T2* was observed, whilst no significant effect of hyperoxia on T2* was found. In CKD patients, renal artery and vein blood flow, and renal perfusion was lower than for healthy participants. Renal cortex and medulla T1 was significantly higher in CKD patients compared to healthy participants, with corticomedullary T1 differentiation reduced in CKD patients compared to healthy participants. No significant difference was found in renal T2*. Conclusions: Multiparametric MRI is a powerful technique for the assessment of changes in structure, hemodynamics, and oxygenation in a single scan session. This protocol provides the potential to assess the pathophysiological mechanisms in various etiologies of renal disease, and to assess the efficacy of drug treatments.
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Affiliation(s)
- Eleanor F Cox
- Sir Peter Mansfield Imaging Centre, University of NottinghamNottingham, United Kingdom
| | - Charlotte E Buchanan
- Sir Peter Mansfield Imaging Centre, University of NottinghamNottingham, United Kingdom
| | - Christopher R Bradley
- Sir Peter Mansfield Imaging Centre, University of NottinghamNottingham, United Kingdom
| | - Benjamin Prestwich
- Sir Peter Mansfield Imaging Centre, University of NottinghamNottingham, United Kingdom
| | - Huda Mahmoud
- Centre for Kidney Research and Innovation, Royal Derby Hospital, University of NottinghamDerby, United Kingdom
| | - Maarten Taal
- Centre for Kidney Research and Innovation, Royal Derby Hospital, University of NottinghamDerby, United Kingdom
| | - Nicholas M Selby
- Centre for Kidney Research and Innovation, Royal Derby Hospital, University of NottinghamDerby, United Kingdom
| | - Susan T Francis
- Sir Peter Mansfield Imaging Centre, University of NottinghamNottingham, United Kingdom
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Eikefjord E, Andersen E, Hodneland E, Hanson EA, Sourbron S, Svarstad E, Lundervold A, Rørvik JT. Dynamic contrast-enhanced MRI measurement of renal function in healthy participants. Acta Radiol 2017; 58:748-757. [PMID: 27694276 DOI: 10.1177/0284185116666417] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background High repeatability, accuracy, and precision for renal function measurements need to be achieved to establish renal dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) as a clinically useful diagnostic tool. Purpose To investigate the repeatability, accuracy, and precision of DCE-MRI measured renal perfusion and glomerular filtration rate (GFR) using iohexol-GFR as the reference method. Material and Methods Twenty healthy non-smoking volunteers underwent repeated DCE-MRI and an iohexol-GFR within a period of 10 days. Single-kidney (SK) MRI measurements of perfusion (blood flow, Fb) and filtration (GFR) were derived from parenchymal intensity time curves fitted to a two-compartment filtration model. The repeatability of the SK-MRI measurements was assessed using coefficient of variation (CV). Using iohexol-GFR as reference method, the accuracy of total MR-GFR was determined by mean difference (MD) and precision by limits of agreement (LoA). Results SK-Fb (MR1, 345 ± 84; MR2, 371 ± 103 mL/100 mL/min) and SK-GFR (MR1, 52 ± 14; MR2, 54 ± 10 mL/min/1.73 m2) measurements achieved a repeatability (CV) in the range of 15-22%. With reference to iohexol-GFR, MR-GFR was determined with a low mean difference but high LoA (MR1, MD 1.5 mL/min/1.73 m2, LoA [-42, 45]; MR2, MD 6.1 mL/min/1.73 m2, LoA [-26, 38]). Eighty percent and 90% of MR-GFR measurements were determined within ± 30% of the iohexol-GFR for MR1 and MR2, respectively. Conclusion Good repeatability of SK-MRI measurements and good agreement between MR-GFR and iohexol-GFR provide a high clinical potential of DCE-MRI for renal function assessment. A moderate precision in MR-derived estimates indicates that the method cannot yet be used in clinical routine.
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Affiliation(s)
- Eli Eikefjord
- Department of Radiology, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Erling Andersen
- Department of Radiology, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Engineering, Haukeland University Hospital, Bergen, Norway
| | - Erlend Hodneland
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
- Christian Michelsen Research (CMR) AS, Bergen, Norway
| | - Erik A Hanson
- Department of Mathematics, University of Bergen, Bergen, Norway
| | - Steven Sourbron
- Faculty of Medicine and Health, University of Leeds, Leeds, UK
| | - Einar Svarstad
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
- Department of Medicine, Haukeland University Hospital, Bergen, Norway
| | - Arvid Lundervold
- Department of Radiology, Haukeland University Hospital, Bergen, Norway
- Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Jarle T Rørvik
- Department of Radiology, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
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36
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van Eijs MJM, van Zuilen AD, de Boer A, Froeling M, Nguyen TQ, Joles JA, Leiner T, Verhaar MC. Innovative Perspective: Gadolinium-Free Magnetic Resonance Imaging in Long-Term Follow-Up after Kidney Transplantation. Front Physiol 2017; 8:296. [PMID: 28559850 PMCID: PMC5432553 DOI: 10.3389/fphys.2017.00296] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 04/24/2017] [Indexed: 12/23/2022] Open
Abstract
Since the mid-1980s magnetic resonance imaging (MRI) has been investigated as a non- or minimally invasive tool to probe kidney allograft function. Despite this long-standing interest, MRI still plays a subordinate role in daily practice of transplantation nephrology. With the introduction of new functional MRI techniques, administration of exogenous gadolinium-based contrast agents has often become unnecessary and true non-invasive assessment of allograft function has become possible. This raises the question why application of MRI in the follow-up of kidney transplantation remains restricted, despite promising results. Current literature on kidney allograft MRI is mainly focused on assessment of (sub) acute kidney injury after transplantation. The aim of this review is to survey whether MRI can provide valuable diagnostic information beyond 1 year after kidney transplantation from a mechanistic point of view. The driving force behind chronic allograft nephropathy is believed to be chronic hypoxia. Based on this, techniques that visualize kidney perfusion and oxygenation, scarring, and parenchymal inflammation deserve special interest. We propose that functional MRI mechanistically provides tools for diagnostic work-up in long-term follow-up of kidney allografts.
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Affiliation(s)
- Mick J M van Eijs
- Department of Nephrology and Hypertension, University Medical Center UtrechtUtrecht, Netherlands
| | - Arjan D van Zuilen
- Department of Nephrology and Hypertension, University Medical Center UtrechtUtrecht, Netherlands
| | - Anneloes de Boer
- Department of Radiology, University Medical Center UtrechtUtrecht, Netherlands
| | - Martijn Froeling
- Department of Radiology, University Medical Center UtrechtUtrecht, Netherlands
| | - Tri Q Nguyen
- Department of Pathology, University Medical Center UtrechtUtrecht, Netherlands
| | - Jaap A Joles
- Department of Nephrology and Hypertension, University Medical Center UtrechtUtrecht, Netherlands
| | - Tim Leiner
- Department of Radiology, University Medical Center UtrechtUtrecht, Netherlands
| | - Marianne C Verhaar
- Department of Nephrology and Hypertension, University Medical Center UtrechtUtrecht, Netherlands
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37
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Zhang JL. Functional Magnetic Resonance Imaging of the Kidneys-With and Without Gadolinium-Based Contrast. Adv Chronic Kidney Dis 2017; 24:162-168. [PMID: 28501079 DOI: 10.1053/j.ackd.2017.03.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Assessment of renal function with magnetic resonance imaging (MRI) has been actively explored in the past decade. In this review, we introduce the principle of MRI and review recent progress of MRI methods (contrast enhanced and noncontrast) in assessing renal function. Contrast-enhanced MRI using ultra-low dose of gadolinium-based agent has been validated for measuring single-kidney glomerular filtration rate and renal plasma flow accurately. For routine functional test, contrast-enhanced MRI may not replace the simple serum-creatinine method. However, for patients with renal diseases, it is often worthy to perform MRI to accurately monitor renal function, particularly for the diseased kidney. As contrast-enhanced MRI is already an established clinical tool for characterizing renal structural abnormalities, including renal mass and ureteral obstruction, it is possible to adapt the clinical MRI protocol to measure single-kidney glomerular filtration rate and renal plasma flow, as demonstrated by recent studies. What makes MRI unique is the promise of its noncontrast methods. These methods include arterial spin labeling for tissue perfusion, blood oxygen-level dependent for blood and tissue oxygenation, and diffusion-weighted imaging for water diffusion. For each method, we reviewed recent findings and summarized challenges.
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Mora-Gutiérrez JM, Garcia-Fernandez N, Slon Roblero MF, Páramo JA, Escalada FJ, Wang DJ, Benito A, Fernández-Seara MA. Arterial spin labeling MRI is able to detect early hemodynamic changes in diabetic nephropathy. J Magn Reson Imaging 2017; 46:1810-1817. [PMID: 28383796 DOI: 10.1002/jmri.25717] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Accepted: 03/15/2017] [Indexed: 11/06/2022] Open
Abstract
PURPOSE To investigate whether arterial spin labeling (ASL) MRI could detect renal hemodynamic impairment in diabetes mellitus (DM) along different stages of chronic kidney disease (CKD). MATERIALS AND METHODS Three Tesla (3T) ASL-MRI was performed to evaluate renal blood flow (RBF) in 91 subjects (46 healthy volunteers and 45 type 2 diabetic patients). Patients were classified according to their estimated glomerular filtration rate (eGFR) as group I (eGFR > 60 mL/min/1.73 m2 ), group II (60 ≥ eGFR>30 mL/min/1.73 m2 ), or group III (eGFR ≤ 30 mL/min/1.73 m2 ), to determine differences depending on renal function. Studies were performed at 3T using a 12-channel flexible body array combined with the spine array coil as receiver. RESULTS A 28% reduction in cortical RBF was seen in diabetics in comparison with healthy controls (185.79 [54.60] versus 258.83 [37.96] mL/min/100 g, P < 3 × 10-6 ). Differences were also seen between controls and diabetic patients despite normal eGFR and absence of overt albuminuria (RBF [mL/min/100 g]: controls=258.83 [37.96], group I=208.89 [58.83], P = 0.0018; eGFR [mL/min/1.73 m2 ]: controls = 95.50 [12.60], group I = 82.00 [20.76], P > 0.05; albumin-creatinine ratio [mg/g]: controls = 3.50 [4.45], group I = 17.50 [21.20], P > 0.05). A marked decrease in RBF was noted a long with progression of diabetic nephropathy (DN) through the five stages of CKD (χ2 = 43.58; P = 1.85 × 10-9 ). Strong correlation (r = 0.62; P = 4 × 10-10 ) was obtained between RBF and GFR estimated by cystatin C. CONCLUSION ASL-MRI is able to quantify early renal perfusion impairment in DM, as well as changes according to different CKD stages of DN. In addition, we demonstrated a correlation of RBF quantified by ASL and GFR estimated by cystatin C. LEVEL OF EVIDENCE 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1810-1817.
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Affiliation(s)
| | | | | | - Jose A Páramo
- Atherosclerosis Research Laboratory, CIMA, University of Navarra, Pamplona, Spain
| | | | - Danny Jj Wang
- Laboratory of Functional MRI Technology (LOFT) Stevens Neuroimaging and Informatics Institute University of Southern California, Los Angeles, California, USA
| | | | - María A Fernández-Seara
- Radiology, Clínica Universidad de Navarra, Spain.,Adjunct Associate Professor of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Kim DW, Shim WH, Yoon SK, Oh JY, Kim JK, Jung H, Matsuda T, Kim D. Measurement of arterial transit time and renal blood flow using pseudocontinuous ASL MRI with multiple post-labeling delays: Feasibility, reproducibility, and variation. J Magn Reson Imaging 2017; 46:813-819. [PMID: 28092411 DOI: 10.1002/jmri.25634] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 12/28/2016] [Indexed: 01/16/2023] Open
Abstract
PURPOSE To evaluate the feasibility, reproducibility, and variation of renal perfusion and arterial transit time (ATT) using pseudocontinuous arterial spin labeling magnetic resonance imaging (PCASL MRI) in healthy volunteers. MATERIALS AND METHODS PCASL MRI at 3T was performed in 25 healthy volunteers on two different occasions. The ATT and ATT-corrected renal blood flow (ATT-cRBF) were calculated at four different post-labeling delay points (0.5, 1.0, 1.5, and 2.0 s) and evaluated for each kidney and subject. The intraclass correlation (ICC) and Bland-Altman plot were used to assess the reproducibility of the PCASL MRI technique. The within-subject coefficient of variance was determined. RESULTS Results were obtained for 46 kidneys of 23 subjects with a mean age of 38.6 ± 9.8 years and estimated glomerular filtration rate (eGFR) of 89.1 ± 21.2 ml/min/1.73 m2 . Two subjects failed in the ASL MRI examination. The mean cortical and medullary ATT-cRBF for the subjects were 215 ± 65 and 81 ± 21 ml/min/100 g, respectively, and the mean cortical and medullary ATT were 1141 ± 262 and 1123 ± 245 msec, correspondingly. The ICC for the cortical ATT-cRBF was 0.927 and the within-subject coefficient of variance was 14.4%. The ICCs for the medullary ATT-cRBF and the cortical and medullary ATT were poor. The Bland-Altman plot for cortical RBF showed good agreement between the two measurements. CONCLUSION PCASL MRI is a feasible and reproducible method for measuring renal cortical perfusion. In contrast, ATT for the renal cortex and medulla has poor reproducibility and high variation. LEVEL OF EVIDENCE 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;46:813-819.
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Affiliation(s)
- Dong Won Kim
- Department of Radiology, Dong-A University College of Medicine, Busan, South Korea
| | - Woo Hyun Shim
- Department of Radiology, Research Institute of Radiology, Bioimaging Infrastructure, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.,Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
| | - Seong Kuk Yoon
- Department of Radiology, Dong-A University College of Medicine, Busan, South Korea
| | - Jong Yeong Oh
- Department of Radiology, Dong-A University College of Medicine, Busan, South Korea
| | - Jeong Kon Kim
- Department of Radiology, Research Institute of Radiology, Bioimaging Infrastructure, 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
| | - Hoesu Jung
- Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
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Zöllner FG, Gaa T, Zimmer F, Ong MM, Riffel P, Hausmann D, Schoenberg SO, Weis M. [Quantitative perfusion imaging in magnetic resonance imaging]. Radiologe 2016; 56:113-23. [PMID: 26796337 DOI: 10.1007/s00117-015-0068-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
CLINICAL/METHODICAL ISSUE Magnetic resonance imaging (MRI) is recognized for its superior tissue contrast while being non-invasive and free of ionizing radiation. Due to the development of new scanner hardware and fast imaging techniques during the last decades, access to tissue and organ functions became possible. One of these functional imaging techniques is perfusion imaging with which tissue perfusion and capillary permeability can be determined from dynamic imaging data. STANDARD RADIOLOGICAL METHODS Perfusion imaging by MRI can be performed by two approaches, arterial spin labeling (ASL) and dynamic contrast-enhanced (DCE) MRI. While the first method uses magnetically labelled water protons in arterial blood as an endogenous tracer, the latter involves the injection of a contrast agent, usually gadolinium (Gd), as a tracer for calculating hemodynamic parameters. PERFORMANCE Studies have demonstrated the potential of perfusion MRI for diagnostics and also for therapy monitoring. ACHIEVEMENTS The utilization and application of perfusion MRI are still restricted to specialized centers, such as university hospitals. A broad application of the technique has not yet been implemented. PRACTICAL RECOMMENDATIONS The MRI perfusion technique is a valuable tool that might come broadly available after implementation of standards on European and international levels. Such efforts are being promoted by the respective professional bodies.
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Affiliation(s)
- F G Zöllner
- Computerunterstützte Klinische Medizin, Medizinische Fakultät Mannheim, Universität Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Deutschland.
| | - T Gaa
- Computerunterstützte Klinische Medizin, Medizinische Fakultät Mannheim, Universität Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Deutschland
| | - F Zimmer
- Computerunterstützte Klinische Medizin, Medizinische Fakultät Mannheim, Universität Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Deutschland
| | - M M Ong
- Institut für Klinische Radiologie und Nuklearmedizin, Universitätsmedizin Mannheim, Medizinische Fakultät Mannheim, Universität Heidelberg, Mannheim, Deutschland
| | - P Riffel
- Institut für Klinische Radiologie und Nuklearmedizin, Universitätsmedizin Mannheim, Medizinische Fakultät Mannheim, Universität Heidelberg, Mannheim, Deutschland
| | - D Hausmann
- Institut für Klinische Radiologie und Nuklearmedizin, Universitätsmedizin Mannheim, Medizinische Fakultät Mannheim, Universität Heidelberg, Mannheim, Deutschland
| | - S O Schoenberg
- Institut für Klinische Radiologie und Nuklearmedizin, Universitätsmedizin Mannheim, Medizinische Fakultät Mannheim, Universität Heidelberg, Mannheim, Deutschland
| | - M Weis
- Institut für Klinische Radiologie und Nuklearmedizin, Universitätsmedizin Mannheim, Medizinische Fakultät Mannheim, Universität Heidelberg, Mannheim, Deutschland
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Becker AS, Rossi C. Renal Arterial Spin Labeling Magnetic Resonance Imaging. Nephron Clin Pract 2016; 135:1-5. [PMID: 27760424 DOI: 10.1159/000450797] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Accepted: 09/06/2016] [Indexed: 12/13/2022] Open
Abstract
Arterial spin labeling (ASL) MRI allows the quantification of tissue perfusion without administration of exogenous contrast agents. Patients with reduced renal function or other contraindications to Gadolinium-based contrast media may benefit from the non-invasive monitoring of tissue microcirculation. So far, only few studies have investigated the sensitivity, the specificity and the reliability of the ASL techniques for the assessment of renal perfusion. Moreover, only little is known about the interplay between ASL markers of perfusion and functional renal filtration parameters. In this editorial, we discuss the main technical issues related to the quantification of renal perfusion by ASL and, in particular, the latest results in patients with kidney disorders.
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Affiliation(s)
- Anton S Becker
- Department of Diagnostic and Interventional Radiology, University Hospital Zurich, Zurich, Switzerland
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Husain-Syed F, Slutsky AS, Ronco C. Lung–Kidney Cross-Talk in the Critically Ill Patient. Am J Respir Crit Care Med 2016; 194:402-14. [DOI: 10.1164/rccm.201602-0420cp] [Citation(s) in RCA: 131] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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Gillis KA, McComb C, Patel RK, Stevens KK, Schneider MP, Radjenovic A, Morris STW, Roditi GH, Delles C, Mark PB. Non-Contrast Renal Magnetic Resonance Imaging to Assess Perfusion and Corticomedullary Differentiation in Health and Chronic Kidney Disease. Nephron Clin Pract 2016; 133:183-92. [PMID: 27362585 DOI: 10.1159/000447601] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 06/10/2016] [Indexed: 11/19/2022] Open
Abstract
AIMS Arterial spin labelling (ASL) MRI measures perfusion without administration of contrast agent. While ASL has been validated in animals and healthy volunteers (HVs), application to chronic kidney disease (CKD) has been limited. We investigated the utility of ASL MRI in patients with CKD. METHODS We studied renal perfusion in 24 HVs and 17 patients with CKD (age 22-77 years, 40% male) using ASL MRI at 3.0T. Kidney function was determined using estimated glomerular filtration rate (eGFR). T1 relaxation time was measured using modified look-locker inversion and xFB02;ow-sensitive alternating inversion recovery true-fast imaging and steady precession was performed to measure cortical and whole kidney perfusion. RESULTS T1 was higher in CKD within cortex and whole kidney, and there was association between T1 time and eGFR. No association was seen between kidney size and volume and either T1, or ASL perfusion. Perfusion was lower in CKD in cortex (136 ± 37 vs. 279 ± 69 ml/min/100 g; p < 0.001) and whole kidney (146 ± 24 vs. 221 ± 38 ml/min/100 g; p < 0.001). There was significant, negative, association between T1 longitudinal relaxation time and ASL perfusion in both the cortex (r = -0.75, p < 0.001) and whole kidney (r = -0.50, p < 0.001). There was correlation between eGFR and both cortical (r = 0.73, p < 0.01) and whole kidney (r = 0.69, p < 0.01) perfusion. CONCLUSIONS Significant differences in renal structure and function were demonstrated using ASL MRI. T1 may be representative of structural changes associated with CKD; however, further investigation is required into the pathological correlates of reduced ASL perfusion and increased T1 time in CKD.
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Affiliation(s)
- Keith A Gillis
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
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Shimizu K, Kosaka N, Fujiwara Y, Matsuda T, Yamamoto T, Tsuchida T, Tsuchiyama K, Oyama N, Kimura H. Arterial Transit Time-corrected Renal Blood Flow Measurement with Pulsed Continuous Arterial Spin Labeling MR Imaging. Magn Reson Med Sci 2016; 16:38-44. [PMID: 27170422 PMCID: PMC5600042 DOI: 10.2463/mrms.mp.2015-0117] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Purpose: The importance of arterial transit time (ATT) correction for arterial spin labeling MRI has been well debated in neuroimaging, but it has not been well evaluated in renal imaging. The purpose of this study was to evaluate the feasibility of pulsed continuous arterial spin labeling (pcASL) MRI with multiple post-labeling delay (PLD) acquisition for measuring ATT-corrected renal blood flow (ATC-RBF). Materials and Methods: A total of 14 volunteers were categorized into younger (n = 8; mean age, 27.0 years) and older groups (n = 6; 64.8 years). Images of pcASL were obtained at three different PLDs (0.5, 1.0, and 1.5 s), and ATC-RBF and ATT were calculated using a single-compartment model. To validate ATC-RBF, a comparative study of effective renal plasma flow (ERPF) measured by 99mTc-MAG3 scintigraphy was performed. ATC-RBF was corrected by kidney volume (ATC-cRBF) for comparison with ERPF. Results: The younger group showed significantly higher ATC-RBF (157.68 ± 38.37 mL/min/100 g) and shorter ATT (961.33 ± 260.87 ms) than the older group (117.42 ± 24.03 mL/min/100 g and 1227.94 ± 226.51 ms, respectively; P < 0.05). A significant correlation was evident between ATC-cRBF and ERPF (P < 0.05, r = 0.47). With suboptimal single PLD (1.5 s) settings, there was no significant correlation between ERPF and kidney volume-corrected RBF calculated from single PLD data. Conclusion: Calculation of ATT and ATC-RBF by pcASL with multiple PLD was feasible in healthy volunteers, and differences in ATT and ATC-RBF were seen between the younger and older groups. Although ATT correction by multiple PLD acquisitions may not always be necessary for RBF quantification in the healthy subjects, the effect of ATT should be taken into account in renal ASL–MRI as debated in brain imaging.
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Affiliation(s)
- Kazuhiro Shimizu
- Department of Radiology, Faculty of Medical Sciences, University of Fukui
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Robson PM, Madhuranthakam AJ, Smith MP, Sun MRM, Dai W, Rofsky NM, Pedrosa I, Alsop DC. Volumetric Arterial Spin-labeled Perfusion Imaging of the Kidneys with a Three-dimensional Fast Spin Echo Acquisition. Acad Radiol 2016; 23:144-54. [PMID: 26521186 DOI: 10.1016/j.acra.2015.09.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 07/06/2015] [Accepted: 09/27/2015] [Indexed: 11/16/2022]
Abstract
RATIONALE AND OBJECTIVES Renal perfusion measurements using noninvasive arterial spin-labeled (ASL) magnetic resonance imaging techniques are gaining interest. Currently, focus has been on perfusion in the context of renal transplant. Our objectives were to explore the use of ASL in patients with renal cancer, and to evaluate three-dimensional (3D) fast spin echo (FSE) acquisition, a robust volumetric imaging method for abdominal applications. We evaluate 3D ASL perfusion magnetic resonance imaging in the kidneys compared to two-dimensional (2D) ASL in patients and healthy subjects. MATERIALS AND METHODS Isotropic resolution (2.6 × 2.6 × 2.8 mm(3)) 3D ASL using segmented FSE was compared to 2D single-shot FSE. ASL used pseudo-continuous labeling, suppression of background signal, and synchronized breathing. Quantitative perfusion values and signal-to-noise ratio (SNR) were compared between 3D and 2D ASL in four healthy volunteers and semiquantitative assessments were made by four radiologists in four patients with known renal masses (primary renal cell carcinoma). RESULTS Renal cortex perfusion in healthy subjects was 284 ± 21 mL/100 g/min, with test-retest repeatability of 8.8%. No significant differences were found between the quantitative perfusion value and SNR in volunteers between 3D ASL and 2D ASL, or in 3D ASL with synchronized or free breathing. In patients, semiquantitative assessment by radiologists showed no significant difference in image quality between 2D ASL and 3D ASL. In one case, 2D ASL missed a high perfusion focus in a mass that was seen by 3D ASL. CONCLUSIONS 3D ASL renal perfusion imaging provides isotropic-resolution images, with comparable quantitative perfusion values and image SNR in similar imaging time to single-slice 2D ASL.
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Affiliation(s)
- Philip M Robson
- Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, AN-226, Boston, MA 02215.
| | | | - Martin P Smith
- Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, AN-226, Boston, MA 02215
| | - Maryellen R M Sun
- Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, AN-226, Boston, MA 02215
| | - Weiying Dai
- Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, AN-226, Boston, MA 02215
| | - Neil M Rofsky
- University of Texas Southwestern Medical Center, Dallas, Texas
| | - Ivan Pedrosa
- University of Texas Southwestern Medical Center, Dallas, Texas
| | - David C Alsop
- Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, AN-226, Boston, MA 02215
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Feasibility of measuring renal blood flow by phase-contrast magnetic resonance imaging in patients with autosomal dominant polycystic kidney disease. Eur Radiol 2015; 26:683-92. [PMID: 26162576 PMCID: PMC4748006 DOI: 10.1007/s00330-015-3877-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Revised: 06/02/2015] [Accepted: 06/03/2015] [Indexed: 10/25/2022]
Abstract
OBJECTIVES Renal blood flow (RBF) has been shown to predict disease progression in autosomal dominant polycystic kidney disease (ADPKD). We investigated the feasibility and accuracy of phase-contrast RBF by MRI (RBFMRI) in ADPKD patients with a wide range of estimated glomerular filtration rate (eGFR) values. METHODS First, we validated RBFMRI measurement using phantoms simulating renal artery hemodynamics. Thereafter, we investigated in a test-set of 21 patients intra- and inter-observer coefficient of variation of RBFMRI. After validation, we measured RBFMRI in a cohort of 91 patients and compared the variability explained by characteristics indicative for disease severity for RBFMRI and RBF measured by continuous hippuran infusion. RESULTS The correlation in flow measurement using phantoms by phase-contrast MRI was high and fluid collection was high (CCC=0.969). Technical problems that precluded RBFMRI measurement occurred predominantly in patients with a lower eGFR (34% vs. 16%). In subjects with higher eGFRs, variability in RBF explained by disease characteristics was similar for RBFMRI compared to RBFHip, whereas in subjects with lower eGFRs, this was significantly less for RBFMRI. CONCLUSIONS Our study shows that RBF can be measured accurately in ADPKD patients by phase-contrast, but this technique may be less feasible in subjects with a lower eGFR. KEY POINTS Renal blood flow (RBF) can be accurately measured by phase-contrast MRI in ADPKD patients. RBF measured by phase-contrast is associated with ADPKD disease severity. RBF measurement by phase-contrast MRI may be less feasible in patients with an impaired eGFR.
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Cutajar M, Hilton R, Olsburgh J, Marks SD, Thomas DL, Banks T, Clark CA, Gordon I. Renal blood flow using arterial spin labelling MRI and calculated filtration fraction in healthy adult kidney donors Pre-nephrectomy and post-nephrectomy. Eur Radiol 2015; 25:2390-6. [PMID: 25666379 DOI: 10.1007/s00330-015-3594-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 12/21/2014] [Accepted: 01/12/2015] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Renal plasma flow (RPF) (derived from renal blood flow, RBF) and glomerular filtration rate (GFR) allow the determination of the filtration fraction (FF), which may have a role as a non-invasive renal biomarker. This is a hypothesis-generating pilot study assessing the effect of nephrectomy on renal function in healthy kidney donors. METHODS Eight living kidney donors underwent arterial spin labelling (ASL) magnetic resonance imaging (MRI) and GFR measurement prior to and 1 year after nephrectomy. Chromium-51 labelled ethylenediamine tetraacetic acid ((51)Cr-EDTA) with multi-blood sampling was undertaken and GFR calculated. The RBF and GFR obtained were used to calculate FF. RESULTS All donors showed an increase in single kidney GFR of 24 - 75 %, and all but two showed an increase in FF (-7 to +52 %) after nephrectomy. The increase in RBF, and hence RPF, post-nephrectomy was not as great as the increase in GFR in seven out of eight donors. As with any pilot study, the small number of donors and their relatively narrow age range are potential limiting factors. CONCLUSIONS The ability to measure RBF, and hence RPF, non-invasively, coupled with GFR measurement, allows calculation of FF, a biomarker that might provide a sensitive indicator of loss of renal reserve in potential donors. KEY POINTS • Non-invasive MRI measured renal blood flow and calculated renal plasma flow. • Effect of nephrectomy on blood flow and filtration in donors is presented. • Calculated filtration fraction may be a useful new kidney biomarker.
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Affiliation(s)
- Marica Cutajar
- Imaging and Biophysics Unit, Institute of Child Health, University College London, 30 Guilford Street, London, WC1N1EH, UK
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