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Ku MC, Fernández-Seara MA, Kober F, Niendorf T. Noninvasive Renal Perfusion Measurement Using Arterial Spin Labeling (ASL) MRI: Basic Concept. Methods Mol Biol 2021; 2216:229-239. [PMID: 33476003 PMCID: PMC9703206 DOI: 10.1007/978-1-0716-0978-1_13] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The kidney is a complex organ involved in the excretion of metabolic products as well as the regulation of body fluids, osmolarity, and homeostatic status. These functions are influenced in large part by alterations in the regional distribution of blood flow between the renal cortex and medulla. Renal perfusion is therefore a key determinant of glomerular filtration. Therefore the quantification of regional renal perfusion could provide important insights into renal function and renal (patho)physiology. Arterial spin labeling (ASL) based perfusion MRI techniques, can offer a noninvasive and reproducible way of measuring renal perfusion in animal models. This chapter addresses the basic concept of ASL-MRI.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This introduction chapter is complemented by two separate chapters describing the experimental procedure and data analysis.
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Affiliation(s)
- Min-Chi Ku
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | | | - Frank Kober
- Aix-Marseille Université, CNRS, Centre de Résonance Magnétique Biologique et Médicale (CRMBM), Marseille, France
| | - Thoralf Niendorf
- Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine (MDC) in the Helmholtz Association, Berlin, Germany
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Lee SK, Jang Y, Jung JW, Je H, Choi J. Comparison of Renal Blood Flow Using Maximum Slope-Based Computed Tomography Perfusion and Ultrasound Flow Probe in Healthy Dogs. Front Vet Sci 2020; 7:541747. [PMID: 33195514 PMCID: PMC7581705 DOI: 10.3389/fvets.2020.541747] [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: 03/10/2020] [Accepted: 09/04/2020] [Indexed: 11/15/2022] Open
Abstract
Computed tomography (CT) perfusion can analyze tissue perfusion and quantitative parameters, including blood flow, blood volume, and transit time. CT perfusion has been used for evaluating split renal function. However, its applicability in veterinary medicine was not validated. This study aimed to evaluate the correlation of renal blood flow (RBF) derived by maximum slope-based CT perfusion and an ultrasonic flow probe and assess the effect of the presence of a pre-existing contrast medium on CT perfusion in the kidneys. In five healthy purpose-bred beagles, CT perfusion was performed at the level of the left renal hila after injection of 1 mg/kg iohexol, during measuring RBF with an ultrasonic flow probe placed on the left renal artery. After post-contrast CT scan with injection of 2 mg/kg iohexol, CT perfusion scan was repeated with the same protocol used in the first perfusion study. The CT perfusion derived RBF was analyzed based on the maximum slope and was compared with the true RBF obtained using an ultrasonic flow probe. Results indicated that CT perfusion derived RBF was significantly correlated with true RBF, although CT perfusion derived RBF did not match the absolute value of the true RBF. It was correlated with the true RBF, even in the presence of a pre-existing contrast medium in the kidney. CT perfusion can estimate the change in individual renal perfusion non-invasively, and this method can be used supplementary to the conventional CT protocol in clinic.
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Affiliation(s)
- Sang-Kwon Lee
- Veterinary Medical Imaging, College of Veterinary Medicine and BK21 Plus Project Team, Chonnam National University, Gwangju, South Korea
| | - Youjung Jang
- Veterinary Medical Imaging, College of Veterinary Medicine and BK21 Plus Project Team, Chonnam National University, Gwangju, South Korea
| | - Jin-Woo Jung
- Veterinary Medical Imaging, College of Veterinary Medicine and BK21 Plus Project Team, Chonnam National University, Gwangju, South Korea
| | - Hyejin Je
- Veterinary Medical Imaging, College of Veterinary Medicine and BK21 Plus Project Team, Chonnam National University, Gwangju, South Korea
| | - Jihye Choi
- Veterinary Medical Imaging, College of Veterinary Medicine and BK21 Plus Project Team, Chonnam National University, Gwangju, South Korea
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Welsh AW, Fowlkes JB, Pinter SZ, Ives KA, Owens GE, Rubin JM, Kripfgans OD, Looney P, Collins SL, Stevenson GN. Three-dimensional US Fractional Moving Blood Volume: Validation of Renal Perfusion Quantification. Radiology 2019; 293:460-468. [PMID: 31573404 PMCID: PMC6800606 DOI: 10.1148/radiol.2019190248] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Background Three-dimensional (3D) fractional moving blood volume (FMBV) derived from 3D power Doppler US has been proposed for noninvasive approximation of perfusion. However, 3D FMBV has never been applied in animals against a ground truth. Purpose To determine the correlation between 3D FMBV and the reference standard of fluorescent microspheres (FMS) for measurement of renal perfusion in a porcine model. Materials and Methods From February 2017 to September 2017, adult pigs were administered FMS before and after measurement of renal 3D FMBV at baseline (100%) and approximately 75%, 50%, and 25% flow levels by using US machines from two different vendors. The 3D power Doppler US volumes were converted and segmented, and correlations between FMS and 3D FMBV were made with simple linear regression (r2). Similarity and reproducibility of manual segmentation were determined with the Dice similarity coefficient and 3D FMBV reproducibility (intraclass correlation coefficient [ICC]). Results Thirteen pigs were studied with 33 flow measurements. Kidney volume (mean Dice similarity coefficient ± standard deviation, 0.89 ± 0.01) and renal segmentation (coefficient of variation = 12.6%; ICC = 0.86) were consistent. The 3D FMBV calculations had high reproducibility (ICC = 0.97; 95% confidence interval: 0.96, 0.98). The 3D FMBV per-pig correlation showed excellent correlation for US machines from both vendors (mean r2 = 0.96 [range, 0.92-1.0] and 0.93 [range, 0.78-1.0], respectively). The correlation between 3D FMBV and perfusion measured with microspheres was high for both US machines (r2 = 0.80 [P < .001] and 0.70 [P < .001], respectively). Conclusion The strong correlation between three-dimensional (3D) fractional moving blood volume (FMBV) and fluorescent microspheres indicates that 3D FMBV shows excellent correlation to perfusion and good reproducibility. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Morrell et al in this issue.
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Affiliation(s)
- Alec W. Welsh
- School of Women’s and Children’s Health, Faculty of Medicine, University of New South Wales, Randwick, New South Wales, Australia
- Department of Maternal-Fetal Medicine, Royal Hospital for Women, Randwick, NSW, Australia
| | - J. Brian Fowlkes
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Stephen Z. Pinter
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Kimberly A Ives
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Gabe E Owens
- Department of Pediatrics, University of Michigan Health System, Ann Arbor, MI, USA
| | - Jonathan M. Rubin
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Oliver D Kripfgans
- Department of Radiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Pádraig Looney
- Nuffield Department of Women’s and Reproductive Health, University of Oxford, Oxford, United Kingdom
| | - Sally L. Collins
- Nuffield Department of Women’s and Reproductive Health, University of Oxford, Oxford, United Kingdom
- Fetal Medicine Unit, Women’s Centre, John Radcliffe Hospital, Oxford, United Kingdom
| | - Gordon N. Stevenson
- School of Women’s and Children’s Health, Faculty of Medicine, University of New South Wales, Randwick, New South Wales, Australia
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Morrell GR. Toward Rapid Noninvasive Measurement of Kidney Perfusion. Radiology 2019; 293:469-470. [PMID: 31577176 DOI: 10.1148/radiol.2019192035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Glen R Morrell
- From the Department of Radiology and Imaging Sciences, University of Utah, 30 North, 1900 East #1A071, Salt Lake City, UT 84132
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Jiang K, Ferguson CM, Abumoawad A, Saad A, Textor SC, Lerman LO. A modified two-compartment model for measurement of renal function using dynamic contrast-enhanced computed tomography. PLoS One 2019; 14:e0219605. [PMID: 31291361 PMCID: PMC6619810 DOI: 10.1371/journal.pone.0219605] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 06/27/2019] [Indexed: 12/14/2022] Open
Abstract
Objectives To validate and adapt a modified two-compartment model, originally developed for magnetic resonance imaging, for measuring human single-kidney glomerular filtration rate (GFR) and perfusion using dynamic contrast-enhanced computed tomography (DCE-CT). Methods This prospective study was approved by the institutional review board, and written informed consent was obtained from all patients. Thirty-eight patients with essential hypertension (EH, n = 13) or atherosclerotic renal artery stenosis (ARAS, n = 25) underwent renal DCE-CT for GFR and perfusion measurement using a modified two-compartment model. Iothalamate clearance was used to measure reference total GFR, which was apportioned into single-kidney GFR by renal blood flow. Renal perfusion was also calculated using a conventional deconvolution algorithm. Validation of GFR and perfusion and inter-observer reproducibility, were conducted by using the Pearson correlation and Bland-Altman analysis. Results Both the two-compartment model and iothalamate clearance detected in ARAS patients lower GFR in the stenotic compared to the contralateral and EH kidneys. GFRs measured by DCE-CT and iothalamate clearance showed a close match (r = 0.94, P<0.001, and mean difference 2.5±12.2mL/min). Inter-observer bias and variation in model-derived GFR (r = 0.97, P<0.001; mean difference, 0.3±7.7mL/min) were minimal. Renal perfusion by deconvolution agreed well with that by the compartment model when the blood transit delay from abdominal aorta to kidney was negligible. Conclusion The proposed two-compartment model faithfully depicts contrast dynamics using DCE-CT and may provide a reliable tool for measuring human single-kidney GFR and perfusion.
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Affiliation(s)
- Kai Jiang
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Christopher M. Ferguson
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Abdelrhman Abumoawad
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Ahmed Saad
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Stephen C. Textor
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Lilach O. Lerman
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail:
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Improved Peritoneal Cavity and Abdominal Organ Imaging Using a Biphasic Contrast Agent Protocol and Spectral Photon Counting Computed Tomography K-Edge Imaging. Invest Radiol 2019; 53:629-639. [PMID: 29794948 PMCID: PMC6291259 DOI: 10.1097/rli.0000000000000483] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVES To validate in vitro the capability of a high-spatial-resolution prototype spectral photon-counting computed tomography (SPCCT) scanner to differentiate between 2 contrast agents and to assess in vivo the image quality and the feasibility to image the peritoneal cavity in rats using the 2 contrast agents simultaneously within the vascular and peritoneal compartments. MATERIALS AND METHODS The authors performed SPCCT imaging (100 mAs, 120 kVp) with energy bin thresholds set to 30, 51, 64, 72, and 85 keV in vitro on a custom-made polyoxymethylene cylindrical phantom consisting of tubes with dilutions of both contrast agents and in vivo on 2 groups of adult rats using 2 injection protocols. Approval from the institutional animal ethics committee was obtained. One group received macrocylic gadolinium chelate intraperitoneal (IP) and iodine intravenous (IV) injections (protocol A, n = 3), whereas the second group received iodine IP and gadolinium IV (protocol B, n = 3). Helical scans were performed 35 minutes after IP injection and 20 seconds after IV injection. The SPCCT and contrast material images, that is, iodine and gadolinium maps, were reconstructed with a field of view of 160 mm, an isotropic voxel size of 250 μm, and a matrix size of 640 × 640 pixels using a soft reconstruction kernel. The SPCCT images were reconstructed with 2 different spatial resolutions to compare the image quality (sharpness, diagnostic quality, and organ visualization) of SPCCT (250 μm) with single-energy computed tomography (CT) (600 μm). Two radiologists evaluated the peritoneal opacification index in 13 regions (score = 0-3 per region) on each type of image. Concentrations of contrast agents were measured in the organs of interest. RESULTS In vitro, the concentration measurements correlated well with the expected concentrations. The linear regressions both had R values of 0.99, slopes of 0.84 and 0.87, and offsets at -0.52 and -0.38 mg/mL for iodine and gadolinium, respectively. In vivo, the SPCCT images were of better diagnostic quality, with increased sharpness compared with the CT-like images (P < 0.0001). Intraperitoneal diffusion was excellent, with similar peritoneal opacification index on SPCCT images and overlay of contrast material maps (P = 1) without a significant difference between protocol A (37.0 ± 1.7) and protocol B (35.3 ± 1.5) (P = 0.34). Only the contrast material maps demonstrated clear visual separation of the contrast agents, allowing specific quantification of the physiological enhancement in the liver, spleen, and kidney and the urinary clearance in the renal pelvis and bladder. Renal excretion of the contrast agents injected IP was observed and was consistent with blood diffusion. CONCLUSIONS Spectral photon-counting CT can be used to perform a complete peritoneal dual-contrast protocol, enabling a good assessment of the peritoneal cavity and abdominal organs in rats.
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Outcomes and Predictors of Endovascular Treatment for Type B Aortic Dissection Complicated by Unilateral Renal Ischemia. J Vasc Interv Radiol 2019; 30:973-978. [PMID: 30982637 DOI: 10.1016/j.jvir.2018.12.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 12/15/2018] [Accepted: 12/19/2018] [Indexed: 11/20/2022] Open
Abstract
PURPOSE This study investigated the outcomes of endovascular treatment for type B aortic dissection (TBAD) complicated by unilateral renal ischemia and determined the associated predictors. MATERIALS AND METHODS From January 2010 to December 2016, 44 patients (mean : 54 years of age) with TBAD complicated by a clearly involved unilateral renal artery and a decreased mean density of the unilateral renal parenchyma were enrolled. The volumes and mean densities of each kidney were generated with postprocessing software based on computed tomography angiography. The degree of renal malperfusion (RMD) was defined as the bilateral density difference-to-the mean density ratio of the healthy kidney. The primary outcomes were renal atrophy and renal dysfunction; the secondary outcomes were aorta-related complications. RESULTS The median follow-up time was 51 months (range: 12-102 months). During follow-up, unilateral renal atrophy and renal dysfunction were observed in 12 patients (27.3%) and 7 patients (15.9%), respectively. RMD showed a moderate predictive value for renal atrophy, with an area under the characteristic curve (AUC) of 0.78. The optimal cutoff value was 27% for RMD in terms of predicting renal atrophy (sensitivity: 91.7%; specificity: 56.2%). Moreover, aorta-related adverse events occurred in 14 patients (31.8%). Preoperative abnormal creatinine level was an independent risk factor for aorta-related complications (odds ratio [OR]: 17.5; P = 0.022) and renal dysfunction (OR: 14.2; P = 0.02). CONCLUSIONS Preoperative serum creatinine was an effective index used to predict renal and aortic outcomes in this patient cohort. Active imaging follow-up and aggressive endovascular intervention are suggested in patients with RMD >27%.
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Zhang YD, Xue CQ, Wu CJ, Tao J, Zhou WL, Shi HB. Feasibility of triphasic CT with a modified two-point Patlak plot to determine spit kidney glomerular filtration rate in clinical practice. Abdom Radiol (NY) 2017; 42:226-235. [PMID: 27503300 DOI: 10.1007/s00261-016-0858-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
PURPOSE To investigate whether triphasic CT with a simplified Patlak plot can be used in clinical practice for the estimate of split kidney glomerular filtration rate (SKGFR). MATERIALS AND METHODS The animal experiment included 15 rabbits that underwent 40 dynamic contrast-enhanced CT scans of the kidneys with 1.5 s time interval. Patlak-derived SKGFR was obtained using standard forty-point, two-point (unenhanced phase, arterial phase t α, and portovenous phase t β), and a modified two-point (MTP) (unenhanced, t α, t β, and a virtual t τ [t τ = (t α + t β)/2]) image data, respectively. The MTP-Patlak plot approach was then validated in 13 patients who underwent a triphasic renal contrast-enhanced CT examination. SKGFR measured by 99mTc-DTPA clearance was as a standard reference. RESULTS MTP-Patlak significantly reduced input function errors than two-point Patlak (21.1 ± 16.2 % vs 30.8 ± 15.2 %, p < 0.01) and showed good concordance with standard Patlak for measurement of SKGFR in animal experiment (1.20 ± 0.38 mL/g/min vs 1.51 ± 0.43 mL/g/min; linear correlation coefficient r = 0.87, p < 0.001). Human study showed that mean SKGFR was 45.7 mL/min (range, 26.5-86.2 mL/min) obtained from 99mTc-DTPA, and 38.2 mL/min (range, 18.6-79.3 mL/min) obtained from triphasic CT using MTP-Patlak plot. Linear correlation between the two methods was r = 0.75 (p < 0.01). The mean difference between SKGFRs as determined with the two methods was 7.4 ± 9.0 mL/min. CONCLUSION The MTP-Patlak approach, featured with simplicity, is feasible in a clinically indicated CT examination for the evaluation of split renal function.
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Affiliation(s)
- Yu-Dong Zhang
- Department of Radiology, The First Affiliated Hospital with Nanjing Medical University, 300, Guangzhou Road, Nanjing, 210009, Jiangsu Province, China.
| | - Chen-Qi Xue
- Department of Nuclear Medicine, The First Affiliated Hospital with Nanjing Medical University, Nanjing, 210009, China
| | - Chen-Jiang Wu
- Department of Radiology, The First Affiliated Hospital with Nanjing Medical University, 300, Guangzhou Road, Nanjing, 210009, Jiangsu Province, China
| | - Jun Tao
- Department of Urology, The First Affiliated Hospital with Nanjing Medical University, Nanjing, 210009, China
| | - Wan-Li Zhou
- Department of Urology, The First Affiliated Hospital with Nanjing Medical University, Nanjing, 210009, China
| | - Hai-Bin Shi
- Department of Radiology, The First Affiliated Hospital with Nanjing Medical University, 300, Guangzhou Road, Nanjing, 210009, Jiangsu Province, China
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El-Diasty MT, Gaballa G, Gad HM, Borg MA, Abou-Elghar ME, Sheir KZ, El-Diasty TA. Evaluation of CT perfusion parameters for assessment of split renal function in healthy donors. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2016. [DOI: 10.1016/j.ejrnm.2016.07.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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Grenier N, Merville P, Combe C. Radiologic imaging of the renal parenchyma structure and function. Nat Rev Nephrol 2016; 12:348-59. [DOI: 10.1038/nrneph.2016.44] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Yuan X, Zhang J, Quan C, Tian Y, Li H, Ao G. A Simplified Whole-Organ CT Perfusion Technique with Biphasic Acquisition: Preliminary Investigation of Accuracy and Protocol Feasibility in Kidneys. Radiology 2016; 279:254-61. [DOI: 10.1148/radiol.2015142757] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Cai XR, Zhou QC, Yu J, Feng YZ, Xian ZH, Yang WC, Mo XK. Assessment of renal function in patients with unilateral ureteral obstruction using whole-organ perfusion imaging with 320-detector row computed tomography. PLoS One 2015; 10:e0122454. [PMID: 25874690 PMCID: PMC4398441 DOI: 10.1371/journal.pone.0122454] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 02/11/2015] [Indexed: 12/02/2022] Open
Abstract
Background Obstructed nephropathy is a common complication of several disease processes. Accurate evaluation of the functional status of the obstructed kidney is important to achieve a good outcome. The purpose of this study was to investigate renal cortical and medullary perfusion changes associated with unilateral ureteral obstruction (UUO) using whole-organ perfusion imaging with 320-detector row computed tomography (CT). Methodology/Principle Findings Sixty-four patients with UUO underwent whole-organ CT perfusion imaging. Patients were divided into 3 groups, mild, moderate, and severe, based on hydronephrosis severity. Twenty sex- and age-matched patients without renal disease, who referred to abdominal CT, were chosen as control subjects. Mean cortical and medullary perfusion parameters of obstructed and contralateral kidneys were compared, and mean perfusion ratios between obstructed and contralateral kidneys were calculated and compared. Mean cortical or medullary blood flow (BF) and blood volume (BV) of the obstructed kidneys in the moderate UUO and BF, BV, and clearance (CL) in the severe UUO were significantly lower than those of the contralateral kidneys (p < 0.05). The mean cortical or medullary BF of the obstructed kidney in the moderate UUO, and BF, BV, and CL in the severe UUO were significantly lower than those of the kidneys in control subjects (p < 0.05). Mean cortical or medullary BF of the non-obstructed kidneys in the severe UUO were statistically greater than that of normal kidneys in control subjects (p < 0.05). An inverse correlation was observed between cortical and medullary perfusion ratios and grades of hydronephosis (p < 0.01). Conclusions/Significance Perfusion measurements of the whole kidney can be obtained with 320-detector row CT, and estimated perfusion ratios have potential for quantitatively evaluating UUO renal injury grades.
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Affiliation(s)
- Xiang-Ran Cai
- Medical Imaging Center, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong, P.R.China
- * E-mail:
| | - Qing-Chun Zhou
- Department of Urology, Nanhua Affiliated Hospital, Nanhua University, Hengyang, Hunan, P.R.China
| | - Juan Yu
- Department of Radiology, Shenzhen Second People’s Hospital, Shenzhen, Guangdong, P.R.China
| | - You-Zhen Feng
- Medical Imaging Center, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong, P.R.China
| | - Zhao-Hui Xian
- Medical Imaging Center, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong, P.R.China
| | - Wen-Cai Yang
- Medical Imaging Center, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong, P.R.China
| | - Xu-Kai Mo
- Medical Imaging Center, First Affiliated Hospital, Jinan University, Guangzhou, Guangdong, P.R.China
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Kwon SH, Saad A, Herrmann SM, Textor SC, Lerman LO. Determination of Single-Kidney Glomerular Filtration Rate in Human Subjects by Using CT. Radiology 2015; 276:490-8. [PMID: 25848903 DOI: 10.1148/radiol.2015141892] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
PURPOSE To test the hypothesis that computed tomography (CT)-derived measurements of single-kidney glomerular filtration rate (GFR) obtained in human subjects with 64-section CT agree with those obtained with iothalamate clearance, a rigorous reference standard. MATERIALS AND METHODS The institutional review board approved this HIPAA-compliant study, and written informed consent was obtained. Ninety-six patients (age range, 51-73 years; 46 men, 50 women) with essential (n = 56) or renovascular (n = 40) hypertension were prospectively studied in controlled conditions (involving sodium intake and renin-angiotensin blockade). Single-kidney perfusion, volume, and GFR were measured by using multidetector CT time-attenuation curves and were compared with GFR measured by using iothalamate clearance, as assigned to the right and left kidney according to relative volumes. The reproducibility of CT GFR over a 3-month period (n = 21) was assessed in patients with renal artery stenosis who were undergoing stable medical treatment. Statistical analysis included the t test, Wilcoxon signed rank test, linear regression, and Bland-Altman analysis. RESULTS CT GFR values were similar to those of iothalamate clearance (mean ± standard deviation, 38.2 mL/min ± 18 vs 41.6 mL/min ± 17; P = .062). Stenotic kidney CT GFR in patients with renal artery stenosis was lower than contralateral kidney GFR or essential hypertension single-kidney GFR (mean, 23.1 mL/min ± 13 vs 36.9 mL/min ± 17 [P = .0008] and 45.2 mL/min ± 16 [P = .019], respectively), as was iothalamate clearance (mean, 26.9 mL/min ± 14 vs 38.5 mL/min ± 15 [P = .0004] and 49.0 mL/min ± 14 [P = .001], respectively). CT GFR correlated well with iothalamate GFR (linear regression, CT GFR = 0.88*iothalamate GFR, r(2) = 0.89, P < .0001), and Bland-Altman analysis was used to confirm the agreement. CT GFR was also moderately reproducible in medically treated patients with renal artery stenosis (concordance coefficient correlation, 0.835) but was unaffected by revascularization (mean, 25.3 mL/min ± 15.2 vs 30.3 mL/min ± 18.5; P = .097). CONCLUSION CT assessments of single-kidney GFR are reproducible and agree well with a reference standard. CT can be useful to obtain minimally invasive estimates of bilateral single-kidney function in human subjects.
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Affiliation(s)
- Soon Hyo Kwon
- From the Division of Nephrology and Hypertension, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (S.H.K., A.S., S.M.H., S.C.T., L.O.L.) and Division of Nephrology, Soonchunhyang University Hospital, Seoul, South Korea (S.H.K.)
| | - Ahmed Saad
- From the Division of Nephrology and Hypertension, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (S.H.K., A.S., S.M.H., S.C.T., L.O.L.) and Division of Nephrology, Soonchunhyang University Hospital, Seoul, South Korea (S.H.K.)
| | - Sandra M Herrmann
- From the Division of Nephrology and Hypertension, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (S.H.K., A.S., S.M.H., S.C.T., L.O.L.) and Division of Nephrology, Soonchunhyang University Hospital, Seoul, South Korea (S.H.K.)
| | - Stephen C Textor
- From the Division of Nephrology and Hypertension, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (S.H.K., A.S., S.M.H., S.C.T., L.O.L.) and Division of Nephrology, Soonchunhyang University Hospital, Seoul, South Korea (S.H.K.)
| | - Lilach O Lerman
- From the Division of Nephrology and Hypertension, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (S.H.K., A.S., S.M.H., S.C.T., L.O.L.) and Division of Nephrology, Soonchunhyang University Hospital, Seoul, South Korea (S.H.K.)
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Contrast-enhanced ultrasound identifies reduced overall and regional renal perfusion during global hypoxia in piglets. Invest Radiol 2015; 49:540-6. [PMID: 24637585 DOI: 10.1097/rli.0000000000000053] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE It is well known from both clinical experience and animal research that renal hypoxia may lead to temporary or permanent renal failure, the severity being dependent largely on the duration and grade of the hypoxia. The medulla is more susceptible to hypoxic injury than the cortex because approximately 90% of the renal blood flow supplies the cortex. Various methods have been applied to evaluate renal perfusion in both experimental and clinical settings, including magnetic resonance imaging, computed tomography, laser Doppler, and contrast-enhanced ultrasound (CEUS). PURPOSE The aim of this study was to evaluate changes in overall and regional renal perfusion with CEUS in response to global hypoxia. MATERIAL AND METHODS Twelve newborn anesthetized piglets were exposed to general hypoxia with a fraction of inspired oxygen of 8% of 30 minutes duration. Resuscitation was performed with either 100% oxygen (n = 6) or air (21% oxygen) (n = 6) for 30 minutes followed by 7 hours of reoxygenation with air. Before, during, and after hypoxia, the left kidney was examined with CEUS using 0.2 mL IV of SonoVue followed by 2 mL saline flush. Five additional piglets served as controls. The kidney was examined using a 9-MHz linear transducer with low mechanical index (0.21) and pulse inversion contrast program. One region of interest was drawn in the renal cortex and 1 in the medulla to obtain the corresponding time intensity curves (TICs). From these curves, the peak intensity (PI), time to peak (TTP), upslope of the curve, area under the curve, and mean transit time (MTT) were recorded. Also, the renal arteriovenous transit time (AVTT) was registered. The resistance index (RI) was repeatedly measured in the renal artery. Contrast-enhanced ultrasound was repeated at regular intervals until the animals were sacrificed 8 hours after the hypoxic period. RESULTS In the group of 12 piglets subjected to hypoxia, RI increased from 0.69 ± 0.08 at baseline to 0.99 ± 0.09 during hypoxia (P < 0.01), indicating severe general renal vasoconstriction. The AVTT increased from 2.6 ± 0.5 seconds at baseline to 6.7 ± 2.8 seconds during hypoxia (P < 0.001). The PI in the cortex decreased from a mean value of 38.6 ± 6.1 dB at baseline to 30.3 ± 9.7 dB during hypoxia (P < 0.05). In the medulla, only a minor, nonsignificant reduction in PI was observed during hypoxia. In the medulla, TTP and MTT increased from 6.4 ± 1.5 and 9.2 ± 1.7 seconds at baseline to 14.6 ± 8.4 seconds (P < 0.01) and 15.2 ± 5.6 seconds (P < 0.01), respectively, during hypoxia. In the cortex, no statistically significant changes in TTP or MTT were observed during hypoxia. A return to near-baseline values was observed for TTP, PI in both the medulla and cortex, as well as for RI and AVTT within 1 to 3 hours after hypoxia, and they remained relatively constant for the duration of the experiment.Less than 1 hour after the hypoxia, PI both in the cortex and the medulla was significantly higher in the group resuscitated with air than in the group resuscitated with 100% oxygen, 36.0 ± 4.3 versus 27.2 ± 2.2 dB (P < 0.05) and 33.3 ± 8.2 versus 21.1 ± 2.0 dB (P < 0.01), respectively. CONCLUSION Global hypoxia induced changes in overall and regional renal perfusion detectable with CEUS. Cortical and medullary flows were affected differently by hypoxia; a strong increase in medullary TTP and MTT was observed, indicating a reduction in medullary blood flow velocity. In the cortex, a significant reduction in PI was found, probably because of a reduction in cortical blood volume. A faster recovery of both medullary and cortical PI in the group resuscitated with air could indicate that air might be more beneficial for renal perfusion than hyperoxia during resuscitation after renal hypoxia.
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Use of Dual-Source Computed Tomography to Evaluate Renal Cortical Perfusion in Patients With Essential Hypertension Without Diabetes: Preliminary Results. J Comput Assist Tomogr 2015; 39:473-8. [PMID: 25756803 DOI: 10.1097/rct.0000000000000230] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To assess renal cortical perfusion parameter changes using computed tomography (CT) renal perfusion examination in patients with essential hypertension (EH), especially those with EH-related target organ damage (TOD), and to correlate renal perfusion parameters with clinical and laboratory data. METHODS Consecutive patients with EH (without exclusion criteria) and healthy controls underwent 128-slice dual-source CT perfusion imaging. Quantitative perfusion analysis of renal cortex parameters [blood flow (BF), blood volume, time to peak, and mean transit time] was performed. RESULTS Ninety-one participants (60 patients with EH, 31 healthy controls) underwent renal perfusion CT imaging, and 84 participants (92.3%) were eligible for perfusion analysis. The BF values were lower in patients with EH than that in controls. Blood flow was correlated with age (P < 0.01), duration of hypertension (P < 0.01), estimated glomerular filtration rate (eGFR; P < 0.01), pulse pressure (P < 0.05), and body mass index (BMI; P < 0.05). Duration of hypertension, eGFR, and BMI were independently associated with BF. No parameter differed between control subjects and those with EH but not. Blood flow was lower in patients with TOD than in control subjects (P < 0.01), but no other parameter differed. Blood flow was lower (P < 0.01) and mean transit time and time to peak were higher (P < 0.05) in the TOD than that in the non-TOD group. CONCLUSIONS Essential hypertension, especially EH-related TOD, alters renal cortical perfusion parameters, especially BF. Four-dimensional spiral CT renal perfusion examination showed that duration of hypertension, eGFR, and BMI were independently associated with decreased BF.
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Ogul H, Bayraktutan U, Kizrak Y, Pirimoglu B, Yuceler Z, Sagsoz ME, Yilmaz O, Aydinli B, Ozturk G, Kantarci M. Abdominal perfusion computed tomography. Eurasian J Med 2015; 45:50-7. [PMID: 25610249 DOI: 10.5152/eajm.2013.09] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Accepted: 06/16/2012] [Indexed: 01/03/2023] Open
Abstract
The purpose of this article is to provide an up to date review on the spectrum of applications of perfusion computed tomography (CT) in the abdomen. New imaging techniques have been developed with the objective of obtaining a structural and functional analysis of different organs. Recently, perfusion CT has aroused the interest of many researchers who are studying the applicability of imaging modalities in the evaluation of abdominal organs and diseases. Per-fusion CT enables fast, non-invasive imaging of the tumor vascular physiology. Moreover, it can act as an in vivo biomarker of tumor-related angiogenesis.
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Affiliation(s)
- Hayri Ogul
- Department of Radiology, School of Medicine, Atatürk University, Erzurum, Turkey
| | | | - Yesim Kizrak
- Department of Radiology, School of Medicine, Atatürk University, Erzurum, Turkey
| | - Berhan Pirimoglu
- Department of Radiology, School of Medicine, Atatürk University, Erzurum, Turkey
| | - Zeynep Yuceler
- Department of Radiology, School of Medicine, Atatürk University, Erzurum, Turkey
| | - M Erdem Sagsoz
- Department of Biophysics, School of Medicine, Atatürk University, Erzurum, Turkey
| | - Omer Yilmaz
- Department of General Surgery, School of Medicine, Atatürk University, Erzurum, Turkey
| | - Bulent Aydinli
- Department of General Surgery, School of Medicine, Atatürk University, Erzurum, Turkey
| | - Gurkan Ozturk
- Department of General Surgery, School of Medicine, Atatürk University, Erzurum, Turkey
| | - Mecit Kantarci
- Department of Radiology, School of Medicine, Atatürk University, Erzurum, Turkey
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Grenier N, Cornelis F, Le Bras Y, Rigou G, Boutault J, Bouzgarrou M. Perfusion imaging in renal diseases. Diagn Interv Imaging 2013; 94:1313-22. [DOI: 10.1016/j.diii.2013.08.018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Helck A, Wessely M, Notohamiprodjo M, Schönermarck U, Klotz E, Fischereder M, Schön F, Nikolaou K, Clevert DA, Reiser M, Becker C. CT perfusion technique for assessment of early kidney allograft dysfunction: preliminary results. Eur Radiol 2013; 23:2475-81. [DOI: 10.1007/s00330-013-2862-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 03/12/2013] [Accepted: 03/30/2013] [Indexed: 10/26/2022]
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Ichikawa S, Motosugi U, Ichikawa T, Sano K, Morisaka H, Araki T. Intravoxel incoherent motion imaging of the kidney: alterations in diffusion and perfusion in patients with renal dysfunction. Magn Reson Imaging 2013; 31:414-7. [PMID: 23102943 DOI: 10.1016/j.mri.2012.08.004] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2012] [Revised: 07/11/2012] [Accepted: 08/30/2012] [Indexed: 01/10/2023]
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Rognant N, Bacchetta J, Juillard L. [Comparison of methods estimating a quantitative parameter: evaluation of the agreement]. Nephrol Ther 2013; 9:92-7. [PMID: 23415929 DOI: 10.1016/j.nephro.2012.09.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 09/03/2012] [Accepted: 09/03/2012] [Indexed: 11/28/2022]
Abstract
Many quantitative clinical, biological and radiological parameters are useful in medicine for guiding diagnosis and therapy. The nephrologists use such parameters on a daily basis, particularly to assess renal function. In order to use the measurement methods of these parameters in clinical practice, it is mandatory to establish the agreement of the values provided, comparatively to the value obtained by using the reference measurement method of this parameter. This review details the methodology for the validation of methods for estimating quantitative parameters.
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Affiliation(s)
- Nicolas Rognant
- Service de néphrologie, hôpital Édouard-Herriot, hospices civils de Lyon, 5, place d'Arsonval, 69437 Lyon cedex 03, France.
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CT Dynamics: The Shift from Morphology to Function. CURRENT RADIOLOGY REPORTS 2013. [DOI: 10.1007/s40134-012-0004-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Apport de la tomodensitométrie par rayons X dans l’évaluation de la performance rénale. Nephrol Ther 2012; 8:206-11. [DOI: 10.1016/j.nephro.2011.07.413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Revised: 06/20/2011] [Accepted: 07/17/2011] [Indexed: 11/16/2022]
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