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Intravoxel Incoherent Motion-Diffusion-Weighted MRI for Investigation of Delayed Graft Function Immediately after Kidney Transplantation. BIOMED RESEARCH INTERNATIONAL 2022; 2022:2832996. [PMID: 36303584 PMCID: PMC9596237 DOI: 10.1155/2022/2832996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/02/2022] [Accepted: 09/12/2022] [Indexed: 11/17/2022]
Abstract
Purpose A non-invasive way of assessing post-transplant renal graft function has been needed. This study aimed to assess the micro-structural and micro-functional status of graft kidneys by using intravoxel incoherent motion- (IVIM-) diffusion-weighted imaging (DWI) to investigate delayed graft function (DGF) immediately after transplantation. Method A prospective study was conducted on 37 patients, 14 with early graft function (EGF) and 23 with DGF (9 with complication, 14 without) who underwent IVIM-DWI, most often within 1-7 days after kidney transplantation. A total of 37 cases were collected and all the participants have been well-informed and signed their consents. In addition, the study conducted in this paper was approved by the Ethics Committee of Clinical Research, Taichung Veterans General Hospital (IRB number: CE14065). Using biexponential analysis of slow diffusion coefficient (Dslow), fast diffusion coefficient (Dfast), and perfusion fraction was performed. The apparent diffusion coefficient (ADC) was calculated by use of a monoexponential model. All parameters were measured from three different regions-of-interest (ROI), covering the entire renal parenchyma, cortex, and medulla. Results Dslow, perfusion fraction, and ADC were significantly higher in patients with EGF than DGF (all p values values <0.001). Especially, ADC measured from ROI covering the entire kidney parenchyma had the best cut-off value (1.93μm2/msec) with the highest area under the receiver operating characteristic curve (AUC 0.943) in differentiating EGF from DGF. For analysis of pair-wise differences, only the perfusion fraction values, measured from the ROI covering the renal cortex, were significantly higher in 14 DGF patients with no complications than in the 9 DGF patients with complications, with the best cut-off value of 12.3% and the AUC of 0.844. Conclusion Noninvasive IVIM-DWI reliably differentiates DGF from EGF after kidney transplantation, and it may aid in identifying posttransplant complications and indications for renal biopsy.
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Dillman JR, Benoit SW, Gandhi DB, Trout AT, Tkach JA, VandenHeuvel K, Devarajan P. Multiparametric quantitative renal MRI in children and young adults: comparison between healthy individuals and patients with chronic kidney disease. Abdom Radiol (NY) 2022; 47:1840-1852. [PMID: 35237897 DOI: 10.1007/s00261-022-03456-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/11/2022] [Accepted: 02/14/2022] [Indexed: 11/26/2022]
Abstract
PURPOSE Multiparametric quantitative renal MRI may provide noninvasive radiologic biomarkers of chronic kidney disease (CKD) based on investigations in animal models and adults. We aimed to (1) obtain normative multiparametric quantitative MRI data from the kidneys of healthy children and young adults, (2) compare MRI measurements between healthy control participants and patients with CKD, and (3) determine if MRI measurements correlate with clinical and laboratory data as well as histology. METHODS This was a prospective, case-control study of 20 healthy controls and 12 CKD patients who underwent percutaneous renal biopsy ranging from 12 to 23 years of age between October 2018 and March 2020. Kidney function was documented and pathology assessed for fibrosis/inflammation. Utilizing a field strength of 1.5T, we examined renal T1, T2, and T2* relaxation mapping, MR elastography (MRE), and diffusion-weighted imaging (DWI). A single analyst made all manual measurements for quantitative MRI pulse sequences. Independent measurements from cortex, medulla, and whole kidney were obtained by drawing regions of interest on single slices from the upper, mid, and lower kidney. A weighted average was calculated for each kidney; if two kidneys, the right and left were averaged. Continuous variables were compared with Mann-Whitney U test; bivariate relationships were assessed using Spearman rank-order correlation. RESULTS Median estimated glomerular filtration rate (eGFR) was 112.3 ml/min/1.73 m2 in controls (n = 20, 10 females) and 55.0 ml/min/m2 in CKD patients (n = 12, 2 females) (p < 0.0001). Whole kidney (1333 vs. 1291 ms; p = 0.018) and cortical (1212 vs 1137 ms; p < 0.0001) T1 values were higher in CKD patients. Cortical T1 values correlated with eGFR (rho = - 0.62; p = 0.0003) and cystatin C (rho = 0.58; p = 0.0007). Whole kidney (1.87 vs. 2.02 10-3 mm2/s; p = 0.007), cortical (1.89 vs. 2.04 10-3 mm2/s; p = 0.008), and medullary (1.87 vs. 1.98 10-3 mm2/s; p = 0.0095) DWI apparent diffusion coefficients (ADC) were lower in CKD patients. Whole kidney ADC correlated with eGFR (rho = 0.45; p = 0.012) and cystatin C (rho = - 0.46; p = 0.009). Cortical histologic inflammation correlated with DWI ADC (rho = - 0.71; p = 0.011). CONCLUSION Renal T1 relaxation and DWI ADC measurements differ between pediatric healthy controls and CKD patients, correlate with laboratory markers of CKD, and may have histologic correlates.
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Affiliation(s)
- Jonathan R Dillman
- Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45244, USA.
- Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
| | - Stefanie W Benoit
- Division of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Deep B Gandhi
- Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45244, USA
| | - Andrew T Trout
- Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45244, USA
- Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Jean A Tkach
- Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45244, USA
- Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Katherine VandenHeuvel
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
- Division of Pathology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Prasad Devarajan
- Division of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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Diffusion-Weighted MRI in the Genitourinary System. J Clin Med 2022; 11:jcm11071921. [PMID: 35407528 PMCID: PMC9000195 DOI: 10.3390/jcm11071921] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 03/25/2022] [Accepted: 03/28/2022] [Indexed: 12/12/2022] Open
Abstract
Diffusion weighted imaging (DWI) constitutes a major functional parameter performed in Magnetic Resonance Imaging (MRI). The DW sequence is performed by acquiring a set of native images described by their b-values, each b-value representing the strength of the diffusion MR gradients specific to that sequence. By fitting the data with models describing the motion of water in tissue, an apparent diffusion coefficient (ADC) map is built and allows the assessment of water mobility inside the tissue. The high cellularity of tumors restricts the water diffusion and decreases the value of ADC within tumors, which makes them appear hypointense on ADC maps. The role of this sequence now largely exceeds its first clinical apparitions in neuroimaging, whereby the method helped diagnose the early phases of cerebral ischemic stroke. The applications extend to whole-body imaging for both neoplastic and non-neoplastic diseases. This review emphasizes the integration of DWI in the genitourinary system imaging by outlining the sequence's usage in female pelvis, prostate, bladder, penis, testis and kidney MRI. In gynecologic imaging, DWI is an essential sequence for the characterization of cervix tumors and endometrial carcinomas, as well as to differentiate between leiomyosarcoma and benign leiomyoma of the uterus. In ovarian epithelial neoplasms, DWI provides key information for the characterization of solid components in heterogeneous complex ovarian masses. In prostate imaging, DWI became an essential part of multi-parametric Magnetic Resonance Imaging (mpMRI) to detect prostate cancer. The Prostate Imaging-Reporting and Data System (PI-RADS) scoring the probability of significant prostate tumors has significantly contributed to this success. Its contribution has established mpMRI as a mandatory examination for the planning of prostate biopsies and radical prostatectomy. Following a similar approach, DWI was included in multiparametric protocols for the bladder and the testis. In renal imaging, DWI is not able to robustly differentiate between malignant and benign renal tumors but may be helpful to characterize tumor subtypes, including clear-cell and non-clear-cell renal carcinomas or low-fat angiomyolipomas. One of the most promising developments of renal DWI is the estimation of renal fibrosis in chronic kidney disease (CKD) patients. In conclusion, DWI constitutes a major advancement in genitourinary imaging with a central role in decision algorithms in the female pelvis and prostate cancer, now allowing promising applications in renal imaging or in the bladder and testicular mpMRI.
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Diffusion-Weighted Imaging and Mapping of T1 and T2 Relaxation Time for Evaluation of Chronic Renal Allograft Rejection in a Translational Mouse Model. J Clin Med 2021; 10:jcm10194318. [PMID: 34640336 PMCID: PMC8509284 DOI: 10.3390/jcm10194318] [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: 08/24/2021] [Revised: 09/16/2021] [Accepted: 09/20/2021] [Indexed: 12/16/2022] Open
Abstract
We hypothesized that multiparametric MRI is able to non-invasively assess, characterize and monitor renal allograft pathology in a translational mouse model of chronic allograft rejection. Chronic rejection was induced by allogenic kidney transplantation (ktx) of BALB/c-kidneys into C57BL/6-mice (n = 23). Animals after isogenic ktx (n = 18) and non-transplanted healthy animals (n = 22) served as controls. MRI sequences (7T) were acquired 3 and 6 weeks after ktx and quantitative T1, T2 and apparent diffusion coefficient (ADC) maps were calculated. In addition, in a subset of animals, histological changes after ktx were evaluated. Chronic rejection was associated with a significant prolongation of T1 time compared to isogenic ktx 3 (1965 ± 53 vs. 1457 ± 52 ms, p < 0.001) and 6 weeks after surgery (1899 ± 79 vs. 1393 ± 51 ms, p < 0.001). While mean T2 times and ADC were not significantly different between allogenic and isogenic kidney grafts, histogram-based analysis of ADC revealed significantly increased tissue heterogeneity in allografts at both time points (standard derivation/entropy/interquartile range, p < 0.05). Correspondingly, histological analysis showed severe inflammation, graft fibrosis and tissue heterogeneity in allogenic but not in isogenic kidney grafts. In conclusion, renal diffusion weighted imaging and mapping of T2 and T1 relaxation times enable detection of chronic renal allograft rejection in mice. The combined quantitative assessment of mean values and histograms provides non-invasive information of chronic changes in renal grafts and allows longitudinal monitoring.
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Ko SF, Yip HK, Zhen YY, Hung CC, Lee CC, Huang CC, Ng SH, Chen YL, Lin JW. Renal Damages in Deoxycorticosterone Acetate-Salt Hypertensive Rats: Assessment with Diffusion Tensor Imaging and T2-mapping. Mol Imaging Biol 2021; 22:94-104. [PMID: 31065896 DOI: 10.1007/s11307-019-01364-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
PURPOSE This study aimed to investigate the feasibility of diffusion tensor imaging (DTI) and T2-mapping to assess temporal renal damage in deoxycorticosterone acetate-salt (DOCA-salt) hypertensive rats and compare the results with histopathologic and immunohistochemical findings. PROCEDURES After baseline renal magnetic resonance imaging (MRI), 24 out of 30 uninephrectomized Sprague-Dawley rats with DOCA-salt-induced hypertension were divided equally into four groups. Group 1 had renal MRI at weeks 2, 4, 6, and 8, and groups 2, 3, and 4 had MRI at weeks 2, 4, and 6, respectively. The remaining 6 rats were used as sham controls. The renal cortex and outer and inner stripes of the outer medulla were examined over time using fractional anisotropy (FA), apparent diffusion coefficient (ADC), and T2-mapping, and the results were compared with baseline values. The degree of glomerular and tubular injury, endothelial cell thickening, hyaline arteriolosclerosis, macrophage infiltration, microcyst formation, and fibrosis in different zones at different time points in the DOCA-salt rats were compared with controls. RESULTS Compared with baseline values, DOCA-salt rats demonstrated a significant decrease in renal cortical FA from week 4 to week 8 (0.244 ± 0.015 vs 0.172 ± 0.014-0.150 ± 0.016, P = 0.018-0.002), corresponding to significantly more glomerular damage, arteriolosclerosis, macrophage infiltration, and fibrosis. The DOCA-salt rats had significantly increased cortical ADC and T2 values at weeks 6 and 8 (1.778 ± 0.051 × 10-3 mm2/s vs 1.872 ± 0.058-1.917 ± 0.066 × 10-3 mm2/s; 93.7 ± 4.9 ms vs 98.0 ± 2.9-100.7 ± 4.0 ms, respectively, all P < 0.05), consistent with excessively fluid-filled microcysts (aquaporin-2+). Despite DOCA-salt rats harbored markedly increased fibrosis in outer and inner stripes of the outer medulla at weeks 6 and 8, only nonsignificant decreases in FA were observed in comparison with the controls suggesting that only limited microstructural changes were present. CONCLUSIONS Renal cortical FA is useful for the early detection and monitoring of renal damage in DOCA-salt hypertensive rats.
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Affiliation(s)
- Sheung-Fat Ko
- Department of Radiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, 123 Ta-Pei Road, Niao-Sung District, Kaohsiung, 833, Taiwan.
| | - Hon-Kan Yip
- Department of Cardiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan.,Center for Translational Researches in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Yen-Yi Zhen
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chi-Chih Hung
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chen-Chang Lee
- Department of Radiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, 123 Ta-Pei Road, Niao-Sung District, Kaohsiung, 833, Taiwan
| | - Chung-Cheng Huang
- Department of Radiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, 123 Ta-Pei Road, Niao-Sung District, Kaohsiung, 833, Taiwan
| | - Shu-Hang Ng
- Department of Radiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, 123 Ta-Pei Road, Niao-Sung District, Kaohsiung, 833, Taiwan
| | - Yi-Ling Chen
- Department of Radiology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, 123 Ta-Pei Road, Niao-Sung District, Kaohsiung, 833, Taiwan.,Center for Translational Researches in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Jui-Wei Lin
- Department of Pathology, Kaohsiung Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Kaohsiung, Taiwan
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Gopireddy DR, Mahmoud H, Baig S, Le R, Bhosale P, Lall C. "Renal emergencies: a comprehensive pictorial review with MR imaging". Emerg Radiol 2020; 28:373-388. [PMID: 32974867 DOI: 10.1007/s10140-020-01852-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 09/17/2020] [Indexed: 12/11/2022]
Abstract
Superior soft-tissue contrast and high sensitivity of magnetic resonance imaging (MRI) for detecting and characterizing disease may provide an expanded role in acute abdominal and pelvic imaging. Although MRI has traditionally not been exploited in acute care settings, commonly used in biliary obstruction and during pregnancy, there are several conditions in which MRI can go above and beyond other modalities in diagnosis, characterization, and providing functional and prognostic information. In this manuscript, we highlight how MRI can help in further assessment and characterization of acute renal emergencies. Currently, renal emergencies are predominantly evaluated with ultrasound (US) or computed tomography (CT) scanning. US may be limited by various patient factors and technologist experience while CT imaging with intravenous contrast administration can further compromise renal function. With the advent of rapid, robust non-contrast MRI, and magnetic resonance angiography (MRA) imaging studies with short scan times, free-breathing techniques, and lack of ionization radiation, the utility of MRI for renal evaluation might be superior to CT not only in diagnosing an emergent renal process but also by providing functional and prognostic information. This review outlines the clinical manifestations and the key imaging findings for acute renal processes including acute renal infarction, hemorrhage, and renal obstruction, among other entities, to highlight the added value of MRI in evaluating the finer nuances in acute renal emergencies.
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Affiliation(s)
- Dheeraj Reddy Gopireddy
- Department of Radiology, UF College of Medicine-Jacksonville, 2nd Floor, Clinical Center, 655 West 8th Street, C90, Jacksonville, FL, 33209, USA.
| | - Hagar Mahmoud
- Department of Diagnostic Radiology, the University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Saif Baig
- Imaging Informatics and Artificial Intelligence, University of Florida, College Medicine, Gainesville, FL, USA
| | - Rebecca Le
- Jacksonville Center for Clinical Research, University of Florida, Gainesville, FL, USA
| | - Priya Bhosale
- Department of Diagnostic Radiology, the University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Chandana Lall
- Department of Radiology, UF College of Medicine-Jacksonville, 2nd Floor, Clinical Center, 655 West 8th Street, C90, Jacksonville, FL, 33209, USA
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Al-Qahtani AA, Alenzi AAS, Jandani R, Shoukat Ali A. Early Projection of Kidney Allograft Rejection Through Deep Learning: A Way Forward. EXP CLIN TRANSPLANT 2020; 19:176-177. [PMID: 32967601 DOI: 10.6002/ect.2020.0238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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S. T, Arunachalam VK, R. R, R. S. Role of Diffusion Tensor Imaging in Functional Assessment of Transplant Kidneys at 3-Tesla MRI. JOURNAL OF GASTROINTESTINAL AND ABDOMINAL RADIOLOGY 2020. [DOI: 10.1055/s-0040-1709084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Abstract
Objectives The main purpose of this article is to measure the fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of cortex and medulla of renal allograft using 3-Tesla diffusion tensor imaging (DTI) in renal transplant patients with normal and graft dysfunction and to assess the correlation between diffusion tensor parameters (ADC and FA) and the estimated glomerular filtration rate (eGFR) value.
Materials and Methods Fifty renal transplant recipients who received either living or cadaveric renal allografts were included in the study. Blood samples for serum creatinine and eGFR value were taken on the same day prior to the magnetic resonance study and the patients were assigned to three groups (A, B, C) according to allograft function (eGFR levels). The mean ADC and FA values of the cortex/medulla in upper, mid, and lower poles were calculated from the DTI sequence. Statistical analysis was performed using paired sample Student’s t-test and one-way analysis of variance test.
Results The mean ADC values of the cortex were higher than the medulla that was statistically significant. However, the mean FA values were significantly higher in the medulla than the cortex. Mean ADCs and FA of the renal cortex and medulla were significantly higher in group A patients with normal renal function than in group B and C with poor renal functions. The corticomedullary difference in the FA values was more in group A. However, this difference was lower in group B and more so in group C.
Conclusion ADC and FA values in the renal cortex and medulla exhibit a good correlation with allograft function and were significantly lower in transplants with dysfunction than those with good function. FA values appear to be more sensitive than eGFR and ADC for detection of early pathological changes in the graft dysfunction.
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Affiliation(s)
- Thambidurai S.
- Department of Radiology, Kovai Medical Center and Hospital, Coimbatore, Tamil Nadu, India
| | | | - Rupa R.
- Department of Radiology, Kovai Medical Center and Hospital, Coimbatore, Tamil Nadu, India
| | - Sriman R.
- Department of Radiology, Kovai Medical Center and Hospital, Coimbatore, Tamil Nadu, India
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Shehata M, Shalaby A, Switala AE, El-Baz M, Ghazal M, Fraiwan L, Khalil A, El-Ghar MA, Badawy M, Bakr AM, Dwyer A, Elmaghraby A, Giridharan G, Keynton R, El-Baz A. A multimodal computer-aided diagnostic system for precise identification of renal allograft rejection: Preliminary results. Med Phys 2020; 47:2427-2440. [PMID: 32130734 DOI: 10.1002/mp.14109] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 02/18/2020] [Accepted: 02/18/2020] [Indexed: 12/26/2022] Open
Abstract
PURPOSE Early assessment of renal allograft function post-transplantation is crucial to minimize and control allograft rejection. Biopsy - the gold standard - is used only as a last resort due to its invasiveness, high cost, adverse events (e.g., bleeding, infection, etc.), and the time for reporting. To overcome these limitations, a renal computer-assisted diagnostic (Renal-CAD) system was developed to assess kidney transplant function. METHODS The developed Renal-CAD system integrates data collected from two image-based sources and two clinical-based sources to assess renal transplant function. The imaging sources were the apparent diffusion coefficients (ADCs) extracted from 47 diffusion-weighted magnetic resonance imaging (DW-MRI) scans at 11 different b-values (b0, b50, b100, ..., b1000 s/mm 2 ), and the transverse relaxation rate (R2*) extracted from 30 blood oxygen level-dependent MRI (BOLD-MRI) scans at 5 different echo times (TEs = 2, 7, 12, 17, and 22 ms). Serum creatinine (SCr) and creatinine clearance (CrCl) were the clinical sources for kidney function evaluation. The Renal-CAD system initially performed kidney segmentation using the level-set method, followed by estimation of the ADCs from DW-MRIs and the R2* from BOLD-MRIs. ADCs and R2* estimates from 30 subjects that have both types of scans were integrated with their associated SCr and CrCl. The integrated biomarkers were then used as our discriminatory features to train and test a deep learning-based classifier, namely stacked autoencoders (SAEs) to differentiate non-rejection (NR) from acute rejection (AR) renal transplants. RESULTS Using a leave-one-subject-out cross-validation approach along with SAEs, the Renal-CAD system demonstrated 93.3% accuracy, 90.0% sensitivity, and 95.0% specificity in differentiating AR from NR. Robustness of the Renal-CAD system was also confirmed by the area under the curve value of 0.92. Using a stratified tenfold cross-validation approach, the Renal-CAD system demonstrated its reproducibility and robustness by a diagnostic accuracy of 86.7%, sensitivity of 80.0%, specificity of 90.0%, and AUC of 0.88. CONCLUSION The obtained results demonstrate the feasibility and efficacy of accurate, noninvasive identification of AR at an early stage using the Renal-CAD system.
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Affiliation(s)
- Mohamed Shehata
- BioImaging Lab, Department of Bioengineering, University of Louisville, Louisville, KY, 40208, USA
| | - Ahmed Shalaby
- BioImaging Lab, Department of Bioengineering, University of Louisville, Louisville, KY, 40208, USA
| | - Andrew E Switala
- BioImaging Lab, Department of Bioengineering, University of Louisville, Louisville, KY, 40208, USA
| | - Maryam El-Baz
- BioImaging Lab, Department of Bioengineering, University of Louisville, Louisville, KY, 40208, USA
| | - Mohammed Ghazal
- Electrical and Computer Engineering Department, Abu Dhabi University, Abu Dhabi, 59911, UAE
| | - Luay Fraiwan
- Electrical and Computer Engineering Department, Abu Dhabi University, Abu Dhabi, 59911, UAE
| | - Ashraf Khalil
- Computer Science and Information Technology Department, Abu Dhabi University, Abu Dhabi, 59911, UAE
| | - Mohamed Abou El-Ghar
- Urology and Nephrology Center, Radiology Department, Mansoura University, Mansoura, 35516, Egypt
| | - Mohamed Badawy
- Urology and Nephrology Center, Radiology Department, Mansoura University, Mansoura, 35516, Egypt
| | - Ashraf M Bakr
- Pediatric Nephrology Unit, Mansoura University Children's Hospital, University of Mansoura, Mansoura, 35516, Egypt
| | - Amy Dwyer
- Kidney Disease Program, University of Louisville, Louisville, KY, 40202, USA
| | - Adel Elmaghraby
- Computer Engineering and Computer Science Department, University of Louisville, Louisville, KY, 40208, USA
| | | | - Robert Keynton
- Department of Bioengineering, University of Louisville, Louisville, KY, 40208, USA
| | - Ayman El-Baz
- Department of Bioengineering, University of Louisville, Louisville, KY, 40208, USA.,200 E Shipp Ave, Lutz 390 Hall, Room 419, Louisville, KY, 40208, USA
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Schutter R, Lantinga VA, Borra RJH, Moers C. MRI for diagnosis of post-renal transplant complications: current state-of-the-art and future perspectives. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2019; 33:49-61. [PMID: 31879853 DOI: 10.1007/s10334-019-00813-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 10/27/2019] [Accepted: 11/30/2019] [Indexed: 02/07/2023]
Abstract
Kidney transplantation has developed into a widespread procedure to treat end stage renal failure, with transplantation results improving over the years. Postoperative complications have decreased over the past decades, but are still an important cause of morbidity and mortality. Early accurate diagnosis and treatment is the key to prevent renal allograft impairment or even graft loss. Ideally, a diagnostic tool should be able to detect post-transplant renal dysfunction, differentiate between the different causes and monitor renal function during and after therapeutic interventions. Non-invasive imaging modalities for diagnostic purposes show promising results. Magnetic resonance imaging (MRI) techniques have a number of advantages, such as the lack of ionizing radiation and the possibility to obtain relevant tissue information without contrast, reducing the risk of contrast-induced nephrotoxicity. However, most techniques still lack the specificity to distinguish different types of parenchymal diseases. Despite some promising outcomes, MRI is still barely used in the post-transplantation diagnostic process. The aim of this review is to survey the current literature on the relevance and clinical applicability of diagnostic MRI modalities for the detection of various types of complications after kidney transplantation.
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Affiliation(s)
- Rianne Schutter
- University Medical Center Groningen, University of Groningen, Groningen, Netherlands.
| | - Veerle A Lantinga
- University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Ronald J H Borra
- University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Cyril Moers
- University Medical Center Groningen, University of Groningen, Groningen, Netherlands
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Shehata M, Shalaby A, Ghazal M, Abou El-Ghar M, Badawy MA, Beache G, Dwyer A, El-Melegy M, Giridharan G, Keynton R, El-Baz A. EARLY ASSESSMENT OF RENAL TRANSPLANTS USING BOLD-MRI: PROMISING RESULTS. PROCEEDINGS. INTERNATIONAL CONFERENCE ON IMAGE PROCESSING 2019; 2019:1395-1399. [PMID: 34690556 DOI: 10.1109/icip.2019.8803042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Non-invasive evaluation of renal transplant function is essential to minimize and manage renal rejection. A computer-assisted diagnostic (CAD) system was developed to evaluate kidney function post-transplantation. The developed CAD system utilizes the amount of blood-oxygenation extracted from 3D (2D + time) blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) to estimate renal function. BOLD-MRI scans were acquired at five different echo-times (2, 7, 12, 17, and 22) ms from 15 transplant patients. The developed CAD system first segments kidneys using the level-sets method followed by estimation of the amount of deoxyhemoglobin, also known as apparent relaxation rate (R2*). These R2* estimates were used as discriminatory features (global features (mean R2*) and local features (pixel-wise R2*)) to train and test state-of-the-art machine learning classifiers to differentiate between non-rejection (NR) and acute renal rejection. Using a leave-one-out cross-validation approach along with an artificial neural network (ANN) classifier, the CAD system demonstrated 93.3% accuracy, 100% sensitivity, and 90% specificity in distinguishing AR from non-rejection . These preliminary results demonstrate the efficacy of the CAD system to detect renal allograft status non-invasively.
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Affiliation(s)
- M Shehata
- Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - A Shalaby
- Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - M Ghazal
- Electrical and Computer Engineering Department, Abu Dhabi University, Abu Dhabi, UAE.,Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - M Abou El-Ghar
- Radiology Department, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt
| | - M A Badawy
- Radiology Department, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt
| | - G Beache
- Radiology Department, University of Louisville, Louisville, KY, USA
| | - A Dwyer
- Kidney Disease Program, University of Louisville, Louisville, KY, USA
| | - M El-Melegy
- Department of Electrical Engineering, Assiut University, Assiut, Egypt
| | - G Giridharan
- Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - R Keynton
- Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - A El-Baz
- Bioengineering Department, University of Louisville, Louisville, KY, USA
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12
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Relationship of renal apparent diffusion coefficient and functional MR urography in children with pelvicalyceal dilation. Pediatr Radiol 2019; 49:1032-1041. [PMID: 31001665 DOI: 10.1007/s00247-019-04395-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 02/25/2019] [Accepted: 03/26/2019] [Indexed: 12/18/2022]
Abstract
OBJECTIVE The aim is to evaluate the age-related changes and relationship of renal apparent diffusion coefficient (ADC) against the morphological and functional changes detected by functional magnetic resonance urography (fMRU) in children with pelvicalyceal dilation, with suspected or known ureteropelvic junction obstruction. MATERIALS AND METHODS We retrospectively analyzed fMRUs with diffusion-weighted imaging (DWI) of the kidney in 35 subjects (25 males; median age: 7.1 years, range: 0.3-22.7 years) with 70 kidneys (40 with pelvicalyceal dilation and 30 with no pelvicalyceal dilation). Inclusion criteria were pelvicalyceal dilation, the absence of duplex kidneys and no ureteric dilation. DWI was performed with 3 diffusion gradient directions (b values = 0, 200, 500, 800 and 1,000 s/mm2). Metrics for fMRU included calyceal and renal transit times (CTT, RTT), time-to-peak (TTP), differential renal function based on volume (vDRF), Patlak number (pDRF) and combined volume and Patlak number (vpDRF). The grades of pelvicalyceal dilation, cortical thinning and corticomedullary differentiation were evaluated. The relationship between ADC values and the fMRU parameters was analyzed. RESULTS ADC increases with age in kidneys without pelvicalyceal dilation (R2=0.37, P<0.001). Renal ADC does not correlate with any of the morphological or fMRU parameters (P>0.07). The median ADC of kidneys without pelvicalyceal dilation was 3.73×10-3 mm2/s (range: 2.78-5.37×0-3 mm2/s) and the median ADC of kidneys with pelvicalyceal dilation was 3.82×10-3 mm2/s (range: 2.70-5.70×10-3 mm2/s). There was no correlation between ADC and the absolute differences of vDRF or pDRF (P>0.33). CONCLUSION Renal ADC does not correlate with morphological and functional results of fMRU changes in children with pelvicalyceal dilation due to suspected or known ureteropelvic junction obstruction.
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Köhnke R, Kentrup D, Schütte-Nütgen K, Schäfers M, Schnöckel U, Hoerr V, Reuter S. Update on imaging-based diagnosis of acute renal allograft rejection. AMERICAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING 2019; 9:110-126. [PMID: 31139495 PMCID: PMC6526365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Accepted: 04/12/2019] [Indexed: 06/09/2023]
Abstract
Kidney transplantation is the preferred treatment for patients with end-stage renal disease. Despite effective immunosuppressants, acute allograft rejections pose a major threat to graft survival. In early stages, acute rejections are still potentially reversible, and early detection is crucial to initiate the necessary treatment options and to prevent further graft dysfunction or even loss of the complete graft. Currently, invasive core needle biopsy is the reference standard to diagnose acute rejection. However, biopsies carry the risk of graft injuries and cannot be immediately performed on patients receiving anticoagulation drugs. Therefore, non-invasive assessment of the whole organ for specific and rapid detection of acute allograft rejection is desirable. We herein provide a review summarizing current imaging-based approaches for non-invasive diagnosis of acute renal allograft rejection.
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Affiliation(s)
- Richard Köhnke
- Department of Medicine, Division of General Internal Medicine, Nephrology and Rheumatology, University Hospital of Muenster48149 Muenster, Germany
| | - Dominik Kentrup
- Department of Medicine, Division of General Internal Medicine, Nephrology and Rheumatology, University Hospital of Muenster48149 Muenster, Germany
- Department of Medicine, Division of Nephrology, The University of Alabama at Birmingham (UAB)35294 Birmingham Alabama, US
| | - Katharina Schütte-Nütgen
- Department of Medicine, Division of General Internal Medicine, Nephrology and Rheumatology, University Hospital of Muenster48149 Muenster, Germany
| | - Michael Schäfers
- Department of Nuclear Medicine, University Hospital of Muenster48149 Muenster, Germany
- European Institute for Molecular Imaging, University of Muenster48140 Muenster, Germany
| | - Uta Schnöckel
- Department of Nuclear Medicine, University Hospital of Muenster48149 Muenster, Germany
| | - Verena Hoerr
- Department of Clinical Radiology, University Hospital of Muenster48149 Muenster, Germany
- Institute of Medical Microbiology, Jena University HospitalAm Klinikum 1, 07747 Jena, Germany
| | - Stefan Reuter
- Department of Medicine, Division of General Internal Medicine, Nephrology and Rheumatology, University Hospital of Muenster48149 Muenster, Germany
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14
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Abdeltawab H, Shehata M, Shalaby A, Khalifa F, Mahmoud A, El-Ghar MA, Dwyer AC, Ghazal M, Hajjdiab H, Keynton R, El-Baz A. A Novel CNN-Based CAD System for Early Assessment of Transplanted Kidney Dysfunction. Sci Rep 2019; 9:5948. [PMID: 30976081 PMCID: PMC6459833 DOI: 10.1038/s41598-019-42431-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2018] [Accepted: 03/29/2019] [Indexed: 12/30/2022] Open
Abstract
This paper introduces a deep-learning based computer-aided diagnostic (CAD) system for the early detection of acute renal transplant rejection. For noninvasive detection of kidney rejection at an early stage, the proposed CAD system is based on the fusion of both imaging markers and clinical biomarkers. The former are derived from diffusion-weighted magnetic resonance imaging (DW-MRI) by estimating the apparent diffusion coefficients (ADC) representing the perfusion of the blood and the diffusion of the water inside the transplanted kidney. The clinical biomarkers, namely: creatinine clearance (CrCl) and serum plasma creatinine (SPCr), are integrated into the proposed CAD system as kidney functionality indexes to enhance its diagnostic performance. The ADC maps are estimated for a user-defined region of interest (ROI) that encompasses the whole kidney. The estimated ADCs are fused with the clinical biomarkers and the fused data is then used as an input to train and test a convolutional neural network (CNN) based classifier. The CAD system is tested on DW-MRI scans collected from 56 subjects from geographically diverse populations and different scanner types/image collection protocols. The overall accuracy of the proposed system is 92.9% with 93.3% sensitivity and 92.3% specificity in distinguishing non-rejected kidney transplants from rejected ones. These results demonstrate the potential of the proposed system for a reliable non-invasive diagnosis of renal transplant status for any DW-MRI scans, regardless of the geographical differences and/or imaging protocol.
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Affiliation(s)
- Hisham Abdeltawab
- Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - Mohamed Shehata
- Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - Ahmed Shalaby
- Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - Fahmi Khalifa
- Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - Ali Mahmoud
- Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - Mohamed Abou El-Ghar
- Radiology Department, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt
| | - Amy C Dwyer
- Kidney Disease Program, University of Louisville, Louisville, KY, USA
| | - Mohammed Ghazal
- Bioengineering Department, University of Louisville, Louisville, KY, USA.,Electrical and Computer Engineering Department, Abu Dhabi University, Abu Dhabi, UAE
| | - Hassan Hajjdiab
- Electrical and Computer Engineering Department, Abu Dhabi University, Abu Dhabi, UAE
| | - Robert Keynton
- Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - Ayman El-Baz
- Bioengineering Department, University of Louisville, Louisville, KY, USA.
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15
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Ding J, Xing Z, Jiang Z, Zhou H, Di J, Chen J, Qiu J, Yu S, Zou L, Xing W. Evaluation of renal dysfunction using texture analysis based on DWI, BOLD, and susceptibility-weighted imaging. Eur Radiol 2018; 29:2293-2301. [PMID: 30560361 DOI: 10.1007/s00330-018-5911-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 10/24/2018] [Accepted: 11/23/2018] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To explore the value of texture analysis based on diffusion-weighted imaging (DWI), blood oxygen level-dependent MRI (BOLD), and susceptibility-weighted imaging (SWI) in evaluating renal dysfunction. METHODS Seventy-two patients (mean age 53.72 ± 13.46 years) underwent MRI consisting of DWI, BOLD, and SWI. According to their estimated glomerular filtration rate (eGFR), the patients were classified into either severe renal function impairment (sRI, eGFR < 30 mL/min/1.73 m2), non-severe renal function impairment (non-sRI, eGFR ≥ 30 mL/min/1.73 m2, and < 80 mL/min/1.73 m2), or control (CG, eGFR ≥ 80 mL/min/1.73 m2) groups. Thirteen texture features were extracted and then were analyzed to select the most valuable for discerning the three groups with each imaging method. A ROC curve was performed to compare the capacities of the features to differentiate non-sRI from sRI or CG. RESULTS Six features proved to be the most valuable for assessing renal dysfunction: 0.25QuantileDWI, 0.5QuantileDWI, HomogeneityDWI, EntropyBOLD, SkewnessSWI, and CorrelationSWI. Three features derived from DWI (0.25QuantileDWI, 0.5QuantileDWI, and HomogeneityDWI) were smaller in sRI than in non-sRI; EntropyBOLD and CorrelationSWI were smaller in non-sRI than in CG (p < 0.05). 0.25QuantileDWI, 0.5QuantileDWI, and HomogeneityDWI showed similar capacities for differentiating sRI from non-sRI. Similarly, EntropyBOLD and CorrelationSWI showed equal capacities for differentiating non-sRI from CG. CONCLUSION Texture analysis based on DWI, BOLD, and SWI can assist in assessing renal dysfunction, and texture features based on BOLD and SWI may be suitable for assessing renal dysfunction during early stages. KEY POINTS • Texture analysis based on MRI techniques allowed for assessing renal dysfunction. • Texture features based on BOLD and SWI, but not DWI, may be suitable for assessing renal function impairment during early stages. • SWI exhibited a similar capacity to BOLD for assessing renal dysfunction.
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Affiliation(s)
- Jiule Ding
- Department of Radiology, Third Affiliated Hospital of Soochow University, Changzhou, 213003, Jiangsu, China
| | - Zhaoyu Xing
- Department of Urology, Third Affiliated Hospital of Soochow University, Changzhou, 213003, Jiangsu, China
| | - Zhenxing Jiang
- Department of Radiology, Third Affiliated Hospital of Soochow University, Changzhou, 213003, Jiangsu, China
| | - Hua Zhou
- Department of Nephrology, Third Affiliated Hospital of Soochow University, Changzhou, 213003, Jiangsu, China
| | - Jia Di
- Department of Nephrology, Third Affiliated Hospital of Soochow University, Changzhou, 213003, Jiangsu, China
| | - Jie Chen
- Department of Radiology, Third Affiliated Hospital of Soochow University, Changzhou, 213003, Jiangsu, China
| | - Jianguo Qiu
- Department of Radiology, Third Affiliated Hospital of Soochow University, Changzhou, 213003, Jiangsu, China
| | - Shengnan Yu
- Department of Radiology, Third Affiliated Hospital of Soochow University, Changzhou, 213003, Jiangsu, China
| | - Liqiu Zou
- Department of Radiology, Shenzhen nanshan People's Hospital, Shenzhen University Health Science Center, Shenzhen, 518000, Guangdong, China
| | - Wei Xing
- Department of Radiology, Third Affiliated Hospital of Soochow University, Changzhou, 213003, Jiangsu, China.
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16
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Palmucci S, Mammino L, Caltabiano DC, Costanzo V, Foti PV, Mauro LA, Farina R, Profitta ME, Sinagra N, Ettorre GC, Veroux M, Basile A. Diffusion-MR in kidney transplant recipients: is diuretic stimulation a useful diagnostic tool for improving differentiation between functioning and non-functioning kidneys? Clin Imaging 2018; 53:97-104. [PMID: 30317137 DOI: 10.1016/j.clinimag.2018.10.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 08/27/2018] [Accepted: 10/01/2018] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To evaluate the effects of diuretic stimulation on Diffusion Weighted Imaging (DWI) and Diffusion Tensor Imaging (DTI) techniques in transplanted kidneys. METHODS 33 transplanted kidney recipients underwent DWI and DTI sequences before and after furosemide. Cortical and medullary Apparent Diffusion Coefficient (ADC) and Fractional Anisotropy (FA) values were calculated in transplanted kidneys. Patients were divided into two groups according to their estimated glomerular rate filtration (Group A ≥ 60 ml/min and Group B < 60 ml/min). Wilcoxon matched pairs signed rank test was applied to compare pre- and post-furosemide values. ADC and FA values were compared between the 2 groups using a Mann-Whitney U test. Receiver Operating Curves (ROC) analysis was performed to predict normal renal function. RESULTS Wilcoxon test revealed a statistically significant difference for all pre- and post- ADC and FA values in group B. For group A, a significant difference was found comparing pre- and post-medullary ADC and FA values (p = 0.0151 and p = 0.0054). In the comparison between group A and group B, cortical and medullary mean ADC values were significantly different before and after furosemide. With regard to medullary FA values, a significant difference was found between groups before and after diuretic stimulation (p respectively of 0.004 and 0.042). Comparing cortical FA mean values, no statistical difference was observed between groups before and after furosemide. The highest Area Under Curve values were reported for cortical ADC (0.878) and medullary ADC (0.863) before diuretic bolus. CONCLUSIONS In transplanted kidneys, furosemide did not improve the differentiation between normal and reduced function.
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Affiliation(s)
- Stefano Palmucci
- Department of Medical Surgical Sciences and Advanced Technologies - Radiology I Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, Catania 95123, Italy.
| | - Luca Mammino
- Department of Medical Surgical Sciences and Advanced Technologies - Radiology I Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, Catania 95123, Italy
| | - Daniele Carmelo Caltabiano
- Department of Medical Surgical Sciences and Advanced Technologies - Radiology I Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, Catania 95123, Italy
| | - Valeria Costanzo
- Department of Medical Surgical Sciences and Advanced Technologies - Radiology I Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, Catania 95123, Italy
| | - Pietro Valerio Foti
- Department of Medical Surgical Sciences and Advanced Technologies - Radiology I Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, Catania 95123, Italy
| | - Letizia Antonella Mauro
- Department of Medical Surgical Sciences and Advanced Technologies - Radiology I Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, Catania 95123, Italy
| | - Renato Farina
- Department of Medical Surgical Sciences and Advanced Technologies - Radiology I Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, Catania 95123, Italy
| | - Maria Elena Profitta
- Department of Medical Surgical Sciences and Advanced Technologies - Radiology I Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, Catania 95123, Italy
| | - Nunziata Sinagra
- Vascular Surgery Unit - University Hospital "Policlinico-Vittorio Emanuele", 95123 Catania, Italy
| | | | - Massimiliano Veroux
- Department of Medical Surgical Sciences and Advanced Technologies - Vascular Surgery and Organ Transplant Unit, University Hospital "Policlinico-Vittorio Emanuele", 95123 Catania, Italy
| | - Antonio Basile
- Department of Medical Surgical Sciences and Advanced Technologies - Radiology I Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, Catania 95123, Italy
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17
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Caroli A, Schneider M, Friedli I, Ljimani A, De Seigneux S, Boor P, Gullapudi L, Kazmi I, Mendichovszky IA, Notohamiprodjo M, Selby NM, Thoeny HC, Grenier N, Vallée JP. Diffusion-weighted magnetic resonance imaging to assess diffuse renal pathology: a systematic review and statement paper. Nephrol Dial Transplant 2018; 33:ii29-ii40. [PMID: 30137580 PMCID: PMC6106641 DOI: 10.1093/ndt/gfy163] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 05/02/2018] [Indexed: 12/26/2022] Open
Abstract
Diffusion-weighted magnetic resonance imaging (DWI) is a non-invasive method sensitive to local water motion in the tissue. As a tool to probe the microstructure, including the presence and potentially the degree of renal fibrosis, DWI has the potential to become an effective imaging biomarker. The aim of this review is to discuss the current status of renal DWI in diffuse renal diseases. DWI biomarkers can be classified in the following three main categories: (i) the apparent diffusion coefficient-an overall measure of water diffusion and microcirculation in the tissue; (ii) true diffusion, pseudodiffusion and flowing fraction-providing separate information on diffusion and perfusion or tubular flow; and (iii) fractional anisotropy-measuring the microstructural orientation. An overview of human studies applying renal DWI in diffuse pathologies is given, demonstrating not only the feasibility and intra-study reproducibility of DWI but also highlighting the need for standardization of methods, additional validation and qualification. The current and future role of renal DWI in clinical practice is reviewed, emphasizing its potential as a surrogate and monitoring biomarker for interstitial fibrosis in chronic kidney disease, as well as a surrogate biomarker for the inflammation in acute kidney diseases that may impact patient selection for renal biopsy in acute graft rejection. As part of the international COST (European Cooperation in Science and Technology) action PARENCHIMA (Magnetic Resonance Imaging Biomarkers for Chronic Kidney Disease), aimed at eliminating the barriers to the clinical use of functional renal magnetic resonance imaging, this article provides practical recommendations for future design of clinical studies and the use of renal DWI in clinical practice.
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Affiliation(s)
- Anna Caroli
- Medical Imaging Unit, Bioengineering Department, IRCCS Istituto di Ricerche Farmacologiche Mario Negri, Bergamo, Italy
| | - Moritz Schneider
- Department of Radiology, Ludwig-Maximilians-University Hospital Munich, Munich, Germany
- Comprehensive Pneumology Center, German Center for Lung Research, Munich, Germany
| | - Iris Friedli
- Division of Radiology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland
| | - Alexandra Ljimani
- Department of Diagnostic and Interventional Radiology, Medical Faculty, University Dusseldorf, Dusseldorf, Germany
| | - Sophie De Seigneux
- Service and Laboratory of Nephrology, Department of Internal Medicine Specialties and Department of Physiology and Metabolism, Geneva University Hospitals, University of Geneva, Geneva, Switzerland
| | - Peter Boor
- Institute of Pathology and Division of Nephrology, RWTH University of Aachen, Aachen, Germany
| | - Latha Gullapudi
- Centre for Kidney Research and Innovation, University of Nottingham, Nottingham, UK
| | - Isma Kazmi
- Centre for Kidney Research and Innovation, University of Nottingham, Nottingham, UK
| | - Iosif A Mendichovszky
- Department of Radiology, Cambridge University Hospitals NHS Foundation Trust, Addenbrooke’s Hospital, Cambridge, UK
| | | | - Nicholas M Selby
- Centre for Kidney Research and Innovation, University of Nottingham, Nottingham, UK
| | - Harriet C Thoeny
- Department of Diagnostic, Pediatric, and Interventional Radiology, Inselspital University Hospital, Bern, Switzerland
| | - Nicolas Grenier
- Service d'Imagerie Diagnostique et Interventionnelle de l'Adulte, Centre Hospitalier Universitaire de Bordeaux, Bordeaux, France
| | - Jean-Paul Vallée
- Division of Radiology, Geneva University Hospitals, University of Geneva, Geneva, Switzerland
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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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Shehata M, Mahmoud A, Soliman A, Khalifa F, Ghazal M, Abou El-Ghar M, El-Melegy M, El-Baz A. 3D kidney segmentation from abdominal diffusion MRI using an appearance-guided deformable boundary. PLoS One 2018; 13:e0200082. [PMID: 30005069 PMCID: PMC6044527 DOI: 10.1371/journal.pone.0200082] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 06/19/2018] [Indexed: 12/20/2022] Open
Abstract
A new technique for more accurate automatic segmentation of the kidney from its surrounding abdominal structures in diffusion-weighted magnetic resonance imaging (DW-MRI) is presented. This approach combines a new 3D probabilistic shape model of the kidney with a first-order appearance model and fourth-order spatial model of the diffusion-weighted signal intensity to guide the evolution of a 3D geometric deformable model. The probabilistic shape model was built from labeled training datasets to produce a spatially variant, independent random field of region labels. A Markov-Gibbs random field spatial model with up to fourth-order interactions was adequate to capture the inhomogeneity of renal tissues in the DW-MRI signal. A new analytical approach estimated the Gibbs potentials directly from the DW-MRI data to be segmented, in order that the segmentation procedure would be fully automatic. Finally, to better distinguish the kidney object from the surrounding tissues, marginal gray level distributions inside and outside of the deformable boundary were modeled with adaptive linear combinations of discrete Gaussians (first-order appearance model). The approach was tested on a cohort of 64 DW-MRI datasets with b-values ranging from 50 to 1000 s/mm2. The performance of the presented approach was evaluated using leave-one-subject-out cross validation and compared against three other well-known segmentation methods applied to the same DW-MRI data using the following evaluation metrics: 1) the Dice similarity coefficient (DSC); 2) the 95-percentile modified Hausdorff distance (MHD); and 3) the percentage kidney volume difference (PKVD). High performance of the new approach was confirmed by the high DSC (0.95±0.01), low MHD (3.9±0.76) mm, and low PKVD (9.5±2.2)% relative to manual segmentation by an MR expert (a board certified radiologist).
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Affiliation(s)
- Mohamed Shehata
- Bioengineering Department, University of Louisville, Louisville, KY, United States of America
| | - Ali Mahmoud
- Bioengineering Department, University of Louisville, Louisville, KY, United States of America
| | - Ahmed Soliman
- Bioengineering Department, University of Louisville, Louisville, KY, United States of America
| | - Fahmi Khalifa
- Department of Electronics and Communications Engineering, Mansoura University, Mansoura, Egypt
| | - Mohammed Ghazal
- Bioengineering Department, University of Louisville, Louisville, KY, United States of America
- Electrical and Computer Engineering Department, Abu Dhabi University, Abu Dhabi, UAE
| | - Mohamed Abou El-Ghar
- Radiology Department, Urology and Nephrology Center, University of Mansoura, Mansoura, Egypt
| | - Moumen El-Melegy
- Department of Electrical Engineering, Assiut University, Assiut, Egypt
| | - Ayman El-Baz
- Bioengineering Department, University of Louisville, Louisville, KY, United States of America
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20
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Shehata M, Khalifa F, Soliman A, Ghazal M, Taher F, El-Ghar MA, Dwyer AC, Gimel'farb G, Keynton RS, El-Baz A. Computer-Aided Diagnostic System for Early Detection of Acute Renal Transplant Rejection Using Diffusion-Weighted MRI. IEEE Trans Biomed Eng 2018; 66:539-552. [PMID: 29993503 DOI: 10.1109/tbme.2018.2849987] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Early diagnosis of acute renal transplant rejection (ARTR) is critical for accurate treatment. Although the current gold standard, diagnostic technique is renal biopsy, it is not preferred due to its invasiveness, long recovery time (1-2 weeks), and potential for complications, e.g., bleeding and/or infection. METHODS This paper presents a computer-aided diagnostic (CAD) system for early ARTR detection using (3D + b-value) diffusion-weighted (DW) magnetic resonance imaging (MRI) data. The CAD process starts from kidney tissue segmentation with an evolving geometric (level-set-based) deformable model. The evolution is guided by a voxel-wise stochastic speed function, which follows from a joint kidney-background Markov-Gibbs random field model accounting for an adaptive kidney shape prior and on-going kidney-background visual appearances. A B-spline-based three-dimensional data alignment is employed to handle local deviations due to breathing and heart beating. Then, empirical cumulative distribution functions of apparent diffusion coefficients of the segmented DW-MRI at different b-values are collected as discriminatory transplant status features. Finally, a deep-learning-based classifier with stacked nonnegative constrained autoencoders is employed to distinguish between rejected and nonrejected renal transplants. RESULTS In our initial "leave-one-subject-out" experiment on 100 subjects, [Formula: see text] of the subjects were correctly classified. The subsequent four-fold and ten-fold cross-validations gave the average accuracy of [Formula: see text] and [Formula: see text], respectively. CONCLUSION These results demonstrate the promise of this new CAD system to reliably diagnose renal transplant rejection. SIGNIFICANCE The technology presented here can significantly impact the quality of care of renal transplant patients since it has the potential to replace the gold standard in kidney diagnosis, biopsy.
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21
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Renal scintigraphy for post-transplant monitoring after kidney transplantation. Transplant Rev (Orlando) 2018; 32:102-109. [DOI: 10.1016/j.trre.2017.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 10/30/2017] [Accepted: 12/18/2017] [Indexed: 01/22/2023]
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22
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Xie Y, Li Y, Wen J, Li X, Zhang Z, Li J, Zhao Y, Wang P, Zhang J, Tian Y, Zhang LJ, Lu GM. Functional Evaluation of Transplanted Kidneys with Reduced Field-of-View Diffusion-Weighted Imaging at 3T. Korean J Radiol 2018. [PMID: 29520177 PMCID: PMC5840048 DOI: 10.3348/kjr.2018.19.2.201] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Objective To determine the feasibility of reduced field-of-view diffusion-weighted imaging (rFOV DWI) with multi-b values to detect functional variability in transplanted kidneys. Materials and Methods Using a 3T MRI scanner, multi-b rFOV DWI of transplanted kidney or native kidney was performed in 40 renal transplantation recipients and 18 healthy volunteers. The patients were stratified, according to an estimated glomerular filtration rate (eGFR): Group 1, eGFR ≥ 60 mL/min/1.73 m2; Group 2, eGFR ≥ 30 mL/min/1.73 m2 and < 60 mL/min/1.73 m2; Group 3, eGFR < 30 mL/min/1.73 m2. Total apparent diffusion coefficient (ADCT), perfusion-free ADC (ADCD) and perfusion fraction (FP) of kidneys were calculated and compared among the four groups. Correlations between the imaging results and eGFR were assessed. Results All volunteers had eGFR ≥ 60 mL/min/1.73 m2, while 16, 16, and 8 patients were included in Groups 1, 2, and 3, respectively. In the renal cortex, ADCT was higher in Group 1 ([1.65 ± 0.13] × 10-3 mm2/s) than Group 3 ([1.44 ± 0.11] × 10-3 mm2/s) (p < 0.05), and the inter-group differences of FP values were significant (all p < 0.05) (0.330 ± 0.024, 0.309 ± 0.019, 0.278 ± 0.033, and 0.250 ± 0.028 for control group, Groups 1, 2, and 3, respectively). Renal cortical ADCT, ADCD, FP, and renal medullary ADCT and FP correlated positively with eGFR (r = 0.596, 0.403, 0.711, 0.341, and 0.323, respectively; all p < 0.05). When using 0.278 as the cutoff value, renal cortical FP had a sensitivity of 97.1% and a specificity of 66.7% for predicting decreased renal function. Conclusion Multi-b rFOV DWI presents transplanted kidneys with high resolution, which is a promising functional tool for non-invasively monitoring function of transplanted kidneys.
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Affiliation(s)
- Yuan Xie
- Department of Medical Imaging, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Yanjun Li
- Department of Medical Imaging, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Jiqiu Wen
- Department of National Clinical Research Center of Kidney Diseases, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Xue Li
- Department of National Clinical Research Center of Kidney Diseases, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Zhe Zhang
- Department of National Clinical Research Center of Kidney Diseases, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Jianrui Li
- Department of Medical Imaging, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Yan'e Zhao
- Department of Medical Imaging, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Peng Wang
- Department of Medical Imaging, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Jun Zhang
- Department of Medical Imaging, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Ying Tian
- Department of Medical Imaging, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Long Jiang Zhang
- Department of Medical Imaging, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
| | - Guang Ming Lu
- Department of Medical Imaging, Jinling Hospital, School of Medicine, Nanjing University, Nanjing 210002, China
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Hollis E, Shehata M, Abou El-Ghar M, Ghazal M, El-Diasty T, Merchant M, Switala AE, El-Baz A. Statistical analysis of ADCs and clinical biomarkers in detecting acute renal transplant rejection. Br J Radiol 2017; 90:20170125. [PMID: 28937266 DOI: 10.1259/bjr.20170125] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE The main goal of this study is to determine which parameters [e.g. clinical biomarkers, demographics and image-markers using 4D (3D + b-value) diffusion-weighted MRI (DW-MRI)] are more correlated with transplanted kidney status in patients who have undergone kidney transplantation, and can be used for early assessment of acute renal rejection. METHODS The study included 16 patients with stable graft function and 37 patients with acute rejection (AR), determined by renal biopsy post-transplantation. 3D DW-MRI of each allograft had been acquired using a series of b-values 50 and 100-1000 in steps of 100 smm-2. The kidney was automatically segmented and co-aligned across series for motion correction using geometric deformable models. Volume-averaged apparent diffusion coefficients (ADCs) at each b-value were calculated. All possible subsets of ADC were used, along with patient age, sex, serum plasma creatinine (SPCr) and creatinine clearance (CrCl), as predictors in 211 logistic regression models where AR was the outcome variable. Predictive value of ADC at each b-value was assessed using its Akaike weight. RESULTS ANOVA of the saturated model found that odds of AR depended significantly on SPCr, CrCl and ADC at b = 500, 600, 700 and 900 smm-2. The model incorporating ADC at b = 100 and700 smm-2 had the lowest value of the Akaike information criterion; the same two b-values also had the greatest Akaike weights. For comparison, the top 10 submodels and the full model were reported. CONCLUSION Preliminary findings suggest that ADC provides improved detection of AR than lab values alone. At least two non-zero gradient strengths should be used for optimal results. Advances in knowledge: This paper investigated possible correlations between image-based and clinical biomarkers, and the fusion of both with respect to biopsy diagnosis of AR.
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Affiliation(s)
- Elizabeth Hollis
- 1 Department of Bioengineering,BioImaging Laboratory, University of Louisville , Louisville, KY , USA.,2 Department of Pharmacology and Toxicology, University of Louisville , Louisville, KY , USA
| | - Mohamed Shehata
- 1 Department of Bioengineering,BioImaging Laboratory, University of Louisville , Louisville, KY , USA
| | - Mohamed Abou El-Ghar
- 3 Department of Radiology,Urology and Nephrology Center, University of Mansoura , Mansoura , Egypt
| | - Mohammed Ghazal
- 1 Department of Bioengineering,BioImaging Laboratory, University of Louisville , Louisville, KY , USA.,4 Department of Electrical and Computer Engineering, Abu Dhabi University , Abu Dhabi , UAE
| | - Tarek El-Diasty
- 3 Department of Radiology,Urology and Nephrology Center, University of Mansoura , Mansoura , Egypt
| | - Michael Merchant
- 2 Department of Pharmacology and Toxicology, University of Louisville , Louisville, KY , USA
| | - Andrew E Switala
- 1 Department of Bioengineering,BioImaging Laboratory, University of Louisville , Louisville, KY , USA
| | - Ayman El-Baz
- 1 Department of Bioengineering,BioImaging Laboratory, University of Louisville , Louisville, KY , USA
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24
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Misra P, Kirpalani A, Leung G, Vlachou PA, Lee JY, Jothy S, Zaltzman J, Yuen DA. The role of thrombectomy and diffusion-weighted imaging with MRI in post-transplant renal vein thrombosis: a case report. BMC Nephrol 2017; 18:224. [PMID: 28693502 PMCID: PMC5504730 DOI: 10.1186/s12882-017-0618-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 06/09/2017] [Indexed: 01/06/2023] Open
Abstract
Background Surgical thrombectomy in the context of acute renal vein thrombosis (RVT) post-transplantation has had limited success, with considerable variation in the surgical techniques used. Unfortunately, it is usually followed by allograft nephrectomy within a few days if rapid allograft recovery does not ensue. We report a case of acute RVT in which nephrectomy was not performed despite a prolonged requirement for dialysis post-thrombectomy, but with recovery of renal function 2 weeks later. We also report the findings of serial MRI with diffusion-weighted imaging (DW-MRI) throughout the patient’s recovery, which provided novel insights into allograft microvascular perfusion changes post-thrombectomy. Case presentation A 65-year old patient underwent living-unrelated kidney transplantation complicated by acute RVT. Surgical thrombectomy and irrigation led to a delayed, but significant, recovery of renal function. Serial non-contrast DW-MRI scanning was used to non-invasively assess microvascular renal blood flow post-operatively. Unlike standard Doppler ultrasonography, DW-MRI documented reduced microvascular perfusion initially, with gradual but incomplete recovery that mirrored the partial improvement in renal function. Conclusions Our findings suggest that surgical thrombectomy may be more effective than previously described if followed by careful patient observation. Moreover, diffusion-weighted MRI appears to provide important insights into the pathophysiology of delayed graft function and deserves further investigation.
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Affiliation(s)
- Paraish Misra
- Division of Nephrology, St. Michael's Hospital, University of Toronto, Toronto, ON, M5B 1W8, Canada
| | - Anish Kirpalani
- Department of Medical Imaging, St. Michael's Hospital, University of Toronto, 30 Bond Street, 3 Cardinal Carter South, Toronto, ON, M5B 1W8, Canada.,Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Rm 509, 5th Floor, 209 Victoria Street, Toronto, ON, M5B 1T8, Canada
| | - General Leung
- Department of Medical Imaging, St. Michael's Hospital, University of Toronto, 30 Bond Street, 3 Cardinal Carter South, Toronto, ON, M5B 1W8, Canada.,Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Rm 509, 5th Floor, 209 Victoria Street, Toronto, ON, M5B 1T8, Canada
| | - Paraskevi A Vlachou
- Department of Medical Imaging, St. Michael's Hospital, University of Toronto, 30 Bond Street, 3 Cardinal Carter South, Toronto, ON, M5B 1W8, Canada
| | - Jason Y Lee
- Division of Urology, Department of Surgery, St. Michael's Hospital, University of Toronto, 61 Queen Street East Suite 2-012, Toronto, ON, M5C 2T2, Canada
| | - Serge Jothy
- Department of Laboratory Medicine, St. Michael's Hospital, 30 Bond Street, Room 2-015 CC Wing, Toronto, ON, M5B 1W8, Canada.,Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Rm 509, 5th Floor, 209 Victoria Street, Toronto, ON, M5B 1T8, Canada
| | - Jeffrey Zaltzman
- Division of Nephrology, St. Michael's Hospital, University of Toronto, Toronto, ON, M5B 1W8, Canada.,Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Rm 509, 5th Floor, 209 Victoria Street, Toronto, ON, M5B 1T8, Canada
| | - Darren A Yuen
- Division of Nephrology, St. Michael's Hospital, University of Toronto, Toronto, ON, M5B 1W8, Canada. .,Keenan Research Centre for Biomedical Science, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Rm 509, 5th Floor, 209 Victoria Street, Toronto, ON, M5B 1T8, Canada.
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25
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Selection for biopsy of kidney transplant patients by diffusion-weighted MRI. Eur Radiol 2017; 27:4336-4344. [PMID: 28374076 DOI: 10.1007/s00330-017-4814-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 02/26/2017] [Accepted: 03/14/2017] [Indexed: 10/19/2022]
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26
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Towards non-invasive diagnostic techniques for early detection of acute renal transplant rejection: A review. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2017. [DOI: 10.1016/j.ejrnm.2016.11.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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27
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Hanssen O, Erpicum P, Lovinfosse P, Meunier P, Weekers L, Tshibanda L, Krzesinski JM, Hustinx R, Jouret F. Non-invasive approaches in the diagnosis of acute rejection in kidney transplant recipients. Part I. In vivo imaging methods. Clin Kidney J 2016. [PMID: 28643821 PMCID: PMC5469561 DOI: 10.1093/ckj/sfw062] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Kidney transplantation (KTx) represents the best available treatment for patients with end-stage renal disease. Still, full benefits of KTx are undermined by acute rejection (AR). The diagnosis of AR ultimately relies on transplant needle biopsy. However, such an invasive procedure is associated with a significant risk of complications and is limited by sampling error and interobserver variability. In the present review, we summarize the current literature about non-invasive approaches for the diagnosis of AR in kidney transplant recipients (KTRs), including in vivo imaging, gene expression profiling and omics analyses of blood and urine samples. Most imaging techniques, like contrast-enhanced ultrasound and magnetic resonance, exploit the fact that blood flow is significantly lowered in case of AR-induced inflammation. In addition, AR-associated recruitment of activated leukocytes may be detectable by 18F-fluoro-deoxy-glucose positron emission tomography. In parallel, urine biomarkers, including CXCL9/CXCL10 or a three-gene signature of CD3ε, IP-10 and 18S RNA levels, have been identified. None of these approaches has been adopted yet in the clinical follow-up of KTRs, but standardization of procedures may help assess reproducibility and compare diagnostic yields in large prospective multicentric trials.
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Affiliation(s)
- Oriane Hanssen
- Division of Nephrology, University of Liège Academic Hospital (ULg CHU), Avenue Hippocrate, 13, B-4000 Liège, Belgium
| | - Pauline Erpicum
- Division of Nephrology, University of Liège Academic Hospital (ULg CHU), Avenue Hippocrate, 13, B-4000 Liège, Belgium.,GIGA Cardiovascular Sciences, University of Liège, Liège, Belgium
| | - Pierre Lovinfosse
- Division of Nuclear Medicine, University of Liège Academic Hospital (ULg CHU), Liège, Belgium
| | - Paul Meunier
- Division of Radiology, University of Liège Academic Hospital (ULg CHU), Liège, Belgium
| | - Laurent Weekers
- Division of Nephrology, University of Liège Academic Hospital (ULg CHU), Avenue Hippocrate, 13, B-4000 Liège, Belgium
| | - Luaba Tshibanda
- Division of Radiology, University of Liège Academic Hospital (ULg CHU), Liège, Belgium
| | - Jean-Marie Krzesinski
- Division of Nephrology, University of Liège Academic Hospital (ULg CHU), Avenue Hippocrate, 13, B-4000 Liège, Belgium.,GIGA Cardiovascular Sciences, University of Liège, Liège, Belgium
| | - Roland Hustinx
- Division of Nuclear Medicine, University of Liège Academic Hospital (ULg CHU), Liège, Belgium
| | - François Jouret
- Division of Nephrology, University of Liège Academic Hospital (ULg CHU), Avenue Hippocrate, 13, B-4000 Liège, Belgium.,GIGA Cardiovascular Sciences, University of Liège, Liège, Belgium
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28
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Thölking G, Schuette-Nuetgen K, Kentrup D, Pawelski H, Reuter S. Imaging-based diagnosis of acute renal allograft rejection. World J Transplant 2016; 6:174-182. [PMID: 27011915 PMCID: PMC4801793 DOI: 10.5500/wjt.v6.i1.174] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Revised: 08/28/2015] [Accepted: 12/02/2015] [Indexed: 02/05/2023] Open
Abstract
Kidney transplantation is the best available treatment for patients with end stage renal disease. Despite the introduction of effective immunosuppressant drugs, episodes of acute allograft rejection still endanger graft survival. Since efficient treatment of acute rejection is available, rapid diagnosis of this reversible graft injury is essential. For diagnosis of rejection, invasive core needle biopsy of the graft is the “gold-standard”. However, biopsy carries the risk of significant graft injury and is not immediately feasible in patients taking anticoagulants. Therefore, a non-invasive tool assessing the whole organ for specific and fast detection of acute allograft rejection is desirable. We herein review current imaging-based state of the art approaches for non-invasive diagnostics of acute renal transplant rejection. We especially focus on new positron emission tomography-based as well as targeted ultrasound-based methods.
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29
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Ye J, Kumar BS, Li XB, Li HM, Zhou YW, Liu LQ. Clinical applications of diffusion-weighted magnetic resonance imaging in diagnosis of renal lesions - a systematic review. Clin Physiol Funct Imaging 2015; 37:459-473. [PMID: 26648310 DOI: 10.1111/cpf.12313] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 09/21/2015] [Indexed: 01/07/2023]
Abstract
Diffusion-weighted magnetic resonance imaging (DW-MRI) is an established technique to detect the changes of the diffusion of water in biological tissues and reflect the pathophysiological process on the molecular level. It is a promising non-invasive imaging modality in detection of microstructural and functional changes in pathologies of kidney. To systematically review the research advancement of the DW-MRI in diagnosis of renal lesions, a systematic literature search was performed up to 8 October 2014 using the MEDLINE/PubMed and Embase databases for articles reporting on DW-MRI in diagnosis of renal lesions. Only articles with full data about DW-MRI application with potential implication in solving usually encountered clinical challenges about renal lesions were finally examined. The clinical application of DW-MRI allows a better understanding of some pathologic conditions of the kidney including renal insufficiency, renal artery stenosis, ureteral obstruction, foetal kidney disease, hydronephrosis and pyonephrosis. In addition, DW-MRI can also provide clinicians with the information of function evaluation of renal allograft and curative effect assessment of renal tumour. In summary, performance of renal DW-MRI, presuming that measurements are high quality, will further boost this modality, particularly for early detection of diffusion renal conditions, as well as more accurate characterization of renal lesions.
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Affiliation(s)
- Jing Ye
- Department of Imaging, Northern Jiangsu People's Hospital, Yangzhou, China
| | | | - Xiao-Bo Li
- Department of Neurology, Northern Jiangsu People's Hospital, Yangzhou, China
| | - Hong-Mei Li
- Department of Imaging, Northern Jiangsu People's Hospital, Yangzhou, China
| | - Ying-Wen Zhou
- Department of Imaging, Northern Jiangsu People's Hospital, Yangzhou, China
| | - Li-Qin Liu
- Department of Oncology, Northern Jiangsu People's Hospital, Yangzhou, China
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30
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Yalçin-Şafak K, Ayyildiz M, Ünel SY, Umarusman-Tanju N, Akça A, Baysal T. The relationship of ADC values of renal parenchyma with CKD stage and serum creatinine levels. Eur J Radiol Open 2015; 3:8-11. [PMID: 27069972 PMCID: PMC4811857 DOI: 10.1016/j.ejro.2015.10.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 10/22/2015] [Accepted: 10/26/2015] [Indexed: 01/22/2023] Open
Abstract
Purpose To evaluate the relationship of apparent diffusion coefficient (ADC) values of renal parenchyma with chronic kidney disease (CKD) stage and serum creatinine levels. Materials and methods One hundred and ten patients who had undergone magnetic resonance imaging of the upper abdomen for different reasons were retrospectively studied. A region of interest (ROI) was placed on the renal parenchyma for measurement of ADC values of both kidneys, without any preference for cortex or medulla. Three circular ROIs were placed-one each in the upper pole, interpolar region and lower pole of both kidneys. The mean ADC values were recorded for each patient and the relationship between ADC values and stage of CKD and serum creatinine levels were evaluated. Results Statistically significant difference was determined between the ADC values of the cases according to CKD stages (p < 0.001). Paired comparisons performed to determine the group that caused the difference revealed that median ADC values of healthy subjects who formed the control group was statistically significantly higher than that of the cases with stage 3, stage 4 and stage 5 CKD (p: 0.008; p: 0.008; and p: 0.002, respectively). Sensitivity and specificity were found to be 75.44% and 69.81%, respectively in detecting stage 3, stage 4 and stage 5 CKD among the cases with ADC values of 1151 and lower. Conclusion ADC values can play a role in the evaluation of renal dysfunction. However, population-and protocol-based cut-off ADC values are needed to identify renal dysfunction and to distinguish between different stages of CKD.
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Affiliation(s)
- Kadihan Yalçin-Şafak
- Kartal Dr Lütfü Kırdar Training and Research Hospital-Radiology Department, Turkey
| | - Muhammet Ayyildiz
- Kartal Dr Lütfü Kırdar Training and Research Hospital-Radiology Department, Turkey
| | - Sacide Yekta Ünel
- Kartal Dr Lütfü Kırdar Training and Research Hospital-Radiology Department, Turkey
| | | | - Ahmet Akça
- Kartal Dr Lütfü Kırdar Training and Research Hospital-Radiology Department, Turkey
| | - Tamer Baysal
- Kartal Dr Lütfü Kırdar Training and Research Hospital-Radiology Department, Turkey
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31
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Renal function impairment in liver cirrhosis: preliminary results with diffusion-weighted imaging at 3 T. AJR Am J Roentgenol 2015; 204:1024-30. [PMID: 25905937 DOI: 10.2214/ajr.14.13418] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
OBJECTIVE The purpose of this study was to investigate the utility of diffusion-weighted MRI (DWI) at 3 T for assessing renal function impairment in patients with liver cirrhosis. MATERIALS AND METHODS Sixty-four patients with liver cirrhosis who underwent both DWI at 3 T and renal function testing were retrospectively included. Twenty-two patients had moderate or severe renal function impairment (group A, estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73 m(2)) and 42 had good renal function or mild renal function impairment (group B, eGFR ≥ 60 mL/min/1.73 m(2)). Cortical and medullary apparent diffusion coefficients (ADCs) of both kidneys were measured. AUC was assessed for predicting group A with ADC. The correlation between renal ADC and eGFR or serum creatinine was analyzed. The reproducibility of ADC measurement was investigated. RESULTS Both cortical and medullary ADCs were lower in group A than in group B, (both, p < 0.05). In all patients, AUCs were 0.784 and 0.737 with cortical and medullary ADCs, respectively, for predicting group A. Both cortical and medullary ADCs had linear correlation with eGFR or serum creatinine (both, p < 0.05). The reproducibility of measurement was excellent for cortex (intraclass coefficient [ICC] = 0.808) and good for medulla (ICC = 0.692), with 1.6% or less variability. CONCLUSION DWI may have potential for assessing renal function impairment in patients with liver cirrhosis.
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Palmucci S, Cappello G, Attinà G, Foti PV, Siverino ROA, Roccasalva F, Piccoli M, Sinagra N, Milone P, Veroux M, Ettorre GC. Diffusion weighted imaging and diffusion tensor imaging in the evaluation of transplanted kidneys. Eur J Radiol Open 2015; 2:71-80. [PMID: 26937439 PMCID: PMC4750625 DOI: 10.1016/j.ejro.2015.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 05/04/2015] [Indexed: 01/29/2023] Open
Abstract
OBJECTIVE The aim of this study is to investigate the relation between renal indexes and functional MRI in a population of kidney transplant recipients who underwent MR with diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) of the transplanted graft. METHOD Study population included 40 patients with single kidney transplant. The patients were divided into 3 groups, on the basis of creatinine clearance (CrCl) values calculated using Cockcroft-Gault formula: group A, including patients with normal renal function (CrCl ≥ 60 mL/min); group B, which refers to patients with moderate renal impairment (CrCl > 30 but <60 mL/min); and, finally, group C, which means severe renal deterioration (CrCl ≤ 30 mL/min). All patients were investigated with a 1.5 Tesla MRI scanner, acquiring DWI and DTI sequences. A Mann-Whitney U test was adopted to compare apparent diffusion coefficients (ADCs) and fractional anisotropy (FA) measurements between groups. Receiver operating characteristic (ROC) curves were created for prediction of normal renal function (group A) and renal failure (group C). Pearson correlation was performed between renal clearance and functional imaging parameter (ADC and FA), obtained for cortical and medullar regions. RESULTS Mann-Whitney U test revealed a highly significant difference (p < 0.01) between patients with low CrCl (group C) and normal CrCl (group A) considering both medullar ADC and FA and cortical ADC. Regarding contiguous groups, the difference between group B and C was highly significant (p < 0.01) for medullar ADC and significant (p < 0.05) for cortical ADC and medullar FA. No difference between these groups was found considering cortical FA. Analyzing groups A and B, we found a significant difference (p < 0.05) for medullar both ADC and FA, while no difference was found for cortical ADC and FA. Strongest Pearson correlation was found between CrCl and medullar ADC (r = 0.65). For predicting normal renal function or severe renal impairment, highest values of AUC were observed using medullar ADC cut-off values (respectively 0.885 and 0.871); medullar FA showed also high accuracy (respectively 0.831 and 0.853). CONCLUSIONS DWI and DTI are promising tools for non-invasive monitoring of renal function; medullar ADC proved to be the best parameter for renal function assessment.
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Affiliation(s)
- Stefano Palmucci
- Radiodiagnostic and Radiotherapy Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
| | - Giuseppina Cappello
- Radiodiagnostic and Radiotherapy Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
| | - Giancarlo Attinà
- Radiodiagnostic and Radiotherapy Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
| | - Pietro Valerio Foti
- Radiodiagnostic and Radiotherapy Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
| | - Rita Olivia Anna Siverino
- Radiodiagnostic and Radiotherapy Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
| | - Federica Roccasalva
- Radiodiagnostic and Radiotherapy Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
| | - Marina Piccoli
- Radiodiagnostic and Radiotherapy Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
| | - Nunziata Sinagra
- Vascular Surgery and Organ Transplant Unit, Department of Surgery, Transplantation and Advanced Technologies, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
| | - Pietro Milone
- Radiodiagnostic and Radiotherapy Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
| | - Massimiliano Veroux
- Vascular Surgery and Organ Transplant Unit, Department of Surgery, Transplantation and Advanced Technologies, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
| | - Giovanni Carlo Ettorre
- Radiodiagnostic and Radiotherapy Unit, University Hospital "Policlinico-Vittorio Emanuele", Via Santa Sofia 78, 95123 Catania, Italy
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33
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Detection of renal allograft rejection using blood oxygen level-dependent and diffusion weighted magnetic resonance imaging: a retrospective study. BMC Nephrol 2014; 15:158. [PMID: 25270976 PMCID: PMC4192395 DOI: 10.1186/1471-2369-15-158] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Accepted: 09/25/2014] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Acute rejection (AR) and acute tubular necrosis (ATN) are main causes of early renal allograft dysfunction. Blood oxygen level-dependent magnetic resonance imaging (BOLD MRI) and Diffusion weighted (DW) MRI can provide valuable information about changes of oxygen bioavailability and water diffusion by measuring R2* or apparent diffusion coefficient (ADC) respectively. We aimed to determine the value of BOLD MRI and DW MRI in detecting causes for early allograft dysfunction in renal allograft recipients. METHODS Fifty patients received renal allografts from deceased donors were analyzed, including 35 patients with normal renal function (control group), 10 AR patients and 5 ATN patients. Cortical R2* (CR2*) and medullary R2* (MR2*) were measured by BOLD MRI. Ten diffusion gradient b values (0, 5, 10, 20, 50, 100, 200, 400, 800, 1200s/mm2) were used in DW MRI. ADC values were measured in renal cortex (CADC) and medulla (MADC). CADCl and MADCl were measured under low b values (b ≤ 200 s/mm2), while CADCh and MADCh were measured under high b values (b > 200 s/mm2). RESULTS MR2* was significantly lower in AR group (18.2 ± 1.5/s) than control group (23.8 ± 5.0/s, p = 0.001) and ATN group (25.8 ± 5.0/s, p = 0.004). There was a tendency of lower levels on CADCl, MADCl, CADCh or MADCh in AR group than in control group. There were no differences on ADC values between AR group and ATN group. CONCLUSIONS BOLD MRI was a valuable method in detection of renal allografts with acute rejection.
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Lal H, Helavar RV, Gamanagatti S, Jain S, Kumar R. Imaging in renal transplant: Review. INDIAN JOURNAL OF TRANSPLANTATION 2014. [DOI: 10.1016/j.ijt.2014.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Eisenberger U, Binser T, Thoeny HC, Boesch C, Frey FJ, Vermathen P. Living renal allograft transplantation: diffusion-weighted MR imaging in longitudinal follow-up of the donated and the remaining kidney. Radiology 2013; 270:800-8. [PMID: 24475796 DOI: 10.1148/radiol.13122588] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To determine whether diffusion-weighted (DW) magnetic resonance (MR) imaging in living renal allograft donation allows monitoring of potential changes in the nontransplanted remaining kidney of the donor because of unilateral nephrectomy and changes in the transplanted kidney before and after transplantation in donor and recipient, respectively, and whether DW MR parameters are correlated in the same kidney before and after transplantation. MATERIALS AND METHODS The study protocol was approved by the local ethics committee; written informed consent was obtained. Thirteen healthy kidney donors and their corresponding recipients prospectively underwent DW MR imaging (multiple b values) in donors before donation and in donors and recipients at day 8 and months 3 and 12 after donation. Total apparent diffusion coefficient (ADCT) values were determined; contribution of microcirculation was quantified in perfusion fraction (FP). Longitudinal changes of diffusion parameters were compared (repeated-measures one-way analysis of variance with post hoc pairwise comparisons). Correlations were tested (linear regression). RESULTS ADCT values in nontransplanted kidney of donors increased from a preexplantation value of (188 ± 9 [standard deviation]) to (202 ± 11) × 10(-5) mm(2)/sec in medulla and from (199 ± 11) to (210 ± 13) × 10(-5) mm(2)/sec in cortex 1 week after donation (P < .004). Medullary, but not cortical, ADCT values stayed increased up to 1 year. ADCT values in allografts in recipients were stable. Compared with values obtained before transplantation in donors, the corticomedullary difference was reduced in allografts (P < .03). Cortical ADCT values correlated with estimated glomerular filtration rate in recipients (R = 0.56, P < .001) but not donors. Cortical ADCT values in the same kidney before transplantation in donors correlated with those in recipients on day 8 after transplantation (R = 0.77, P = .006). FP did not show significant changes. CONCLUSION DW MR imaging depicts early adaptations in the remaining nontransplanted kidney of donors after nephrectomy. All diffusion parameters remained constant in allograft recipients after transplantation. This method has potential monitoring utility, although assessment of clinical relevance is needed.
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Affiliation(s)
- Ute Eisenberger
- From the Department of Nephrology and Hypertension (U.E., F.J.F.), Department of Clinical Research (T.B., C.B., P.V.), and Department of Radiology, Neuroradiology and Nuclear Medicine (H.C.T.), University Hospital of Bern, Bern, Switzerland
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