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Jiang B, Yu Y, Wan J, Xu R, Ma J, Tian Y, Hu L, Wu P, Hu C, Zhu M. The Use of Diffusion Tensor Imaging in the Identification of Acute Rejection and Chronic Allograft Nephropathy After Renal Transplantation. J Magn Reson Imaging 2024; 59:2082-2088. [PMID: 37807929 DOI: 10.1002/jmri.29042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 09/20/2023] [Accepted: 09/20/2023] [Indexed: 10/10/2023] Open
Abstract
BACKGROUND Identifying the cause of renal allograft dysfunction is important for the clinical management of kidney transplant recipients. PURPOSE To evaluate the diagnostic efficiency of diffusion tensor imaging (DTI) for identifying allografts with acute rejection (AR) and chronic allograft nephropathy (CAN). STUDY TYPE Prospective. SUBJECTS Seventy-seven renal transplant patients (aged 42.5 ± 9.5 years), including 29 patients with well-functioning stable allografts (Control group), 25 patients diagnosed with acute rejection (AR group), and 23 patients diagnosed with chronic allograft nephropathy (CAN group). FIELD STRENGTH/SEQUENCE 1.5 T/T2-weighted imaging and DTI. ASSESSMENT The serum creatinine, proteinuria, pathologic results, and fractional anisotropy (FA) values were obtained and compared among the three groups. STATISTICAL TEST One-way analysis of variance; correlation analysis; independent-sample t-test; intraclass correlation coefficients and receiver operating characteristic curves. Statistical significance was set to a P-value <0.05. RESULTS The AR and CAN groups presented with significantly elevated serum creatinine as compared with the Control group (191.8 ± 181.0 and 163.1 ± 115.8 μmol/L vs. 82.3 ± 20.9 μmol/L). FA decreased in AR group (cortical/medullary: 0.13 ± 0.02/0.31 ± 0.07) and CAN group (cortical/medullary: 0.11 ± 0.02/0.27 ± 0.06), compared with the Control group (cortical/medullary: 0.15 ± 0.02/0.35 ± 0.05). Cortical FA in the AR group was higher than in the CAN group. The area under the curve (AUC) for identifying AR from normal allografts was 0.756 and 0.744 by cortical FA and medullary FA, respectively. The AUC of cortical FA and medullary FA for differentiating CAN from normal allografts was 0.907 and 0.830, respectively. The AUC of cortical FA and medullary FA for distinguishing AR and CAN from normal allografts was 0.828 and 0.785, respectively. Cortical FA was able to distinguish between AR and CAN with an AUC of 0.728. DATA CONCLUSION DTI was able to detect patients with dysfunctional allografts. Cortical FA can further distinguish between AR and CAN. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Bin Jiang
- Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Yixing Yu
- Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jiayi Wan
- Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Rui Xu
- Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Jiali Ma
- Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Yangyang Tian
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Linkun Hu
- Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Peng Wu
- Philips Healthcare, Shanghai, China
| | - Chunhong Hu
- Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Mo Zhu
- Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, China
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Farg HM, El-Diasty T, Ali-El-Dein B, Refaie A, Abou El-Ghar M. Functional MRI evaluation of blood oxygen dependent (BOLD) in renal allograft dysfunction: a prospective study. Acta Radiol 2024; 65:397-405. [PMID: 38146146 DOI: 10.1177/02841851231217052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2023]
Abstract
BACKGROUND Blood oxygen level dependent-magnetic resonance imaging (BOLD-MRI) is a non-invasive functional imaging technique that can be used to assess renal allograft dysfunction. PURPOSE To evaluate the diagnostic performance of BOLD-MRI using a 3-T scanner in discriminating causes of renal allograft dysfunction in the post-transplant period. MATERIAL AND METHODS This prospective study was conducted on 112 live donor-renal allograft recipients: 53 with normal graft function, as controls; 18 with biopsy-proven acute rejection (AR); and 41 with biopsy-proven acute tubular necrosis (ATN). Multiple fast-field echo sequences were performed to obtain T2*-weighted images. Cortical R2* (CR2*) level, medullary R2* (MR2*) level, and medullary over cortical R2* ratio (MCR) were measured in all participants. RESULTS The mean MR2* level was significantly lower in the AR group (20.8 ± 2.8/s) compared to the normal group (24 ± 2.4/s, P <0.001) and ATN group (27.4 ± 1.7/s, P <0.001). The MCR was higher in ATN group (1.47 ± 0.18) compared to the AR group (1.18 ± 0.17) and normal functioning group (1.34 ± 0.2). Both MR2* (area under the curve [AUC] = 0.837, P <0.001) and MCR (AUC = 0.727, P = 0.003) can accurately discriminate ATN from AR, however CR2* (AUC = 0.590, P = 0.237) showed no significant difference between both groups. CONCLUSION In early post-transplant renal dysfunction, BOLD-MRI is a valuable non-invasive diagnostic technique that can differentiate between AR and ATN by measuring changes in intra-renal tissue oxygenation.
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Affiliation(s)
- Hashim Mohamed Farg
- Radiology Department, Urology and Nephrology Center, Mansoura University, Egypt
| | - Tarek El-Diasty
- Radiology Department, Urology and Nephrology Center, Mansoura University, Egypt
| | - Bedeir Ali-El-Dein
- Urology Department, Urology and Nephrology Center, Mansoura University, Egypt
| | - Ayman Refaie
- Nephrology Department, Urology and Nephrology Center, Mansoura University, Egypt
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Faccinetto ACB, Santos GRF, Taguchi JC, Orellana HC, Galhardo A, Kanhouche G, Barteczko MLM, Tedesco Júnior H, Bravo-Valenzuela NJM, Moises VA, Pestana JOM, Silva CMC, Barbosa AHP. Retrospective analysis of percutaneous intervention of the renal artery in transplanted kidneys in children and adolescents at a tertiary public hospital. PLoS One 2024; 19:e0297975. [PMID: 38551934 PMCID: PMC10980230 DOI: 10.1371/journal.pone.0297975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 01/15/2024] [Indexed: 04/01/2024] Open
Abstract
BACKGROUND This study evaluated the long-term effects of percutaneous intervention in children and adolescents with transplant renal artery stenosis (TRAS). METHODS Twenty patients had significant stenosis (>50%) and underwent percutaneous transluminal angioplasty (PTA/stenting) (TRAS group-intervention); 14 TNS (non-significant group -control) patients did not have significant stenosis (≤50%) and were treated clinically. The combined primary endpoints were death from all causes and late graft failure. The secondary endpoints were serum creatinine (SCr), systolic blood pressure (SBP), and diastolic blood pressure (DBP). RESULTS No statistically significant difference was found between TRAS-Intervention(N = 20) and TNS groups-Control (N = 14) for these clinical parameters: deaths, 1 (5.0%) vs. 0 (0.0%) (p = 1.000) and graft loss, 4 (20.0%) vs. 2 (14.3%) (p = 1.000). For the secondary endpoints, after 1 month and 1 year the values of SCr, SBP, and DBP were similar between the two groups but not statistically significant. DISCUSSION In the TRAS group (intervention), the stent implantation was beneficial for treating refractory hypertension and reducing blood pressure (BP) in children and adolescents. Despite the outcomes being similar in the two groups, it can be inferred that the patients in the TRAS group (intervention) would have had a worse outcome without the percutaneous intervention. CONCLUSION TRAS treatment with stenting can be considered for children and adolescents. Because the sample in the present study comprised of only a specific population, further studies are needed for generalization. TRIAL REGISTRATION The trial was registered at clinictrials.gov with trial registration number NCT04225338.
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Affiliation(s)
| | | | - Juliana Cristina Taguchi
- Department of Medicine, Cardiology Division, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Henry Campos Orellana
- Department of Medicine, Cardiology Division, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Attílio Galhardo
- Department of Medicine, Cardiology Division, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Gabriel Kanhouche
- Department of Medicine, Cardiology Division, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | | | - Hélio Tedesco Júnior
- Division of Nephrology, Hospital do Rim e Hipertensão, A Part of the Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Nathalie Jeanne Magioli Bravo-Valenzuela
- Department of Medicine, Cardiology Division, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
- Faculty of Medicine/ Federal University of Rio de Janeiro (UFRJ), Department of Pediatrics, Pediatric Cardiology Discipline, IPPMG, Rio de Janeiro, RJ, Brazil
| | - Valdir Ambrósio Moises
- Department of Medicine, Cardiology Division, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - José Osmar Medina Pestana
- Division of Nephrology, Hospital do Rim e Hipertensão, A Part of the Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - Célia Maria Camelo Silva
- Department of Medicine, Cardiology Division, Universidade Federal de São Paulo (UNIFESP), São Paulo, SP, Brazil
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Al-Shaqsi Y, Peycelon M, Paye-Jaouen A, Carricaburu E, Tanase A, Grapin-Dagorno C, El-Ghoneimi A. Evaluating pediatric ureteropelvic junction obstruction: Dynamic magnetic resonance urography vs renal scintigraphy 99m-technetium mercaptoacetyltriglycine. World J Radiol 2024; 16:49-57. [PMID: 38596171 PMCID: PMC10999956 DOI: 10.4329/wjr.v16.i3.49] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/18/2024] [Accepted: 03/12/2024] [Indexed: 03/26/2024] Open
Abstract
BACKGROUND Ureteropelvic junction obstruction (UPJO) is a common congenital urinary tract disorder in children. It can be diagnosed as early as in utero due to the presence of hydronephrosis or later in life due to symptomatic occurrence. AIM To evaluate the discrepancy between dynamic contrast-enhanced magnetic resonance urography (dMRU) and scintigraphy 99m-technetium mercaptoacetyltriglycine (MAG-3) for the functional evaluation of UPJO. METHODS Between 2016 and 2020, 126 patients with UPJO underwent surgery at Robert Debré Hospital. Of these, 83 received a prenatal diagnosis, and 43 were diagnosed during childhood. Four of the 126 patients underwent surgery based on the clinical situation and postnatal ultrasound findings without undergoing functional imaging evaluation. Split renal function was evaluated preoperatively using scintigraphy MAG-3 (n = 28), dMRU (n = 53), or both (n = 40). In this study, we included patients who underwent surgery for UPJO and scintigraphy MAG-3 + dMRU but excluded those who underwent only scintigraphy MAG-3 or dMRU. The patients were divided into groups A (< 10% discrepancy) and B (> 10% discrepancy). We examined the discrepancy in split renal function between the two modalities and investigated the possible risk factors. RESULTS The split renal function between the two kidneys was compared in 40 patients (28 boys and 12 girls) using scintigraphy MAG-3 and dMRU. Differential renal function, as determined using both modalities, showed a difference of < 10% in 31 children and > 10% in 9 children. Calculation of the relative renal function using dMRU revealed an excellent correlation coefficient with renal scintigraphy MAG-3 for both kidneys. CONCLUSION Our findings demonstrated that dMRU is equivalent to scintigraphy MAG-3 for evaluating split renal function in patients with UPJO.
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Affiliation(s)
- Yousuf Al-Shaqsi
- Department of Pediatric Surgery, Sultan Qaboos University Hospital, Muscat 123, Oman
- Service de Chirurgie Viscérale et Urologie Pédiatrique, Hôpital Universitaire Robert-Debré, Assistance-Publique Hôpitaux de Paris, Paris 75019, France
- Centre de Références Maladies Rares, Malformations Rares des Voies Urinaires (MARVU), Paris 97019, France
| | - Matthieu Peycelon
- Service de Chirurgie Viscérale et Urologie Pédiatrique, Hôpital Universitaire Robert-Debré, Assistance-Publique Hôpitaux de Paris, Paris 75019, France
- Centre de Références Maladies Rares, Malformations Rares des Voies Urinaires (MARVU), Paris 97019, France
- Faculté de Médecine, Université de Paris, Paris 75006, France
| | - Annabel Paye-Jaouen
- Service de Chirurgie Viscérale et Urologie Pédiatrique, Hôpital Universitaire Robert-Debré, Assistance-Publique Hôpitaux de Paris, Paris 75019, France
- Centre de Références Maladies Rares, Malformations Rares des Voies Urinaires (MARVU), Paris 97019, France
| | - Elisabeth Carricaburu
- Service de Chirurgie Viscérale et Urologie Pédiatrique, Hôpital Universitaire Robert-Debré, Assistance-Publique Hôpitaux de Paris, Paris 75019, France
| | - Anca Tanase
- Centre de Références Maladies Rares, Malformations Rares des Voies Urinaires (MARVU), Paris 97019, France
- Service d’Imagerie Pédiatrique, Hôpital Universitaire Robert-Debré, Assistance-Publique Hôpitaux de Paris, Paris 75019, France
| | - Christine Grapin-Dagorno
- Service de Chirurgie Viscérale et Urologie Pédiatrique, Hôpital Universitaire Robert-Debré, Assistance-Publique Hôpitaux de Paris, Paris 75019, France
- Université Paris 13, Sorbonne Paris Cité, Paris 75013, France
| | - Alaa El-Ghoneimi
- Service de Chirurgie Viscérale et Urologie Pédiatrique, Hôpital Universitaire Robert-Debré, Assistance-Publique Hôpitaux de Paris, Paris 75019, France
- Centre de Références Maladies Rares, Malformations Rares des Voies Urinaires (MARVU), Paris 97019, France
- Faculté de Médecine, Université de Paris, Paris 75006, France
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Rashed AO, Gameraddin M, Fadulelmulla IA, Khardali AH, Alhazmi SA, Daghriri SH, Hakami LH, Madkhali AH, Foud AA, Alyami AS, Ageeli WA, Hendi AM, Madkhali Y, Alwadani B, Refaee TA, Majrashi NA. Sonographic Assessment of Renal Transplantation in Adult Saudi Patients: A Cross-Sectional Retrospective Study. Transplant Proc 2024; 56:75-81. [PMID: 38238237 DOI: 10.1016/j.transproceed.2023.11.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 10/06/2023] [Accepted: 11/13/2023] [Indexed: 02/20/2024]
Abstract
Kidney transplantation stands as a practical and cost-effective treatment option for end-stage renal disease patients, offering an improved quality of life with reduced morbidity when compared with hemodialysis. To evaluate the status of transplanted kidneys in Saudi patients, we conducted a retrospective single-center study at Jazan, Saudi Arabia, involving 46 adult renal recipients enrolled randomly from 2015 to December 2022. Using high-frequency ultrasound, we performed Duplex ultrasound examinations to assess renal allografts. The study revealed that the renal grafts exhibited normal length, with preserved cortical medullary differentiation (CMD) in 84.8% of cases and poor CMD in 15.2%. The echogenicity of the grafts remained normal in 69.6% of instances. Interestingly, we observed a significant rise in resistance index values as the graft duration increased (P = .04), whereas patients with abnormal creatinine levels displayed decreased peak systolic velocity and end-diastolic velocity. Notably, sonographic graft assessments unveiled complications, including perinephric fluid accumulation (8.7%), simple renal cysts (10.86%), hydronephrosis (8.7%), and one case of graft rejection. Receiver operating characteristics analysis for serum blood creatinine levels and abnormal parenchymal findings yielded fair to poor predictive accuracy, with varying sensitivity and specificity measures that lacked statistical significance. In conclusion, our study revealed that most Saudi renal transplant recipients exhibited grafts with normal echogenicity, preserved CMD, and limited perinephric fluid. This investigation provides valuable insights into sonographic changes and Doppler parameters of renal grafts, potentially aiding in the early detection of graft rejection and facilitating diagnostic and therapeutic planning.
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Affiliation(s)
- Altaf O Rashed
- Radiology Department, Samtah General Hospital, Ministry of Health, Jazan Health Affairs, Jazan, Saudi Arabia
| | - Moawia Gameraddin
- Department of Diagnostic Radiologic Technology, Faculty of Applied Medical Sciences, Taibah University, Al-Madinah, Saudi Arabia
| | - Ibtisam A Fadulelmulla
- Department of Diagnostic Radiology, College of Applied Medical Sciences, University of Hail, Hail, Saudi Arabia
| | - Abdullah H Khardali
- Radiology Department, King Fahad Central Hospital, Ministry of Health, Jazan Health Affairs, Jazan, Saudi Arabia
| | - Samar A Alhazmi
- Radiology Department, Mohmmed Bin Nasser Hospital, Ministry of Health, Jazan Health Affairs, Jazan, Saudi Arabia
| | - Sameerah H Daghriri
- Radiology Department, Samtah General Hospital, Ministry of Health, Jazan Health Affairs, Jazan, Saudi Arabia
| | - Laila H Hakami
- Radiology Department, Samtah General Hospital, Ministry of Health, Jazan Health Affairs, Jazan, Saudi Arabia
| | - Amaal H Madkhali
- Radiology Department, Samtah General Hospital, Ministry of Health, Jazan Health Affairs, Jazan, Saudi Arabia
| | - Afaf A Foud
- Radiology Department, Samtah General Hospital, Ministry of Health, Jazan Health Affairs, Jazan, Saudi Arabia
| | - Ali S Alyami
- Diagnostic Radiography Technology (DRT) Department, Faculty of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - Wael A Ageeli
- Diagnostic Radiography Technology (DRT) Department, Faculty of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - Ali M Hendi
- Diagnostic Radiography Technology (DRT) Department, Faculty of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia; Department of Radiology, Faculty of Medicine, Jazan University, Jazan, Saudi Arabia
| | - Yahia Madkhali
- Diagnostic Radiography Technology (DRT) Department, Faculty of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - Bandar Alwadani
- Diagnostic Radiography Technology (DRT) Department, Faculty of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - Turkey A Refaee
- Diagnostic Radiography Technology (DRT) Department, Faculty of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
| | - Naif A Majrashi
- Diagnostic Radiography Technology (DRT) Department, Faculty of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia.
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Kim PY, Shoghi A, Fananapazir G. Renal Transplantation: Immediate and Late Complications. Radiol Clin North Am 2023; 61:809-820. [PMID: 37495289 DOI: 10.1016/j.rcl.2023.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
Kidney grafts are the most common transplanted solid organ. To optimize graft survival, radiologists should be familiar with the anatomy and potential complications unique to transplanted kidneys. In addition to being able to recognize the imaging characteristics to diagnose etiologies of kidney graft dysfunction, an understanding of the pathophysiology is a key to narrowing the differential diagnosis. This article provides a summary of the most common complications based on broad categories of type of complication and posttransplant timing.
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Affiliation(s)
- Patrick Yoon Kim
- Department of Radiology, University of California Davis Health, Sacramento, CA 95817, USA
| | - Azarin Shoghi
- University of California, Davis School of Medicine, Sacramento, CA 95817, USA
| | - Ghaneh Fananapazir
- Department of Radiology, University of California Davis Health, Sacramento, CA 95817, USA.
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Leong SS, Jalalonmuhali M, Md Shah MN, Ng KH, Vijayananthan A, Hisham R, Wong JHD. Ultrasound shear wave elastography for the evaluation of renal pathological changes in adult patients. Br J Radiol 2023; 96:20220288. [PMID: 36802861 PMCID: PMC10078884 DOI: 10.1259/bjr.20220288] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 08/10/2022] [Accepted: 02/06/2023] [Indexed: 02/22/2023] Open
Abstract
OBJECTIVE Many studies have conflicting findings in using shear wave elastography (SWE) to assess renal fibrosis. This study reviews the use of SWE to evaluate pathological changes in native kidneys and renal allografts. It also tries to elucidate the confounding factors and care taken to ensure the results are consistent and reliable. METHODS The review was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Literature search was conducted in Pubmed, Web of Science and Scopus database up to 23 October 2021. To evaluate risk and bias applicability, the Cochrane risk-of bias tool and GRADE was used. The review was registered under PROSPERO CRD42021265303. RESULTS A total of 2921 articles were identified. 104 full texts were examined and 26 studies included in systematic review. 11 studies performed on native kidneys and 15 studies on transplanted kidney. A wide range of impact factors was found that affect the accuracy of SWE of renal fibrosis in adult patients. CONCLUSIONS Compared to point SWE, two-dimensional SWE with elastogram could enable better selection of the region of interest in kidneys, leading to reproducible results. Tracking waves were attenuated as the depth from skin to region of interest increased, therefore, SWE is not recommended for overweight or obese patients. Variable transducer forces might also affect SWE reproducibility, thus, training of operators to ensure consistent operator-dependent transducer forces may be helpful. ADVANCES IN KNOWLEDGE This review provides a holistic insight on the efficiency of using SWE in evaluating pathological changes in native and transplanted kidneys, thereby contributing to the knowledge of its utilisation in clinical practice.
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Affiliation(s)
- Sook Sam Leong
- Centre for Medical Imaging Studies, Faculty of Health Sciences, Universiti Teknologi MARA, Selangor, Malaysia
| | | | - Mohammad Nazri Md Shah
- Department of Biomedical Imaging, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
| | | | | | - Ranitha Hisham
- University Malaya Library, Universiti Malaya, Kuala Lumpur, Malaysia
| | - Jeannie Hsiu Ding Wong
- Department of Biomedical Imaging, Faculty of Medicine, Universiti Malaya, Kuala Lumpur, Malaysia
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Development and Evaluation of a Novel Radiotracer 125I-rIL-27 to Monitor Allotransplant Rejection by Specifically Targeting IL-27Rα. Mol Imaging 2023. [DOI: 10.1155/2023/4200142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
Noninvasive monitoring of allograft rejection is beneficial for the prognosis of patients with organ transplantation. Recently, IL-27/IL-27Rα was proved in close relation with inflammatory diseases, and 125I-anti-IL-27Rα mAb our group developed demonstrated high accumulation in the rejection of the allograft. However, antibody imaging has limitations in the imaging background due to its large molecular weight. Therefore, we developed a novel radiotracer (iodine-125-labeled recombinant IL-27) to evaluate the advantage in the targeting and imaging of allograft rejection. In vitro specific binding of 125I-rIL-27 was determined by saturation and competitive assay. Blood clearance, biodistribution, phosphor autoradioimaging, and IL-27Rα expression were studied on day 10 after transplantation (top period of allorejection). Our results indicated that 125I-rIL-27 could bind with IL-27Rα specifically and selectively in vitro. The blood clearance assay demonstrated fast blood clearance with 13.20 μl/h of 125I-rIL-27 staying in the blood after 24 h. The whole-body phosphor autoradiography and biodistribution assay indicated a higher specific uptake of 125I-rIL-27 and a clear radioimage in allograft than in syngraft at 24 h, while a similar result was obtained at 48 h in the group of 125I-anti-IL-27Rα mAb injection. Meanwhile, a higher expression of IL-27Rα was found in the allograft by Western blot. The accumulation of radioactivity of 125I-rIL-27 was highly correlated with the expression of IL-27Rα in the allograft. In conclusion, 125I-rIL-27 could be a promising probe for acutely monitoring allograft rejection with high specific binding towards IL-27Rα on allograft and low imaging background.
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Shin SH, Wendland MF, Wang J, Velasquez M, Vandsburger MH. Noninvasively differentiating acute and chronic nephropathies via multiparametric urea-CEST, nuclear Overhauser enhancement-CEST, and quantitative magnetization transfer MRI. Magn Reson Med 2023; 89:774-786. [PMID: 36226662 PMCID: PMC11027791 DOI: 10.1002/mrm.29477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 08/26/2022] [Accepted: 09/14/2022] [Indexed: 12/13/2022]
Abstract
PURPOSE Standardized blood tests often lack adequate sensitivity and specificity to capture the gradual progression of renal injuries. We suggest a multiparametric molecular MRI approach as a noninvasive tool for monitoring renal function loss and distinguishing different types of renal injuries. METHODS CEST and quantitative magnetization transfer (qMT) imaging were performed on cisplatin (n = 16) and aristolochic acid (AA)-induced nephropathy (n = 22) mouse models at 7T with an infusion of either saline or urea. Seven-pool Lorentzian fitting was applied for the analysis of CEST Z-spectra, and the T1 -corrected CEST contrast apparent exchange-dependent relaxation (AREX) from urea (+1 ppm) and two nuclear Overhauser enhancement (NOE) pools (-1.6 and -3.5 ppm) were measured. Similarly, qMT spectra were fitted into two-pool Ramani equation and the relative semi-solid macromolecular pool-size ratio was measured. Histology of mouse kidneys was performed to validate the MR findings. RESULTS AA model showed disrupted spatial gradients of urea in the kidney and significantly decreased NOE CEST and qMT contrast. The cisplatin model showed slightly decreased qMT contrast only. The orrelation of MR parameters to histological features showed that NOE CEST and qMT imaging are sensitive to both acute and chronic injuries, whereas urea CEST shows a significant correlation only to acute injuries. CONCLUSION These results indicate that our multiparametric approach allows comprehensive and totally noninvasive monitoring of renal function and histological changes for distinguishing different nephropathies.
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Affiliation(s)
- Soo Hyun Shin
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA
| | - Michael F. Wendland
- Berkeley Preclinical Imaging Core (BPIC), University of California, Berkeley, Berkeley, CA
| | - Jingshen Wang
- Department of Biostatistics, University of California, Berkeley, Berkeley, CA
| | - Mark Velasquez
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA
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Zhi R, Zhang XD, Hou Y, Jiang KW, Li Q, Zhang J, Zhang YD. RtNet: a deep hybrid neural network for the identification of acute rejection and chronic allograft nephropathy after renal transplantation using multiparametric MRI. Nephrol Dial Transplant 2022; 37:2581-2590. [PMID: 35020923 DOI: 10.1093/ndt/gfac005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Reliable diagnosis of the cause of renal allograft dysfunction is of clinical importance. The aim of this study is to develop a hybrid deep-learning approach for determining acute rejection (AR), chronic allograft nephropathy (CAN) and renal function in kidney-allografted patients by multimodality integration. METHODS Clinical and magnetic resonance imaging (MRI) data of 252 kidney-allografted patients who underwent post-transplantation MRI between December 2014 and November 2019 were retrospectively collected. An end-to-end convolutional neural network, namely RtNet, was designed to discriminate between AR, CAN and stable renal allograft recipient (SR), and secondarily, to predict the impaired renal graft function [estimated glomerular filtration rate (eGFR) ≤50 mL/min/1.73 m2]. Specially, clinical variables and MRI radiomics features were integrated into the RtNet, resulting in a hybrid network (RtNet+). The performance of the conventional radiomics model RtRad, RtNet and RtNet+ was compared to test the effect of multimodality interaction. RESULTS Out of 252 patients, AR, CAN and SR was diagnosed in 20/252 (7.9%), 92/252 (36.5%) and 140/252 (55.6%) patients, respectively. Of all MRI sequences, T2-weighted imaging and diffusion-weighted imaging with stretched exponential analysis showed better performance than other sequences. On pairwise comparison of resulting prediction models, RtNet+ produced significantly higher macro-area-under-curve (macro-AUC) (0.733 versus 0.745; P = 0.047) than RtNet in discriminating between AR, CAN and SR. RtNet+ performed similarly to the RtNet (macro-AUC, 0.762 versus 0.756; P > 0.05) in discriminating between eGFR ≤50 mL/min/1.73 m2 and >50 mL/min/1.73 m2. With decision curve analysis, adding RtRad and RtNet to clinical variables resulted in more net benefits in diagnostic performance. CONCLUSIONS Our study revealed that the proposed RtNet+ model owned a stable performance in revealing the cause of renal allograft dysfunction, and thus might offer important references for individualized diagnostics and treatment strategy.
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Affiliation(s)
- Rui Zhi
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Xiao-Dong Zhang
- Department of Radiology, Peking University First Hospital, Beijing, China
| | - Ying Hou
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Ke-Wen Jiang
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Qiao Li
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Jing Zhang
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Yu-Dong Zhang
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
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11
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Stigler J, Tiefenthaler M. Value and limitations of sonography in kidney transplant recipients with special attention to the resistive index - An update. FRONTIERS IN NEPHROLOGY 2022; 2:997839. [PMID: 37675004 PMCID: PMC10479591 DOI: 10.3389/fneph.2022.997839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 08/15/2022] [Indexed: 09/08/2023]
Abstract
Kidney transplantation has become the standard treatment for end-stage renal disease. Even though the success rates are high, early and late post-transplant complications remain a major clinical problem due to the risk of graft failure. Therefore, it is of highest interest to early diagnose post-transplant complications. Ultrasound with color coded Duplex analysis plays a crucial role in imaging mechanical and vascular complications. In this article, we give an update of the visualizable complications in kidney transplant recipients and discuss the value of resistive index (RI) measurement with its limitations in allograft rejection.
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Affiliation(s)
| | - Martin Tiefenthaler
- Department of Internal Medicine IV (Nephrology and Hypertension), Medical University Innsbruck, Innsbruck, Austria
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12
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Patel A, Sener A, Lee SY. Reversed diastolic flow in a renal transplant due to ureteric obstruction from intraluminal blood clot. JOURNAL OF CLINICAL ULTRASOUND : JCU 2022; 50:521-524. [PMID: 34634838 DOI: 10.1002/jcu.23079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 09/16/2021] [Accepted: 10/05/2021] [Indexed: 06/13/2023]
Abstract
Reversal of arterial diastolic flow is commonly considered a sign of transplant renal vein thrombosis until proven otherwise, with the differential including acute rejection, acute tubular necrosis, and perirenal hematoma. We discuss a case of a patient who presented with decreased urine output on the second postoperative day following living unrelated kidney transplantation. Doppler ultrasound was performed and demonstrated reversal of diastolic flow in the transplant renal artery. Prompt surgical exploration revealed intraluminal blood clot obstructing the ureter. To our knowledge, this is the first reported case of reversed diastolic flow secondary to ureteral obstruction by an intraluminal blood clot.
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Affiliation(s)
- Arbaaz Patel
- Michael G. DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Alp Sener
- Departments of Surgery and Microbiology and Immunology, Matthew Mailing Center for Translational Transplant Studies, Western University, London, Ontario, Canada
| | - Stefanie Y Lee
- Department of Radiology, McMaster University, Hamilton Health Sciences - Juravinski Hospital and Cancer Centre, Hamilton, Ontario, Canada
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13
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Paluszkiewicz P, Martuszewski A, Zaręba N, Wala K, Banasik M, Kepinska M. The Application of Nanoparticles in Diagnosis and Treatment of Kidney Diseases. Int J Mol Sci 2021; 23:ijms23010131. [PMID: 35008556 PMCID: PMC8745391 DOI: 10.3390/ijms23010131] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/16/2021] [Accepted: 12/21/2021] [Indexed: 12/12/2022] Open
Abstract
Nanomedicine is currently showing great promise for new methods of diagnosing and treating many diseases, particularly in kidney disease and transplantation. The unique properties of nanoparticles arise from the diversity of size effects, used to design targeted nanoparticles for specific cells or tissues, taking renal clearance and tubular secretion mechanisms into account. The design of surface particles on nanoparticles offers a wide range of possibilities, among which antibodies play an important role. Nanoparticles find applications in encapsulated drug delivery systems containing immunosuppressants and other drugs, in imaging, gene therapies and many other branches of medicine. They have the potential to revolutionize kidney transplantation by reducing and preventing ischemia-reperfusion injury, more efficiently delivering drugs to the graft site while avoiding systemic effects, accurately localizing and visualising the diseased site and enabling continuous monitoring of graft function. So far, there are known nanoparticles with no toxic effects on human tissue, although further studies are still needed to confirm their safety.
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Affiliation(s)
- Patrycja Paluszkiewicz
- Department of Emergency Medical Service, Wroclaw Medical University, Bartla 5, 50-367 Wroclaw, Poland;
| | - Adrian Martuszewski
- Department of Population Health, Division of Environmental Health and Occupational Medicine, Wroclaw Medical University, Mikulicza-Radeckiego 7, 50-368 Wroclaw, Poland;
| | - Natalia Zaręba
- Department of Pharmaceutical Biochemistry, Division of Biomedical and Environmental Analysis, Faculty of Pharmacy, Wroclaw Medical University, Borowska 211a, 50-556 Wrocław, Poland;
| | - Kamila Wala
- Faculty of Medicine, Wroclaw Medical University, Pasteura 1, 50-367 Wroclaw, Poland;
| | - Mirosław Banasik
- Department of Nephrology and Transplantation Medicine, Wroclaw Medical University, Borowska 213, 50-556 Wroclaw, Poland
- Correspondence: (M.B.); (M.K.); Tel.: +48-71-733-2500 (M.B.); +48-71-784-0171 (M.K.)
| | - Marta Kepinska
- Department of Pharmaceutical Biochemistry, Division of Biomedical and Environmental Analysis, Faculty of Pharmacy, Wroclaw Medical University, Borowska 211a, 50-556 Wrocław, Poland;
- Correspondence: (M.B.); (M.K.); Tel.: +48-71-733-2500 (M.B.); +48-71-784-0171 (M.K.)
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14
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Malhotra D, Dahl NK. An Unusual Cause of AKI in a Kidney Transplant Recipient. KIDNEY360 2021; 2:1869-1870. [PMID: 35373005 PMCID: PMC8785853 DOI: 10.34067/kid.0004332021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 07/02/2021] [Indexed: 02/04/2023]
Affiliation(s)
- Divyanshu Malhotra
- Department of Medicine, Section of Nephrology, Yale School of Medicine, Yale University, Connecticut
| | - Neera K. Dahl
- Department of Medicine, Section of Nephrology, Yale School of Medicine, Yale University, Connecticut
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15
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Hysi E, Kaur H, Young A. Evolving Medical Imaging Techniques for the Assessment of Delayed Graft Function: A Narrative Review. Can J Kidney Health Dis 2021; 8:20543581211048341. [PMID: 34707880 PMCID: PMC8544764 DOI: 10.1177/20543581211048341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 09/04/2021] [Indexed: 11/15/2022] Open
Abstract
Purpose of review Delayed graft function (DGF) is a significant complication that contributes to poorer graft function and shortened graft survival. In this review, we sought to evaluate the current and emerging role of medical imaging modalities in the assessment of DGF and how it may guide clinical management. Sources of information PubMed, Google Scholar, and ClinicalTrial.gov up until February 2021. Methods This narrative review first examined the pathophysiology of DGF and current clinical management. We then summarized relevant studies that utilized medical imaging to assess posttransplant renal complications, namely, DGF. We focused our attention on noninvasive, evolving imaging modalities with the greatest potential for clinical translation, including contrast-enhanced ultrasound (CEUS) and multiparametric magnetic resonance imaging (MRI). Key findings A kidney biopsy in the setting of DGF can be used to assess the degree of ischemic renal injury and to rule out acute rejection. Biopsies are accompanied by complications and may be limited by sampling bias. Early studies on CEUS and MRI have shown their potential to distinguish between the 2 most common causes of DGF (acute tubular necrosis and acute rejection), but they have generally included only small numbers of patients and have not kept pace with more recent technical advances of these imaging modalities. There remains unharnessed potential with CEUS and MRI, and more robust clinical studies are needed to better evaluate their role in the current era. Limitations The adaptation of emerging approaches for imaging DGF will depend on additional clinical trials to study the feasibility and diagnostic test characteristics of a given modality. This is limited by access to devices, technical competence, and the need for interdisciplinary collaborations to ensure that such studies are well designed to appropriately inform clinical decision-making.
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Affiliation(s)
- Eno Hysi
- Division of Nephrology, St. Michael's Hospital, Unity Health Toronto, ON, Canada.,Li Ka Shing Knowledge Institute, Keenan Research Centre for Biomedical Sciences, St. Michael's Hospital, Unity Health Toronto, ON, Canada
| | - Harmandeep Kaur
- Li Ka Shing Knowledge Institute, Keenan Research Centre for Biomedical Sciences, St. Michael's Hospital, Unity Health Toronto, ON, Canada
| | - Ann Young
- Division of Nephrology, St. Michael's Hospital, Unity Health Toronto, ON, Canada.,Li Ka Shing Knowledge Institute, Keenan Research Centre for Biomedical Sciences, St. Michael's Hospital, Unity Health Toronto, ON, Canada.,Division of Nephrology, Department of Medicine, University of Toronto, ON, Canada
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16
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Hinojosa-Gonzalez DE, Salgado-Garza G, Torres-Martinez M, Villegas-De Leon SU, Bueno-Gutierrez LC, Herrera-Carrillo FE, Gonzalez-Urquijo M, Segura Ibarra V, Fabiani MA, Flores-Villalba E. Endovascular Treatment of Transplant Renal Artery Stenosis: A Systematic Review and Meta-analysis. J Endovasc Ther 2021; 29:294-306. [PMID: 34399594 DOI: 10.1177/15266028211038593] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVE Endovascular treatment through either percutaneous transluminal angioplasty (PTA) alone or stenting has been previously used as a treatment for transplant renal artery stenosis (TRAS). This review aimed to investigate the results of endovascular treatment for renal artery stenosis in transplanted kidneys as compared with the outcomes of interventions, medical management, and graft survival in non-TRAS patients. METHODS A systematic review of PubMed, Google Scholar, Cochrane, and Scopus was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in which studies that reported outcomes of the treatment of TRAS via the endoluminal approach were identified, and their results were meta-analyzed. RESULTS Fifty-four studies with a total of 1522 patients were included. A significant reduction of serum creatinine level was found, favoring the stenting group, with a mean difference of 0.68 mg/dL (95% confidence interval (CI), 0.17-1.19; Z=2.60, p=0.0009). Comparison of pre- and post-intervention values of any intervention revealed a significant decrease in overall serum creatinine level (0.65 mg/dL; 95% CI, 0.40-0.90; Z=5.09, p=0.00001), overall blood pressure, with a mean difference of 11.12 mmHg (95% CI, 7.29-14.95; Z=5.59, p=0.00001), mean difference in the use of medications (0.77; 95% CI, 0.29-1.24; p=0.002), and peak systolic velocity (190.05; 95% CI, 128.41-251.69; p<0.00001). The comparison of serum creatinine level between endovascular interventions and best medical therapy favored endovascular intervention, with a mean difference of 0.23 mg/dL (95% CI, 0.14-0.32; Z=5.07, p<0.00001). Graft survival was similar between the treated patients and those without TRAS (hazard ratio, 0.98; 95% CI, 0.75-1.28; p=0.091). The overall pooled success rate was 89%, and the overall complication rate was 10.4%, with the most prevalent complication being arterial dissection. CONCLUSION The endovascular treatment of TRAS improves graft preservation and renal function and hemodynamic parameters. PTA + stenting appears to be a more effective option to PTA alone in the stabilization of renal function, with additional benefits from decreased restenosis rates. Further high-quality studies could expand on these findings.
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Affiliation(s)
| | - Gustavo Salgado-Garza
- Escuela de Medicina y Ciencias de la Salud, Tecnologico de Monterrey, Monterrey, NL, Mexico
| | | | | | | | | | | | - Victor Segura Ibarra
- Escuela de Medicina y Ciencias de la Salud, Tecnologico de Monterrey, Monterrey, NL, Mexico.,Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Monterrey, NL, Mexico
| | | | - Eduardo Flores-Villalba
- Escuela de Medicina y Ciencias de la Salud, Tecnologico de Monterrey, Monterrey, NL, Mexico.,Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Monterrey, NL, Mexico
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17
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Hai Y, Chong W, Liu JB, Forsberg F, Eisenbrey J. The Diagnostic Value of Contrast-Enhanced Ultrasound for Monitoring Complications After Kidney Transplantation-A Systematic Review and Meta-Analysis. Acad Radiol 2021; 28:1086-1093. [PMID: 32532638 DOI: 10.1016/j.acra.2020.05.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 05/07/2020] [Accepted: 05/07/2020] [Indexed: 01/18/2023]
Abstract
RATIONALE AND OBJECTIVES Contrast-enhanced ultrasound (CEUS) has increasingly gained acceptance in the postoperative evaluation of kidney-transplantation recipients. Our meta-analysis aims to evaluate the diagnostic accuracy of CEUS in identifying post-transplantation complications. MATERIALS AND METHODS PubMed, Scopus, Ovid Medline, and Cochrane databases were searched from their inception until February 28, 2020, for diagnostic test accuracy studies comparing CEUS to a reference standard for monitoring complications after kidney transplantation. A meta-analysis was conducted to calculate the pooled sensitivity, specificity, accuracy, and diagnostic odds ratio using a bivariate random effects model. Sensitivity analysis was performed using R software by stratifying the studies based on study design, sample size, age, and origin of the study to evaluate the influence of these factors on the overall effect. RESULTS Two independent reviewers analyzed 285 publications, out of which 29 were determined directly relevant and 12 (with a total of 542 cases) contained all required data for the meta-analysis. The overall sensitivity of included studies was estimated to be 0.86 (95% confidential interval (CI); 0.78--0.92). Similarly, the overall specificity was estimated to be 0.90 (95% CI; 0.82-0.94). Log diagnostic odds ratio was 4.25 (95% CI; 3.43-5.07), and the area under the curve of the pooled receiver operating characteristic was 0.94. Stratified sensitivity analyses showed study design, sample size, age group, and origin of the study had no significant impact on the overall diagnostic value of CEUS. CONCLUSION Evidence suggests that CEUS is a potentially effective and accurate method to evaluate a variety of complications such as rejection, vascular complications, and malignancies after kidney transplantation.
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18
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Luna C, Hassan F, Scortegagna E, Castillo RP. Analysis of the Peak Systolic Velocity in the Transplant Renal Artery Anastomosis to Determine Normal Values in Patients Without Graft Dysfunction. JOURNAL OF DIAGNOSTIC MEDICAL SONOGRAPHY 2021. [DOI: 10.1177/87564793211029897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective: The primary purpose is to define the mean renal artery anastomosis peak systolic velocity (RAA PSV) and the renal artery anastomosis to external iliac artery ratio (RAA-to-EIA) of renal transplant recipients without graft dysfunction. Moreover, to determine associations with type of vascular anastomosis and type of graft. Materials and Methods: This is a single-center retrospective analysis of kidney transplant recipients. Recorded variables included recipient age, type of vascular anastomosis, type of graft, RAA PSV, and external iliac artery PSV (EIA PSV). Such variables were evaluated on different postoperative follow-up periods. Results: There was a high degree of reliability between the RAA PSV and EIA PSV ( P < .001). The mean RAA PSV was 174 cm/s ± 72.9 cm/s with 95% confidence interval (CI) (162.2 cm/s-185.5 cm/s]. Conclusion: This study highlights the importance of determining the normal range of RAA PSV and showed that a high PSV does not necessarily indicate dysfunction.
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Affiliation(s)
- Cibele Luna
- Department of Radiology, University of Miami and Jackson Memorial Hospital, Miami, FL, USA
| | - Farooq Hassan
- Nova Southeastern University, Fort Lauderdale, FL, USA
| | - Eduardo Scortegagna
- Department of Radiology, University of Miami and Jackson Memorial Hospital, Miami, FL, USA
| | - Rosa Patricia Castillo
- Department of Radiology, University of Miami and Jackson Memorial Hospital, Miami, FL, USA
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19
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Yang WQ, Cui XL, Zhang M, Yuan XD, Ying L, Li FH, Li HL. Preoperative evaluation of iliac blood vessels for first kidney transplant recipients: Combination of conventional and contrast-enhanced ultrasonography. Clin Hemorheol Microcirc 2021; 78:139-149. [PMID: 33554892 DOI: 10.3233/ch-201054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To assess iliac blood vessels using conventional ultrasound (US) and contrast-enhanced ultrasonography (CEUS) before kidney transplantation (KT) and determine whether US findings related to post-transplant outcomes. METHODS A total of 119 patients received US and CEUS before KT waiting-list acceptance. The preoperative iliac blood hemodynamics and vascular conditions were evaluated. The operative strategy and follow-up outcomes were recorded. Logistic regression and correlation analysis were used. The accuracy in determining the patency of iliac blood vessels was calculated before and after the injection of contrast materials. RESULTS CEUS can help to significantly improve the visualization of the internal iliac artery, but there was no significant correlation with post-transplant outcomes. In terms of accuracy, there were significant differences in determining the patency of internal iliac arteries between conventional US and CEUS (60.5% and 100%, p < 0.001). The surgical strategy of one patient was regulated and two patients were excluded from KT according to US findings. CONCLUSIONS Compared with conventional US, CEUS helps to improve the visualization of the internal iliac artery. Conventional US and CEUS have the potential to serve as effective methods to evaluate anatomy and hemodynamics of iliac vessels and have a potential value while defining clinical algorithms in surgery decision-making.
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Affiliation(s)
- Wen-Qi Yang
- Department of Ultrasound, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Xiao-Lan Cui
- Department of Ultrasound, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Ming Zhang
- Department of Urology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Xiao-Dong Yuan
- Department of Urology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Liang Ying
- Department of Urology, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Feng-Hua Li
- Department of Ultrasound, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Hong-Li Li
- Department of Ultrasound, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
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20
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Wahab SA, Abraham B, Bailey A, Choe KA. Imaging findings of en bloc simultaneous liver-kidney transplantation. Abdom Radiol (NY) 2021; 46:1876-1890. [PMID: 33083870 DOI: 10.1007/s00261-020-02824-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 10/01/2020] [Accepted: 10/10/2020] [Indexed: 10/23/2022]
Abstract
Simultaneous liver-kidney transplantations (SLKTs) are increasing in incidence, and the en bloc surgical approach is associated with a unique spectrum of vascular complications. En bloc SLKTs have a common arterial supply from the celiac axis and post-operative assessment with Doppler ultrasound can help to localize vascular lesions as either proximal in the shared arterial supply or distal in the organ-specific arteries. Venous complications predominantly include thrombosis or stenosis of the portal vein, hepatic veins, renal vein, or IVC, but have a much lower incidence. Radiologists familiar with the post-operative anatomy and complications can provide meaningful and accurate assessment to help direct clinical care. The purpose of this article is to provide a targeted review of SLKT, review the post-surgical anatomy associated with en bloc SLKT, and review the imaging evaluation of vascular complications associated with SLKT.
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21
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Maly S, Janousek L, Bortel R, Sebek J, Hospodka J, Skapa J, Fronek J. NIRS-based monitoring of kidney graft perfusion. PLoS One 2020; 15:e0243154. [PMID: 33264371 PMCID: PMC7710057 DOI: 10.1371/journal.pone.0243154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 11/16/2020] [Indexed: 12/28/2022] Open
Abstract
Introduction Acute early vascular complications are rare, but serious complications after kidney transplantation. They often result in graft loss. For this reason, shortening the diagnostic process is crucial. Currently, it is standard procedure to monitor renal graft perfusion using Doppler ultrasound (DU). With respect to acute vascular complications, the main disadvantage of this type of examination is its periodicity. It would be of great benefit if graft blood perfusion could be monitored continuously during the early postoperative period. It appears evident that a well-designed near infrared spectroscopy (NIRS) monitoring system could prove very useful during the early post-transplantation period. Its role in the immediate diagnosis of vascular complications could result in a significant increase in graft salvage, thus improving the patient’s overall quality of life and lowering morbidity and mortality for renal graft recipients. The aim of this study was to design, construct and test such a monitoring system. Materials and methods We designed a rough NIRS-based system prototype and prepared a two-stage laboratory experiment based on a laboratory pig model. In the first stage, a total of 10 animals were used to verify and optimize the technical aspects and functionality of the prototype sensor by testing it on the animal kidneys in-vivo. As a result of these tests, a more specific prototype was designed. During the second stage, we prepared a unique laboratory model of a pig kidney autotransplantation and tested the system for long-term functionality on a group of 20 animals. Overall sensitivity and specificity were calculated, and a final prototype was prepared and completed with its own analytic software and chassis. Results We designed and constructed a NIRS-based system for kidney graft perfusion monitoring. The measurement system provided reliable performance and 100% sensitivity when detecting acute diminished blood perfusion of the transplanted kidneys in laboratory conditions. Conclusion The system appears to be a useful tool for diagnosing diminished blood perfusion of kidney transplants during the early postoperative period. However, further testing is still required. We believe that applying our method in current human transplantation medicine is feasible, and we are confident that our prototype is ready for human testing.
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Affiliation(s)
- Stepan Maly
- Transplant Surgery Department, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- First Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
- * E-mail:
| | - Libor Janousek
- Transplant Surgery Department, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- First Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
| | - Radoslav Bortel
- Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic
| | - Jan Sebek
- Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic
| | - Jiri Hospodka
- Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic
| | - Jiri Skapa
- Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic
| | - Jiri Fronek
- Transplant Surgery Department, Institute for Clinical and Experimental Medicine, Prague, Czech Republic
- Department of Anatomy, Second Faculty of Medicine, Charles University in Prague, Prague, Czech Republic
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22
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Shin SH, Wendland MF, Vandsburger MH. Delayed urea differential enhancement CEST (dudeCEST)-MRI with T 1 correction for monitoring renal urea handling. Magn Reson Med 2020; 85:2791-2804. [PMID: 33180343 DOI: 10.1002/mrm.28583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 12/12/2022]
Abstract
PURPOSE We demonstrate a method of delayed urea differential enhancement CEST for probing urea recycling action of the kidney using expanded multi-pool Lorentzian fitting and apparent exchange-dependent relaxation compensation. METHODS T1 correction of urea CEST contrast by apparent exchange-dependent relaxation was tested in phantoms. Nine mice were scanned at 7 Tesla following intraperitoneal injection of 2M 150 μL urea, and later saline. T1 maps and Z-spectra were acquired before and 20 and 40 min postinjection. Z-spectra were fit to a 7-pool Lorentzian model for CEST quantification and compared to urea assay of kidney homogenate. Renal injury was induced by aristolochic acid in 7 mice, and the same scan protocol was performed. RESULTS Apparent exchange-dependent relaxation corrected for variable T1 times in phantoms. Urea CEST contrast at +1 ppm increased significantly at both time points following urea injection in the inner medulla and papilla. When normalizing the postinjection urea CEST contrast to the corresponding baseline value, both urea and saline injection resulted in identical fold changes in urea CEST contrast. Urea assay of kidney homogenate showed a significant correlation to both apparent exchange-dependent relaxation (R2 = 0.4687, P = .0017) and non-T1 -corrected Lorentzian amplitudes (R2 = 0.4964, P = .0011). Renal injury resulted in increased T1 time in the cortex and reduced CEST contrast change upon urea and saline infusion. CONCLUSION Delayed urea enhancement following infusion can provide insight into renal urea handling. In addition, changes in CEST contrast at 1.0 ppm following saline infusion may provide insight into renal function.
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Affiliation(s)
- Soo Hyun Shin
- Department of Bioengineering, University of California, Berkeley, Berkeley, California, USA
| | - Michael F Wendland
- Berkeley Preclinical Imaging Core (BPIC), University of California, Berkeley, Berkeley, California, USA
| | - Moriel H Vandsburger
- Department of Bioengineering, University of California, Berkeley, Berkeley, California, USA
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Sugi MD, Joshi G, Maddu KK, Dahiya N, Menias CO. Imaging of Renal Transplant Complications throughout the Life of the Allograft: Comprehensive Multimodality Review. Radiographics 2020; 39:1327-1355. [PMID: 31498742 DOI: 10.1148/rg.2019190096] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The kidney is the most commonly transplanted solid organ. Advances in surgical techniques, immunosuppression regimens, surveillance imaging, and histopathologic diagnosis of rejection have allowed prolonged graft survival times. However, the demand for kidneys continues to outgrow the available supply, and there are efforts to increase use of donor kidneys with moderate- or high-risk profiles. This highlights the importance of evaluating the renal transplant patient in the context of both donor and recipient risk factors. Radiologists play an integral role within the multidisciplinary team in care of the transplant patient at every stage of the transplant process. In the immediate postoperative period, duplex US is the modality of choice for evaluating the renal allograft. It is useful for establishing a baseline examination for comparison at future surveillance imaging. In the setting of allograft dysfunction, advanced imaging techniques including MRI or contrast-enhanced US may be useful for providing a more specific diagnosis and excluding nonrejection causes of renal dysfunction. When a pathologic diagnosis is deemed necessary to guide therapy, US-guided biopsy is a relatively low-risk, safe procedure. The range of complications of renal transplantation can be organized temporally in relation to the time since surgery and/or according to disease categories, including immunologic (rejection), surgical or iatrogenic, vascular, urinary, infectious, and neoplastic complications. The unique heterotopic location of the renal allograft in the iliac fossa predisposes it to a specific set of complications. As imaging features of infection or malignancy may be nonspecific, awareness of the patient's risk profile and time since transplantation can be used to assign the probability of a certain diagnosis and thus guide more specific diagnostic workup. It is critical to understand variations in vascular anatomy, surgical technique, and independent donor and recipient risk factors to make an accurate diagnosis and initiate appropriate treatment.©RSNA, 2019.
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Affiliation(s)
- Mark D Sugi
- From the Department of Radiology, Mayo Clinic, Scottsdale, Ariz (M.D.S., N.D., C.O.M.); and Departments of Radiology and Imaging Sciences (G.J., K.K.M.) and Emergency Medicine (G.J., K.K.M.), Emory University School of Medicine, Atlanta, Ga
| | - Gayatri Joshi
- From the Department of Radiology, Mayo Clinic, Scottsdale, Ariz (M.D.S., N.D., C.O.M.); and Departments of Radiology and Imaging Sciences (G.J., K.K.M.) and Emergency Medicine (G.J., K.K.M.), Emory University School of Medicine, Atlanta, Ga
| | - Kiran K Maddu
- From the Department of Radiology, Mayo Clinic, Scottsdale, Ariz (M.D.S., N.D., C.O.M.); and Departments of Radiology and Imaging Sciences (G.J., K.K.M.) and Emergency Medicine (G.J., K.K.M.), Emory University School of Medicine, Atlanta, Ga
| | - Nirvikar Dahiya
- From the Department of Radiology, Mayo Clinic, Scottsdale, Ariz (M.D.S., N.D., C.O.M.); and Departments of Radiology and Imaging Sciences (G.J., K.K.M.) and Emergency Medicine (G.J., K.K.M.), Emory University School of Medicine, Atlanta, Ga
| | - Christine O Menias
- From the Department of Radiology, Mayo Clinic, Scottsdale, Ariz (M.D.S., N.D., C.O.M.); and Departments of Radiology and Imaging Sciences (G.J., K.K.M.) and Emergency Medicine (G.J., K.K.M.), Emory University School of Medicine, Atlanta, Ga
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Alduraibi AK, Fathala A. Ischemic reperfusion injury of renal transplant mimics acute rejection on renal scintigraphy in early post-operative period. Urol Case Rep 2020; 30:101122. [PMID: 32181143 PMCID: PMC7066220 DOI: 10.1016/j.eucr.2020.101122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 01/09/2020] [Indexed: 01/20/2023] Open
Abstract
Renal scintigraphy of a renal graft is a non-invasive imaging used to evaluate renal graft dysfunction in relay postoperative period. We presented the case of a 42-year-old man when underwent renal transplantation and developed anuria with severe renal impairment. Renal scintigraphy yielded no visualization of the renal graft. Subsequently, the patient underwent an exploratory laparotomy. The graft was found to have normal perfusion, and a surgical biopsy suggestive of an acute perfusion injury and mild tubular necrosis. The patient recovered with conservative therapy. This case highlights a common limitation of renal scintigraphy in a post-renal-transplantation patient with severe renal impairment.
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Affiliation(s)
- Alaa Khalid Alduraibi
- Department of Radiology & Imaging, College of Medicine, Qassim University, Buraidah, Al Qassim, Saudi Arabia
| | - Ahmed Fathala
- Department of Radiology, King Faisal Specialist Hospital & Research Center, Riyadh, 11211, Saudi Arabia
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25
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Qi R, Qi G, Zhu D, Wang J. Diagnosis and Treatment of Early Transplant Renal Artery Stenosis: Experience From a Center in Eastern China. Transplant Proc 2020; 52:179-185. [PMID: 31901326 DOI: 10.1016/j.transproceed.2019.11.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/12/2019] [Accepted: 11/02/2019] [Indexed: 01/20/2023]
Abstract
Few studies have focused on the clinical characteristics of transplant renal artery stenosis (TRAS) with early onset. Sixteen cases diagnosed with TRAS in our center from January 2014 to August 2018 were retrospectively analyzed. Sixteen transplant patients without TRAS were selected as controls. The median diagnostic time for TRAS was 47.5 days after transplantation. No significant difference was observed between the TRAS group and the control group. The serum creatinine level (Scr), estimated glomerular filtration rate, systolic/diastolic blood pressure, graft artery peak systolic velocity (PSV), and resistive index of intersegmental artery (RI-ISA) between the 2 groups were (5.55 ± 3.49) and (1.89 ± 0.85) mg/dL; (17.83 ± 14.94) and (49.39 ± 19.96) mL/min; (143.50 ± 9.49)/(86.14 ± 7.38) and (130.38 ± 18.86)/(82.81 ± 12.52) mm Hg; (3.39 ± 1.57) and (1.31 ± 0.51) m/s; and (0.51 ± 0.10) and (0.67 ± 0.13), respectively. All showed statistical significance except the diastolic blood pressure. The Scr, estimated glomerular filtration rate, systolic/diastolic blood pressure, graft artery PSV, and RI-ISA in the TRAS group prior and after treatment were (5.55 ± 3.49) and (3.20 ± 1.50) mg/dL; (17.83 ± 14.94) and (25.60 ± 13.29) mL/min; (143.50 ± 9.49)/(86.14 ± 7.38) and (128.07 ± 16.16)/(75.71 ± 7.56) mm Hg; (3.39 ± 1.57) and (2.00 ± 1.04) m/s; and (0.51 ± 0.10) and (0.61 ± 0.10); all showed statistical significance. Receiver operating characteristic analysis showed an area under curve of 0.8616 for PSV and 0.8535 for RI-ISA in diagnosing TRAS. Patients with TRAS in our center showed a unique characteristic of early onset. The most prominent clinical symptom of TRAS is increasing Scr level instead of refractory hypertension. Screening of color Doppler flow imaging with a graft artery PSV >2.5 m/s and RI-ISA <0.5 could yield a preliminary diagnosis of TRAS. Percutaneous transluminal angioplasty/stenting could effectively improve allograft function as well as color Doppler flow imaging indexes.
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Affiliation(s)
- Ruochen Qi
- Department of Urology, Zhongshan Hospital, Fudan University, Shanghai, P.R. China; Shanghai Medical College, Fudan University Shanghai, P.R. China; Shanghai Key Laboratory of Organ Transplantation, Shanghai, P. R. China
| | - Guisheng Qi
- Department of Urology, Zhongshan Hospital, Fudan University, Shanghai, P.R. China; Shanghai Key Laboratory of Organ Transplantation, Shanghai, P. R. China
| | - Dong Zhu
- Department of Urology, Zhongshan Hospital, Fudan University, Shanghai, P.R. China; Shanghai Key Laboratory of Organ Transplantation, Shanghai, P. R. China
| | - Jina Wang
- Department of Urology, Zhongshan Hospital, Fudan University, Shanghai, P.R. China; Shanghai Key Laboratory of Organ Transplantation, Shanghai, P. R. China.
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26
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Favi E, Raison N, Ambrogi F, Delbue S, Clementi MC, Lamperti L, Perego M, Bischeri M, Ferraresso M. Systematic review of ablative therapy for the treatment of renal allograft neoplasms. World J Clin Cases 2019; 7:2487-2504. [PMID: 31559284 PMCID: PMC6745334 DOI: 10.12998/wjcc.v7.i17.2487] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 08/01/2019] [Accepted: 08/20/2019] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND To date, there are no guidelines on the treatment of solid neoplasms in the transplanted kidney. Historically, allograft nephrectomy has been considered the only reasonable option. More recently, nephron-sparing surgery (NSS) and ablative therapy (AT) have been proposed as alternative procedures in selected cases.
AIM To review outcomes of AT for the treatment of renal allograft tumours.
METHODS We conducted a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009 Checklist. PubMed was searched in March 2019 without time restrictions for all papers reporting on radiofrequency ablation (RFA), cryoablation (CA), microwave ablation (MWA), high-intensity focused ultrasound (HIFU), and irreversible electroporation (IRE) of solid tumours of the kidney allograft. Only original manuscripts describing actual cases and edited in English were considered. All relevant articles were accessed in full text. Additional searches included all pertinent references. Selected studies were also assessed for methodological quality using a tool based on a modification of the Newcastle Ottawa scale. Data on recipient characteristics, transplant characteristics, disease characteristics, treatment protocols, and treatment outcomes were extracted and analysed. Given the nature and the quality of the studies available (mostly retrospective case reports and small retrospective uncontrolled case series), a descriptive summary was provided.
RESULTS Twenty-eight relevant studies were selected describing a total of 100 AT procedures in 92 patients. Recipient age at diagnosis ranged from 21 to 71 years whereas time from transplant to diagnosis ranged from 0.1 to 312 mo. Most of the neoplasms were asymptomatic and diagnosed incidentally during imaging carried out for screening purposes or for other clinical reasons. Preferred diagnostic modality was Doppler-ultrasound scan followed by computed tomography scan, and magnetic resonance imaging. Main tumour types were: papillary renal cell carcinoma (RCC) and clear cell RCC. Maximal tumour diameter ranged from 5 to 55 mm. The vast majority of neoplasms were T1a N0 M0 with only 2 lesions staged T1b N0 M0. Neoplasms were managed by RFA (n = 78), CA (n = 15), MWA (n = 3), HIFU (n = 3), and IRE (n = 1). Overall, 3 episodes of primary treatment failure were reported. A single case of recurrence was identified. Follow-up ranged from 1 to 81 mo. No cancer-related deaths were observed. Complication rate was extremely low (mostly < 10%). Graft function remained stable in the majority of recipients. Due to the limited sample size, no clear benefit of a single procedure over the other ones could be demonstrated.
CONCLUSION AT for renal allograft neoplasms represents a promising alternative to radical nephrectomy and NSS in carefully selected patients. Properly designed clinical trials are needed to validate this therapeutic approach.
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Affiliation(s)
- Evaldo Favi
- Renal Transplantation, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
| | - Nicholas Raison
- MRC Centre for Transplantation, King’s College London, London WC2R 2LS, United Kingdom
| | - Federico Ambrogi
- Department of Clinical Sciences and Community Health, University of Milan, Milan 20122, Italy
| | - Serena Delbue
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan 20100, Italy
| | - Maria Chiara Clementi
- Renal Transplantation, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
| | - Luca Lamperti
- Renal Transplantation, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
| | - Marta Perego
- Renal Transplantation, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
| | - Matteo Bischeri
- Renal Transplantation, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
| | - Mariano Ferraresso
- Renal Transplantation, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan 20122, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan 20122, Italy
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27
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Shin SH, Wendland MF, Zhang B, Tran A, Tang A, Vandsburger MH. Noninvasive imaging of renal urea handling by CEST-MRI. Magn Reson Med 2019; 83:1034-1044. [PMID: 31483529 DOI: 10.1002/mrm.27968] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 08/01/2019] [Accepted: 08/04/2019] [Indexed: 12/13/2022]
Abstract
PURPOSE Renal function is characterized by concentration of urea for removal in urine. We tested urea as a CEST-MRI contrast agent for measurement of the concentrating capacity of distinct renal anatomical regions. METHODS The CEST contrast of urea was examined using phantoms with different concentrations and pH levels. Ten C57BL/6J mice were scanned twice at 7 T, once following intraperitoneal injection of 2M 150 µL urea and separately following an identical volume of saline. Kidneys were segmented into regions encompassing the cortex, outer medulla, and inner medulla and papilla to monitor spatially varying urea concentration. Z-spectra were acquired before and 20 minutes after injection, with dynamic scanning of urea handling performed in between via serial acquisition of CEST images acquired following saturation at +1 ppm. RESULTS Phantom experiments revealed concentration and pH-dependent CEST contrast of urea that was both acid- and base-catalyzed. Z-spectra acquired before injection showed significantly higher CEST contrast in the inner medulla and papilla (2.3% ± 1.9%) compared with the cortex (0.15% ± 0.75%, P = .011) and outer medulla (0.12% ± 0.58%, P = .008). Urea infusion increased CEST contrast in the inner medulla and papilla by 2.1% ± 1.9% (absolute), whereas saline infusion decreased CEST contrast by -0.5% ± 2.0% (absolute, P = .028 versus urea). Dynamic scanning revealed that thermal drift and diuretic status are confounding factors. CONCLUSION Urea CEST has a potential of monitoring renal function by capturing the spatially varying urea concentrating ability of the kidneys.
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Affiliation(s)
- Soo Hyun Shin
- Department of Bioengineering, University of California, Berkeley, Berkeley, California
| | - Michael F Wendland
- Berkeley Preclinical Imaging Core, University of California, Berkeley, Berkeley, California
| | - Brandon Zhang
- Department of Bioengineering, University of California, Berkeley, Berkeley, California
| | - An Tran
- Department of Bioengineering, University of California, Berkeley, Berkeley, California
| | - Albert Tang
- Department of Bioengineering, University of California, Berkeley, Berkeley, California
| | - Moriel H Vandsburger
- Department of Bioengineering, University of California, Berkeley, Berkeley, California
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28
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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: 32] [Impact Index Per Article: 6.4] [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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29
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Pérez Civantos D, Muñoz Cantero A, Robles Marcos M, Fariñas Seijas H, Santiago Triviño M, Pérez Frutos M, Jimeno Torres B. Utility of Basal Regional Oximetry Saturation for the Diagnosis of Acute Tubular Necrosis in the Early Postoperative Period Following Kidney Transplantation. Transplant Proc 2019; 51:328-333. [DOI: 10.1016/j.transproceed.2018.12.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 11/29/2018] [Accepted: 12/09/2018] [Indexed: 12/11/2022]
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30
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Abstract
Renal transplantation is the therapy of choice for patients with end-stage renal diseases. Improvement of immunosuppressive therapy has significantly increased the half-life of renal allografts over the past decade. Nevertheless, complications can still arise. An early detection of allograft dysfunction is mandatory for a good outcome. New advances in magnetic resonance imaging (MRI) have enabled the noninvasive assessment of different functional renal parameters in addition to anatomic imaging. Most of these techniques were widely tested on renal allografts in past decades and a lot of clinical data are available. The following review summarizes the comprehensive, functional MRI techniques for the noninvasive assessment of renal allograft function and highlights their potential for the investigations of different etiologies of graft dysfunction.
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31
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Sławińska A, Serafin Z, Zawada E, Białecki M, Wypych K, Woderska A, Słupski M, Włodarczyk Z. Noninvasive evaluation of renal tissue oxygenation with blood oxygen level-dependent magnetic resonance imaging early after transplantation has a limited predictive value for the delayed graft function. Pol J Radiol 2018; 83:e389-e393. [PMID: 30655915 PMCID: PMC6334089 DOI: 10.5114/pjr.2018.78622] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Accepted: 07/05/2018] [Indexed: 12/30/2022] Open
Abstract
PURPOSE The aim of this study was to evaluate the feasibility of renal oxygenation assessment using blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) in the early period after kidney transplantation and to estimate its prognostic value for delayed graft function. MATERIAL AND METHODS Examinations were performed in 50 subjects: 40 patients within a week after the kidney transplantation and 10 healthy controls, using T2*-weighted sequence. Measurements in transplant patients were correlated to basic laboratory parameters in the early period after transplantation and at follow-up. RESULTS Examinations of seven patients (18%) were rejected due to their poor technical quality. Mean R2* values in transplant recipients were lower than in controls (11.6 vs. 15.9 Hz; p = 0.0001). An R2* value of 0.28 Hz was calculated as the minimal detectable change. There was no relation between R2* values and laboratory parameters. However, patients eGFR ≥ 40 ml/min/1.73 m2 presented higher R2* values than recipients eGFR < 40 ml/min/1.73 m2 (12.0 vs. 11.1 Hz; p = 0.0189). In ROC analysis R2* of ≤ 11.7 predicted an early reduced graft function with 0.82 sensitivity and 56% specificity (AUC = 0.708; p = 0.024) but was not useful for delayed graft function prediction (p > 0.7). CONCLUSIONS Evaluation of renal graft oxygenation using BOLD MRI is technically challenging in the early period after transplantation. An R2* value of 0.28 Hz may in practice be considered as the minimal detectable change. The delayed graft function seems not to be dependent on early oxygenation values. Further, large-scale studies are necessary to confirm the latter observation.
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Affiliation(s)
- Agata Sławińska
- Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Zbigniew Serafin
- Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Elżbieta Zawada
- Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Marcin Białecki
- Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Katarzyna Wypych
- Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Aleksandra Woderska
- Department of General and Transplant Surgery, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Maciej Słupski
- Department of Hepatobiliary and General Surgery, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Zbigniew Włodarczyk
- Department of General and Transplant Surgery, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
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32
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Taffel MT, Nikolaidis P, Beland MD, Blaufox MD, Dogra VS, Goldfarb S, Gore JL, Harvin HJ, Heilbrun ME, Heller MT, Khatri G, Preminger GM, Purysko AS, Smith AD, Wang ZJ, Weinfeld RM, Wong-You-Cheong JJ, Remer EM, Lockhart ME. ACR Appropriateness Criteria ® Renal Transplant Dysfunction. J Am Coll Radiol 2018; 14:S272-S281. [PMID: 28473084 DOI: 10.1016/j.jacr.2017.02.034] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 02/20/2017] [Accepted: 02/21/2017] [Indexed: 02/06/2023]
Abstract
Renal transplantation is the treatment of choice in patients with end-stage renal disease because the 5-year survival rates range from 72% to 99%. Although graft survival has improved secondary to the introduction of newer immunosuppression drugs and the advancements in surgical technique, various complications still occur. Ultrasound is the first-line imaging modality for the evaluation of renal transplants in the immediate postoperative period and for long-term follow-up. In addition to depicting many of the potential complications of renal transplantation, ultrasound can also guide therapeutic interventions. Nuclear medicine studies, CT, and MRI are often helpful as complementary examinations for specific indications. Angiography remains the reference standard for vascular complications and is utilized to guide nonsurgical intervention. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
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Affiliation(s)
| | - Myles T Taffel
- Principal Author, George Washington University Hospital, Washington, District of Columbia.
| | - Paul Nikolaidis
- Panel Vice-chair, Northwestern University, Chicago, Illinois
| | | | - M Donald Blaufox
- Albert Einstein College of Medicine, Bronx, New York; Society of Nuclear Medicine and Molecular Imaging
| | - Vikram S Dogra
- University of Rochester Medical Center, Rochester, New York
| | - Stanley Goldfarb
- University of Pennsylvania School of Medicine, Philadelphia; Pennsylvania, American Society of Nephrology
| | - John L Gore
- University of Washington, Seattle, Washington; American Urological Association
| | | | | | | | | | - Glenn M Preminger
- Duke University Medical Center, Durham, North Carolina; American Urological Association
| | | | - Andrew D Smith
- The University of Mississippi Medical Center, Jackson, Mississippi
| | - Zhen J Wang
- University of California San Francisco School of Medicine, San Francisco, California
| | - Robert M Weinfeld
- Oakland University William Beaumont School of Medicine, Troy, Michigan
| | | | | | - Mark E Lockhart
- Panel Chair, University of Alabama at Birmingham, Birmingham, Alabama
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33
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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: 10] [Impact Index Per Article: 1.7] [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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El-Diasty MT, Gaballa G, Gad HM, Borg MA, Abou-Elghar ME, Sheir KZ, El-Diasty TA. Evaluation of CT perfusion parameters for assessment of split renal function in healthy donors. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2016. [DOI: 10.1016/j.ejrnm.2016.07.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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Goldberg RJ, Weng FL, Kandula P. Acute and Chronic Allograft Dysfunction in Kidney Transplant Recipients. Med Clin North Am 2016; 100:487-503. [PMID: 27095641 DOI: 10.1016/j.mcna.2016.01.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Allograft dysfunction after a kidney transplant is often clinically asymptomatic and is usually detected as an increase in serum creatinine level with corresponding decrease in glomerular filtration rate. The diagnostic evaluation may include blood tests, urinalysis, transplant ultrasonography, radionuclide imaging, and allograft biopsy. Whether it occurs early or later after transplant, allograft dysfunction requires prompt evaluation to determine its cause and subsequent management. Acute rejection, medication toxicity from calcineurin inhibitors, and BK virus nephropathy can occur early or later. Other later causes include transplant glomerulopathy, recurrent glomerulonephritis, and renal artery stenosis.
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Affiliation(s)
- Ryan J Goldberg
- Renal & Pancreas Transplant Division, Saint Barnabas Medical Center, Livingston, NJ, USA.
| | - Francis L Weng
- Renal & Pancreas Transplant Division, Saint Barnabas Medical Center, Livingston, NJ, USA
| | - Praveen Kandula
- Renal & Pancreas Transplant Division, Saint Barnabas Medical Center, Livingston, NJ, USA
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Stanescu AL, Hryhorczuk AL, Chang PT, Lee EY, Phillips GS. Pediatric Abdominal Organ Transplantation. Radiol Clin North Am 2016; 54:281-302. [DOI: 10.1016/j.rcl.2015.09.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Abstract
One of the principal roles of a nephrologist is to closely monitor renal transplant allograft function and promptly evaluate any dysfunction. Renal transplant sonography has a major role in this assessment process given its ability to easily define renal transplant anatomy and surrounding structures. Abnormalities can be extrarenal or involve vascular, parenchymal and urological components of the graft and these can acutely or chronically influence graft function and survival. Procedural guidance as is required during allograft biopsy, as well as routine surveillance and screening for post transplant complications such as malignancy are also important applications of ultrasound in the management of renal transplant recipients. This article outlines key ultrasound findings and applications in renal transplantation from the clinician's perspective.
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Affiliation(s)
- Khai Gene Leong
- Department of Nephrology Monash Health Clayton Victoria Australia
| | - Peter Coombs
- Monash Imaging C/-Monash HealthClaytonVictoriaAustralia; Department of Medical ImagingRadiation Sciences Monash UniversityClaytonVictoriaAustralia
| | - John Kanellis
- Department of Nephrology Monash HealthClaytonVictoriaAustralia; Centre for Inflammatory DiseasesDepartment of Medicine Monash UniversityClaytonVictoriaAustralia
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Wang YT, Li YC, Yin LL, Pu H, Chen JY. Functional assessment of transplanted kidneys with magnetic resonance imaging. World J Radiol 2015; 7:343-349. [PMID: 26516431 PMCID: PMC4620115 DOI: 10.4329/wjr.v7.i10.343] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 08/17/2015] [Accepted: 09/08/2015] [Indexed: 02/06/2023] Open
Abstract
Kidney transplantation has emerged as the treatment of choice for many patients with end-stage renal disease, which is a significant cause of morbidity and mortality. Given the shortage of clinically available donor kidneys and the significant incidence of allograft dysfunction, a noninvasive and accurate assessment of the allograft renal function is critical for postoperative management. Prompt diagnosis of graft dysfunction facilitates clinical intervention of kidneys with salvageable function. New advances in magnetic resonance imaging (MRI) technology have enabled the calculation of various renal parameters that were previously not feasible to measure noninvasively. Diffusion-weighted imaging provides information on renal diffusion and perfusion simultaneously, with quantification by the apparent diffusion coefficient, the decrease of which reflects renal function impairment. Diffusion-tensor imaging accounts for the directionality of molecular motion and measures fractional anisotropy of the kidneys. Blood oxygen level-dependent MR evaluates intrarenal oxygen bioavailability, generating the parameter of R2* (reflecting the concentration of deoxyhemoglobin). A decrease in R2* could happen during acute rejection. MR nephro-urography/renography demonstrates structural data depicting urinary tract obstructions and functional data regarding the glomerular filtration and blood flow. MR angiography details the transplant vasculature and is particularly suitable for detecting vascular complications, with good correlation with digital subtraction angiography. Other functional MRI technologies, such as arterial spin labeling and MR spectroscopy, are showing additional promise. This review highlights MRI as a comprehensive modality to diagnose a variety of etiologies of graft dysfunction, including prerenal (e.g., renal vasculature), renal (intrinsic causes) and postrenal (e.g., obstruction of the collecting system) etiologies.
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Wypych-Klunder K, Adamowicz A, Lemanowicz A, Szczęsny W, Włodarczyk Z, Serafin Z. Diffusion-weighted MR imaging of transplanted kidneys: Preliminary report. Pol J Radiol 2014; 79:94-8. [PMID: 24826200 PMCID: PMC4018246 DOI: 10.12659/pjr.890502] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 02/17/2014] [Indexed: 12/27/2022] Open
Abstract
Background An aim of this study was to assess the feasibility of DWI in the early period after kidney transplantation. We also aimed to compare ADC and eADC values in the cortex and medulla of the kidney, to estimate image noise and variability of measurements, and to verify possible relation between selected labolatory results and diffusion parameters in the transplanted kidney. Material/Methods Examinations were performed using a 1.5 T MR unit. DWI (SE/EPI) was performed in the axial plane using b-values of 600 and 1000. ADC and eADC measurements were performed in four regions of interest within the renal cortex and in three regions within the medulla. Relative variability of results and signal-to-noise ratio (SNR) were calculated. Results The analysis included 15 patients (mean age 52 years). The mean variability of ADC was significantly lower than that of eADC (6.8% vs. 10.8%, respectively; p<0.0001). The mean variability of measurements performed in the cortex was significantly lower than that in the medulla (6.2% vs. 11.5%, respectively; p<0.005). The mean SNR was higher in the measurements using b600 than b1000, it was higher in ADC maps than in the eADC maps, and it was higher in the cortex than in the medulla. ADC and eADC measured at b1000 in the cortex were higher in the group of the patients with eGFR ≤30 ml/min./1.73 m2 as compared to patients with eGFR >30 ml/min./1.73 m2 (p<0.05). Conclusions Diffusion-weighted imaging of transplanted kidneys is technically challenging, especially in patients in the early period after transplantation. From a technical point of view, the best quality parameters offer quality ADC measurement in the renal cortex using b1000. ADC and eADC values in the renal cortex measured at b1000 present a relationship with eGFR.
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Affiliation(s)
- Katarzyna Wypych-Klunder
- Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Andrzej Adamowicz
- Department of General Surgery and Transplantology, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Adam Lemanowicz
- Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Wojciech Szczęsny
- Department of General Surgery and Transplantology, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Zbigniew Włodarczyk
- Department of General Surgery and Transplantology, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
| | - Zbigniew Serafin
- Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland
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Faubel S. Renal relevant radiology: introduction. Clin J Am Soc Nephrol 2014; 9:371-2. [PMID: 24510108 DOI: 10.2215/cjn.10211013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Sarah Faubel
- Division of Internal Medicine, Nephrology, University of Colorado and Denver Veterans Affairs Medical Center, Denver, Colorado
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