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Jeerararuensak W, Taweemonkongsap T, Larpparisuth N, Tantranont N, Chotikawanich E, Jitpraphai S, Woranisarakul V, Hansomwong T. Color Doppler Guided in Early Renal Allograft Biopsy: A Safer and Non-Inferior Technique. Transplant Proc 2023; 55:2385-2391. [PMID: 37872065 DOI: 10.1016/j.transproceed.2023.09.016] [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: 05/02/2023] [Revised: 08/07/2023] [Accepted: 09/22/2023] [Indexed: 10/25/2023]
Abstract
BACKGROUND This study compared a novel technique for renal allograft biopsy, color Doppler ultrasound-guided biopsy (CDUS-Bx), with routine ultrasound-guided biopsy (RUS-Bx). METHODS A retrospective review was conducted on 111 patients, with 42 undergoing CDUS-Bx and 69 undergoing RUS-Bx. Urologists used an 18-gauge automatic spring-loaded biopsy needle for all procedures. CDUS-Bx tissue collection was guided by identifying renal vessels with color Doppler mode. RESULTS Overall, the adequacy rate was 90.1%, with a higher number of glomeruli obtained in the CDUS-Bx group (25.6 ± 10.3 vs. 20.6 ± 11.3, P = .008). Acute tubular necrosis was the most frequent pathological diagnosis, with a higher prevalence in the CDUS-Bx group (69% vs 40.6%). T cell-mediated rejection had a lower incidence in the CDUS-Bx group (4.8% vs 21.7%), and antibody-mediated rejection was comparable between the 2 groups. The most common complication was microscopic hematuria, which was significantly less frequent in the CDUS-Bx group (48.7% vs 70.1%, P = .028), but there was no significant difference in the rate of gross hematuria between CDUS-Bx and RUS-Bx (11.9% vs 11.6%, P = .961). The number of cores was the only predictor of adequate biopsy, with a 93.2% adequacy rate after 3 cores of allograft biopsy. Multivariate analysis revealed that only the guiding type, CDUS-Bx, was associated with less microscopic hematuria (adjusted odds ratio 0.325, P = .018). CONCLUSIONS Color Doppler ultrasound-guided biopsy had comparable tissue adequacy to RUS-Bx, with a lower incidence of microscopic hematuria. These findings suggest that CDUS-Bx may be a safe and effective alternative to RUS-Bx for allograft biopsy.
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Affiliation(s)
- Wasin Jeerararuensak
- Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Tawatchai Taweemonkongsap
- Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Nuttasith Larpparisuth
- Division of Nephrology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Ngoentra Tantranont
- Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Ekkarin Chotikawanich
- Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Siros Jitpraphai
- Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Varat Woranisarakul
- Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Thitipat Hansomwong
- Division of Urology, Department of Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
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Jiménez-Coll V, El Kaaoui El Band J, Llorente S, González-López R, Fernández-González M, Martínez-Banaclocha H, Galián JA, Botella C, Moya-Quiles MR, Minguela A, Legaz I, Muro M. All That Glitters in cfDNA Analysis Is Not Gold or Its Utility Is Completely Established Due to Graft Damage: A Critical Review in the Field of Transplantation. Diagnostics (Basel) 2023; 13:1982. [PMID: 37370877 DOI: 10.3390/diagnostics13121982] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/24/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
In kidney transplantation, a biopsy is currently the gold standard for monitoring the transplanted organ. However, this is far from an ideal screening method given its invasive nature and the discomfort it can cause the patient. Large-scale studies in renal transplantation show that approximately 1% of biopsies generate major complications, with a risk of macroscopic hematuria greater than 3.5%. It would not be until 2011 that a method to detect donor-derived cell-free DNA (dd-cfDNA) employing digital PCR was devised based on analyzing the differences in SNPs between the donor and recipient. In addition, since the initial validation studies were carried out at the specific moments in which rejection was suspected, there is still not a good understanding of how dd-cfDNA levels naturally evolve post-transplant. In addition, various factors, both in the recipient and the donor, can influence dd-cfDNA levels and cause increases in the levels of dd-cfDNA themselves without suspicion of rejection. All that glitters in this technology is not gold; therefore, in this article, we discuss the current state of clinical studies, the benefits, and disadvantages.
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Affiliation(s)
- Victor Jiménez-Coll
- Immunology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
| | - Jaouad El Kaaoui El Band
- Immunology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
| | - Santiago Llorente
- Nephrology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
| | - Rosana González-López
- Immunology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
| | - Marina Fernández-González
- Immunology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
| | - Helios Martínez-Banaclocha
- Immunology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
| | - José Antonio Galián
- Immunology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
| | - Carmen Botella
- Immunology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
| | - María Rosa Moya-Quiles
- Immunology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
| | - Alfredo Minguela
- Immunology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
| | - Isabel Legaz
- Department of Legal and Forensic Medicine, Biomedical Research Institute of Murcia (IMIB), Faculty of Medicine, Regional Campus of International Excellence "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain
| | - Manuel Muro
- Immunology Service, University Clinical Hospital Virgen de la Arrixaca, Biomedical Research Institute of Murcia (IMIB), 30120 Murcia, Spain
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Das CJ, Kubihal V, Kumar S, Agarwal SK, Dinda AK, Sreenivas V. Assessment of renal allograft rejection with diffusion tensor imaging. Br J Radiol 2023; 96:20220722. [PMID: 36607279 PMCID: PMC9975367 DOI: 10.1259/bjr.20220722] [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: 07/23/2022] [Revised: 11/07/2022] [Accepted: 12/12/2022] [Indexed: 01/07/2023] Open
Abstract
OBJECTIVES To investigate the value of DTI in differentiation of renal allograft rejection from well-functioning stable allograft, using fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values. METHODS In this prospective study, 22 transplant recipients with well-functioning stable allograft (group A) and 20 patients with renal allograft rejection (group B + C) were recruited over a period of 19 months from January 2018 to July 2019. DTI-MRI was performed in all the patients, and FA and ADC values were measured in cortical and medullary regions of the transplanted kidney. On biopsy, graft rejection was classified as acute (group B) (n = 7) and chronic graft rejection (group C) (n = 13) based on the BANNF scoring system. Statistical analysis was performed using STATA v.14.0. RESULTS Statistically significant difference between group A and group B + C was noted for cortical (p < 0.001), and medullary (p = 0.003) FA values, and cortical (p = 0.020), and medullary (p = 0.046) ADC values. Cortical(p < 0.001) and Medullary(p = 0.020) FA values showed statistically significant difference between group A and group C, and cortical FA value(p = 0.012) also showed statistically significant difference between group B and group C. AUC (to differentiate between renal allograft rejection and well-functioning stable allograft) for cortical, and medullary FA values and cortical and medullary ADC values were 0.853(p < 0.001), 0.757(p = 0.004), 0.709(p = 0.021) and 0.736(p = 0.009), respectively. CONCLUSION AND ADVANCES IN KNOWLEDGE DTI is a promising functional MRI technique for the non-invasive assessment of renal allograft function. Diffusion parameters, such as FA and ADC values, can be useful in the differentiation of renal allograft rejection from well-functioning stable allograft.
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Affiliation(s)
- Chandan Jyoti Das
- Department of Radiodiagnosis and Interventional Radiology, All India Institute of Medical Sciences, New Delhi, India
| | - Vijay Kubihal
- Department of Radiodiagnosis and Interventional Radiology, All India Institute of Medical Sciences, New Delhi, India
| | - Sambuddha Kumar
- Department of Radiodiagnosis and Interventional Radiology, All India Institute of Medical Sciences, New Delhi, India
| | - Sanjay Kumar Agarwal
- Department of Nephrology, All India Institute of Medical Sciences, New Delhi, India
| | - Amit Kumar Dinda
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India
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Aslani N, Galehdar N, Garavand A. A systematic review of data mining applications in kidney transplantation. INFORMATICS IN MEDICINE UNLOCKED 2023. [DOI: 10.1016/j.imu.2023.101165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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5
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Coemans M, Verbeke G, Naesens M. A joint transition model for evaluating eGFR as biomarker for rejection after kidney transplantation. STAT MODEL 2021. [DOI: 10.1177/1471082x211048695] [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
The estimated glomerular filtration rate (eGFR) quantifies kidney graft function and is measured repeatedly after transplantation. Kidney graft rejection is diagnosed by performing biopsies on a regular basis (protocol biopsies at time of stable eGFR) or by performing biopsies due to clinical cause (indication biopsies at time of declining eGFR). The diagnostic value of the eGFR evolution as biomarker for rejection is not well established. To this end, we built a joint model which combines characteristics of transition models and shared parameter models to carry over information from one biopsy to the next, taking into account the longitudinal information of eGFR collected in between. From our model, applied to data of University Hospitals Leuven (870 transplantations, 2 635 biopsies), we conclude that a negative deviation from the mean eGFR slope increases the probability of rejection in indication biopsies, but that, on top of the biopsy history, there is little benefit in using the eGFR profile for diagnosing rejection. Methodologically, our model fills a gap in the biomarker literature by relating a frequently (repeatedly) measured continuous outcome with a less frequently (repeatedly) measured binary indicator. The developed joint transition model is flexible and applicable to multiple other research settings.
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Affiliation(s)
- Maarten Coemans
- L-Biostat, KU Leuven, Leuven, Belgium
- Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Geert Verbeke
- I-Biostat, Universiteit Hasselt & KU Leuven, Hasselt & Leuven, Belgium
| | - Maarten Naesens
- Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
- Department of Nephrology and Renal Transplantation, University Hospitals Leuven, Leuven, Belgium
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Shehata M, Ghazal M, Khalifeh HA, Khalil A, Shalaby A, Dwyer AC, Bakr AM, Keynton R, El-Baz A. A DEEP LEARNING-BASED CAD SYSTEM FOR RENAL ALLOGRAFT ASSESSMENT: DIFFUSION, BOLD, AND CLINICAL BIOMARKERS. PROCEEDINGS. INTERNATIONAL CONFERENCE ON IMAGE PROCESSING 2020; 2020:355-359. [PMID: 34720753 PMCID: PMC8553095 DOI: 10.1109/icip40778.2020.9190818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Recently, studies for non-invasive renal transplant evaluation have been explored to control allograft rejection. In this paper, a computer-aided diagnostic system has been developed to accommodate with an early-stage renal transplant status assessment, called RT-CAD. Our model of this system integrated multiple sources for a more accurate diagnosis: two image-based sources and two clinical-based sources. The image-based sources included apparent diffusion coefficients (ADCs) and the amount of deoxygenated hemoglobin (R2*). More specifically, these ADCs were extracted from 47 diffusion weighted magnetic resonance imaging (DW-MRI) scans at 11 different b-values (b0, b50, b100, …, b1000 s/mm2), while the R2* values were extracted from 30 blood oxygen level-dependent MRI (BOLD-MRI) scans at 5 different echo times (2ms, 7ms, 12ms, 17ms, and 22ms). The clinical sources included serum creatinine (SCr) and creatinine clearance (CrCl). First, the kidney was segmented through the RT-CAD system using a geometric deformable model called a level-set method. Second, both ADCs and R2* were estimated for common patients (N = 30) and then were integrated with the corresponding SCr and CrCl. Last, these integrated biomarkers were considered the discriminatory features to be used as trainers and testers for future deep learning-based classifiers such as stacked auto-encoders (SAEs). We used a k-fold cross-validation criteria to evaluate the RT-CAD system diagnostic performance, which achieved the following scores: 93.3%, 90.0%, and 95.0% in terms of accuracy, sensitivity, and specificity in differentiating between acute renal rejection (AR) and non-rejection (NR). The reliability and completeness of the RT-CAD system was further accepted by the area under the curve score of 0.92. The conclusions ensured that the presented RT-CAD system has a high reliability to diagnose the status of the renal transplant in a non-invasive way.
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Affiliation(s)
- Mohamed Shehata
- BioImaging Lab, Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - Mohammed Ghazal
- Faculty of Engineering, Abu Dhabi University, Abu Dhabi, UAE
| | | | - Ashraf Khalil
- Faculty of Engineering, Abu Dhabi University, Abu Dhabi, UAE
| | - Ahmed Shalaby
- BioImaging Lab, Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - Amy C Dwyer
- Pediatric Nephrology Unit, Mansoura University Children's Hospital, University of Mansoura, Egypt
| | - Ashraf M Bakr
- Kidney Disease Program, University of Louisville, Louisville, KY, USA
| | - Robert Keynton
- BioImaging Lab, Bioengineering Department, University of Louisville, Louisville, KY, USA
| | - Ayman El-Baz
- BioImaging Lab, Bioengineering Department, University of Louisville, Louisville, KY, USA
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7
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Abstract
Early detection of graft injury after kidney transplantation is key to maintaining long-term good graft function. Graft injury could be due to a multitude of factors including ischaemia reperfusion injury, cell or antibody-mediated rejection, progressive interstitial fibrosis and tubular atrophy, infections and toxicity from the immunosuppressive drugs themselves. The current gold standard for assessing renal graft dysfunction is renal biopsy. However, biopsy is usually late when triggered by a change in serum creatinine and of limited utility in diagnosis of early injury when histological changes are equivocal. Therefore, there is a need for timely, objective and non-invasive diagnostic techniques with good early predictive value to determine graft injury and provide precision in titrating immunosuppression. We review potential novel plasma and urine biomarkers that offer sensitive new strategies for early detection and provide major insights into mechanisms of graft injury. This is a rapidly expanding field, but it is likely that a combination of biomarkers will be required to provide adequate sensitivity and specificity for detecting graft injury.
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8
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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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Gordon CE, Tatsis V. Shearing-force injury of a kidney transplant graft during cesarean section: a case report and review of the literature. BMC Nephrol 2019; 20:94. [PMID: 30885165 PMCID: PMC6423748 DOI: 10.1186/s12882-019-1281-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 03/06/2019] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND With an increasing number of reproductive-aged women undergoing renal transplantation coupled with improved fertility post-transplantation, more women are becoming pregnant with a kidney transplant in place. This leads to increased risk of perinatal complications such as pre-eclampsia, gestational diabetes, preterm delivery and Cesarean section. Given that kidney transplants are often placed extra-peritoneally in the iliac fossa, there is also a risk of damage to the transplanted kidney at the time of Cesarean section. CASE PRESENTATION We present a case of shearing-force injury to a transplanted kidney at the time of repeat Cesarean section due to adherence of the organ to the overlying fascia. This is the first known case of an injury by this mechanism. CONCLUSION Pre-operative planning with organ mapping and incision planning is imperative, with consideration for a vertical midline incision to avoid direct or shearing forces on the transplant kidney. Preoperative collaboration with the Transplant Surgery team is also important so they are available in case of emergency or need for intraoperative consultation.
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Affiliation(s)
- Catherine E Gordon
- Department of Obstetrics & Gynecology, University of California, Irvine, 333 City Blvd, West - Suite 1400, Orange, CA, 92868, USA.
| | - Vasiliki Tatsis
- Department of Obstetrics & Gynecology, University of California, Irvine, 333 City Blvd, West - Suite 1400, Orange, CA, 92868, USA
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Sherif MF, Abu Alghar MI, Alshafe MH, Badra AG. Assessment of acute renal allograft dysfunction by MRI diffusion techniques. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2018. [DOI: 10.1016/j.ejrnm.2018.06.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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Shehata M, Mahmoud A, Soliman A, Khalifa F, Ghazal M, Abou El-Ghar M, El-Melegy M, El-Baz A. 3D kidney segmentation from abdominal diffusion MRI using an appearance-guided deformable boundary. PLoS One 2018; 13:e0200082. [PMID: 30005069 PMCID: PMC6044527 DOI: 10.1371/journal.pone.0200082] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 06/19/2018] [Indexed: 12/20/2022] Open
Abstract
A new technique for more accurate automatic segmentation of the kidney from its surrounding abdominal structures in diffusion-weighted magnetic resonance imaging (DW-MRI) is presented. This approach combines a new 3D probabilistic shape model of the kidney with a first-order appearance model and fourth-order spatial model of the diffusion-weighted signal intensity to guide the evolution of a 3D geometric deformable model. The probabilistic shape model was built from labeled training datasets to produce a spatially variant, independent random field of region labels. A Markov-Gibbs random field spatial model with up to fourth-order interactions was adequate to capture the inhomogeneity of renal tissues in the DW-MRI signal. A new analytical approach estimated the Gibbs potentials directly from the DW-MRI data to be segmented, in order that the segmentation procedure would be fully automatic. Finally, to better distinguish the kidney object from the surrounding tissues, marginal gray level distributions inside and outside of the deformable boundary were modeled with adaptive linear combinations of discrete Gaussians (first-order appearance model). The approach was tested on a cohort of 64 DW-MRI datasets with b-values ranging from 50 to 1000 s/mm2. The performance of the presented approach was evaluated using leave-one-subject-out cross validation and compared against three other well-known segmentation methods applied to the same DW-MRI data using the following evaluation metrics: 1) the Dice similarity coefficient (DSC); 2) the 95-percentile modified Hausdorff distance (MHD); and 3) the percentage kidney volume difference (PKVD). High performance of the new approach was confirmed by the high DSC (0.95±0.01), low MHD (3.9±0.76) mm, and low PKVD (9.5±2.2)% relative to manual segmentation by an MR expert (a board certified radiologist).
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Affiliation(s)
- Mohamed Shehata
- Bioengineering Department, University of Louisville, Louisville, KY, United States of America
| | - Ali Mahmoud
- Bioengineering Department, University of Louisville, Louisville, KY, United States of America
| | - Ahmed Soliman
- Bioengineering Department, University of Louisville, Louisville, KY, United States of America
| | - Fahmi Khalifa
- Department of Electronics and Communications Engineering, Mansoura University, Mansoura, Egypt
| | - Mohammed Ghazal
- Bioengineering Department, University of Louisville, Louisville, KY, United States of America
- Electrical and Computer Engineering Department, Abu Dhabi University, Abu Dhabi, UAE
| | - Mohamed Abou El-Ghar
- Radiology Department, Urology and Nephrology Center, University of Mansoura, Mansoura, Egypt
| | - Moumen El-Melegy
- Department of Electrical Engineering, Assiut University, Assiut, Egypt
| | - Ayman El-Baz
- Bioengineering Department, University of Louisville, Louisville, KY, United States of America
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Shehata M, Khalifa F, Soliman A, Ghazal M, Taher F, El-Ghar MA, Dwyer AC, Gimel'farb G, Keynton RS, El-Baz A. Computer-Aided Diagnostic System for Early Detection of Acute Renal Transplant Rejection Using Diffusion-Weighted MRI. IEEE Trans Biomed Eng 2018; 66:539-552. [PMID: 29993503 DOI: 10.1109/tbme.2018.2849987] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Early diagnosis of acute renal transplant rejection (ARTR) is critical for accurate treatment. Although the current gold standard, diagnostic technique is renal biopsy, it is not preferred due to its invasiveness, long recovery time (1-2 weeks), and potential for complications, e.g., bleeding and/or infection. METHODS This paper presents a computer-aided diagnostic (CAD) system for early ARTR detection using (3D + b-value) diffusion-weighted (DW) magnetic resonance imaging (MRI) data. The CAD process starts from kidney tissue segmentation with an evolving geometric (level-set-based) deformable model. The evolution is guided by a voxel-wise stochastic speed function, which follows from a joint kidney-background Markov-Gibbs random field model accounting for an adaptive kidney shape prior and on-going kidney-background visual appearances. A B-spline-based three-dimensional data alignment is employed to handle local deviations due to breathing and heart beating. Then, empirical cumulative distribution functions of apparent diffusion coefficients of the segmented DW-MRI at different b-values are collected as discriminatory transplant status features. Finally, a deep-learning-based classifier with stacked nonnegative constrained autoencoders is employed to distinguish between rejected and nonrejected renal transplants. RESULTS In our initial "leave-one-subject-out" experiment on 100 subjects, [Formula: see text] of the subjects were correctly classified. The subsequent four-fold and ten-fold cross-validations gave the average accuracy of [Formula: see text] and [Formula: see text], respectively. CONCLUSION These results demonstrate the promise of this new CAD system to reliably diagnose renal transplant rejection. SIGNIFICANCE The technology presented here can significantly impact the quality of care of renal transplant patients since it has the potential to replace the gold standard in kidney diagnosis, biopsy.
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Hollis E, Shehata M, Abou El-Ghar M, Ghazal M, El-Diasty T, Merchant M, Switala AE, El-Baz A. Statistical analysis of ADCs and clinical biomarkers in detecting acute renal transplant rejection. Br J Radiol 2017; 90:20170125. [PMID: 28937266 DOI: 10.1259/bjr.20170125] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE The main goal of this study is to determine which parameters [e.g. clinical biomarkers, demographics and image-markers using 4D (3D + b-value) diffusion-weighted MRI (DW-MRI)] are more correlated with transplanted kidney status in patients who have undergone kidney transplantation, and can be used for early assessment of acute renal rejection. METHODS The study included 16 patients with stable graft function and 37 patients with acute rejection (AR), determined by renal biopsy post-transplantation. 3D DW-MRI of each allograft had been acquired using a series of b-values 50 and 100-1000 in steps of 100 smm-2. The kidney was automatically segmented and co-aligned across series for motion correction using geometric deformable models. Volume-averaged apparent diffusion coefficients (ADCs) at each b-value were calculated. All possible subsets of ADC were used, along with patient age, sex, serum plasma creatinine (SPCr) and creatinine clearance (CrCl), as predictors in 211 logistic regression models where AR was the outcome variable. Predictive value of ADC at each b-value was assessed using its Akaike weight. RESULTS ANOVA of the saturated model found that odds of AR depended significantly on SPCr, CrCl and ADC at b = 500, 600, 700 and 900 smm-2. The model incorporating ADC at b = 100 and700 smm-2 had the lowest value of the Akaike information criterion; the same two b-values also had the greatest Akaike weights. For comparison, the top 10 submodels and the full model were reported. CONCLUSION Preliminary findings suggest that ADC provides improved detection of AR than lab values alone. At least two non-zero gradient strengths should be used for optimal results. Advances in knowledge: This paper investigated possible correlations between image-based and clinical biomarkers, and the fusion of both with respect to biopsy diagnosis of AR.
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Affiliation(s)
- Elizabeth Hollis
- 1 Department of Bioengineering,BioImaging Laboratory, University of Louisville , Louisville, KY , USA.,2 Department of Pharmacology and Toxicology, University of Louisville , Louisville, KY , USA
| | - Mohamed Shehata
- 1 Department of Bioengineering,BioImaging Laboratory, University of Louisville , Louisville, KY , USA
| | - Mohamed Abou El-Ghar
- 3 Department of Radiology,Urology and Nephrology Center, University of Mansoura , Mansoura , Egypt
| | - Mohammed Ghazal
- 1 Department of Bioengineering,BioImaging Laboratory, University of Louisville , Louisville, KY , USA.,4 Department of Electrical and Computer Engineering, Abu Dhabi University , Abu Dhabi , UAE
| | - Tarek El-Diasty
- 3 Department of Radiology,Urology and Nephrology Center, University of Mansoura , Mansoura , Egypt
| | - Michael Merchant
- 2 Department of Pharmacology and Toxicology, University of Louisville , Louisville, KY , USA
| | - Andrew E Switala
- 1 Department of Bioengineering,BioImaging Laboratory, University of Louisville , Louisville, KY , USA
| | - Ayman El-Baz
- 1 Department of Bioengineering,BioImaging Laboratory, University of Louisville , Louisville, KY , USA
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