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Rabindranath M, Zaya R, Prayitno K, Orchanian-Cheff A, Patel K, Jaeckel E, Bhat M. A Comprehensive Review of Liver Allograft Fibrosis and Steatosis: From Cause to Diagnosis. Transplant Direct 2023; 9:e1547. [PMID: 37854023 PMCID: PMC10581596 DOI: 10.1097/txd.0000000000001547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/11/2023] [Accepted: 09/14/2023] [Indexed: 10/20/2023] Open
Abstract
Despite advances in posttransplant care, long-term outcomes for liver transplant recipients remain unchanged. Approximately 25% of recipients will advance to graft cirrhosis and require retransplantation. Graft fibrosis progresses in the context of de novo or recurrent disease. Recurrent hepatitis C virus infection was previously the most important cause of graft failure but is now curable in the majority of patients. However, with an increasing prevalence of obesity and diabetes and nonalcoholic fatty liver disease as the most rapidly increasing indication for liver transplantation, metabolic dysfunction-associated liver injury is anticipated to become an important cause of graft fibrosis alongside alloimmune hepatitis and alcoholic liver disease. To better understand the landscape of the graft fibrosis literature, we summarize the associated epidemiology, cause, potential mechanisms, diagnosis, and complications. We additionally highlight the need for better noninvasive methods to ameliorate the management of graft fibrosis. Some examples include leveraging the microbiome, genetic, and machine learning methods to address these limitations. Overall, graft fibrosis is routinely seen by transplant clinicians, but it requires a better understanding of its underlying biology and contributors that can help inform diagnostic and therapeutic practices.
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Affiliation(s)
- Madhumitha Rabindranath
- Ajmera Transplant Program, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
| | - Rita Zaya
- Ajmera Transplant Program, University Health Network, Toronto, ON, Canada
| | - Khairunnadiya Prayitno
- Ajmera Transplant Program, University Health Network, Toronto, ON, Canada
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
| | - Ani Orchanian-Cheff
- Library and Information Services, University Health Network, Toronto, ON, Canada
| | - Keyur Patel
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Elmar Jaeckel
- Ajmera Transplant Program, University Health Network, Toronto, ON, Canada
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Mamatha Bhat
- Ajmera Transplant Program, University Health Network, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
- Division of Gastroenterology and Hepatology, Department of Medicine, University of Toronto, Toronto, ON, Canada
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2
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Ozturk A, Olson MC, Samir AE, Venkatesh SK. Liver fibrosis assessment: MR and US elastography. Abdom Radiol (NY) 2022; 47:3037-3050. [PMID: 34687329 PMCID: PMC9033887 DOI: 10.1007/s00261-021-03269-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 08/31/2021] [Accepted: 09/01/2021] [Indexed: 01/18/2023]
Abstract
Elastography has emerged as a preferred non-invasive imaging technique for the clinical assessment of liver fibrosis. Elastography methods provide liver stiffness measurement (LSM) as a surrogate quantitative biomarker for fibrosis burden in chronic liver disease (CLD). Elastography can be performed either with ultrasound or MRI. Currently available ultrasound-based methods include strain elastography, two-dimensional shear wave elastography (2D-SWE), point shear wave elastography (pSWE), and vibration-controlled transient elastography (VCTE). MR Elastography (MRE) is widely available as two-dimensional gradient echo MRE (2D-GRE-MRE) technique. US-based methods provide estimated Young's modulus (eYM) and MRE provides magnitude of the complex shear modulus. MRE and ultrasound methods have proven to be accurate methods for detection of advanced liver fibrosis and cirrhosis. Other clinical applications of elastography include liver decompensation prediction, and differentiation of non-alcoholic steatohepatitis (NASH) from simple steatosis (SS). In this review, we briefly describe the different elastography methods, discuss current clinical applications, and provide an overview of advances in the field of liver elastography.
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Affiliation(s)
- Arinc Ozturk
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Michael C Olson
- Division of Abdominal Imaging, Radiology, Mayo Clinic Rochester, 200, First Street SW, Rochester, MN, 55905, USA
| | - Anthony E Samir
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Sudhakar K Venkatesh
- Division of Abdominal Imaging, Radiology, Mayo Clinic Rochester, 200, First Street SW, Rochester, MN, 55905, USA.
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3
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Han MAT, Olivo R, Choi CJ, Pyrsopoulos N. De novo and recurrence of metabolic dysfunction-associated fatty liver disease after liver transplantation. World J Hepatol 2021; 13:1991-2004. [PMID: 35070003 PMCID: PMC8727208 DOI: 10.4254/wjh.v13.i12.1991] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 07/27/2021] [Accepted: 11/25/2021] [Indexed: 02/06/2023] Open
Abstract
Metabolic dysfunction-associated fatty liver disease (MAFLD) is a new acronym adopted from the consensus of international experts. Given the increasing prevalence of MAFLD in pre-transplant settings, de novo and recurrent graft steatosis/MAFLD are common in post-transplant settings. The impact of graft steatosis on long-term outcomes is unclear. The current knowledge of incidence rate, risk factors, diagnosis, long-term outcomes, and management of graft steatosis (both de novo and recurrent) is discussed in this review.
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Affiliation(s)
- Ma Ai Thanda Han
- Department of Gastroenterology and Hepatology, Rutgers New Jersey Medical School, Newark, NJ 07103, United States
| | - Raquel Olivo
- Department of Gastroenterology and Hepatology, Rutgers University, New Jersey Medical School, Newark, NJ 07103, United States
| | - Catherine J Choi
- Department of Medicine, Rutgers New Jersey Medical School, Newark, NJ 07101, United States
| | - Nikolaos Pyrsopoulos
- Department of Gastroenterology and Hepatology, Rutgers New Jersey Medical School, Newark, NJ 07103, United States
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4
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Navin PJ, Olson MC, Knudsen JM, Venkatesh SK. Elastography in the evaluation of liver allograft. Abdom Radiol (NY) 2021; 46:96-110. [PMID: 31950204 DOI: 10.1007/s00261-019-02400-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Elastography is an established technique in the evaluation of chronic liver diseases. While there is a large clinical experience and data available regarding the performance of elastography in native liver, elastography experience with liver grafts is limited and still growing. Both ultrasound-based elastography techniques and MR Elastography (MRE) are useful in the assessment of liver fibrosis in liver transplants. Technical modifications for performing elastography will be required for optimum evaluation of the graft. In general, caution needs to be exercised regarding the use of elastography immediately following transplantation as post-operative changes, perioperative conditions/complications, inflammation, and rejection can cause increased stiffness in the graft. In the follow-up, detection of increased stiffness with elastography is useful for predicting development of fibrosis in the graft. Adjunctive MRI or ultrasound with Doppler also provides comprehensive evaluation of anatomy, vascular anastomosis and patency, biliary tree, and stiffness for fibrosis. In this review, we provide a brief overview of elastography techniques available followed by the literature review of elastography in the evaluation of grafts and illustration with clinical examples.
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5
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MR elastography of liver: current status and future perspectives. Abdom Radiol (NY) 2020; 45:3444-3462. [PMID: 32705312 DOI: 10.1007/s00261-020-02656-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 07/06/2020] [Accepted: 07/09/2020] [Indexed: 02/08/2023]
Abstract
Non-invasive evaluation of liver fibrosis has evolved over the last couple of decades. Currently, elastography techniques are the most widely used non-invasive methods for clinical evaluation of chronic liver disease (CLD). MR elastography (MRE) of the liver has been used in the clinical practice for nearly a decade and continues to be widely accepted for detection and staging of liver fibrosis. With MRE, one can directly visualize propagating shear waves through the liver and an inversion algorithm in the scanner automatically converts the shear wave properties into an elastogram (stiffness map) on which liver stiffness can be calculated. The commonly used MRE method, two-dimensional gradient recalled echo (2D-GRE) sequence has produced excellent results in the evaluation of liver fibrosis in CLD from various etiologies and newer clinical indications continue to emerge. Advances in MRE technique, including 3D MRE, automated liver elasticity calculation, improvements in shear wave delivery and patient experience, are promising to provide a faster and more reliable MRE of liver. Innovations, including evaluation of mechanical parameters, such as loss modulus, displacement, and volumetric strain, are promising for comprehensive evaluation of CLD as well as understanding pathophysiology, and in differentiating various etiologies of CLD. In this review, the current status of the MRE of liver in CLD are outlined and followed by a brief description of advanced techniques and innovations in MRE of liver.
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6
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Taneja S, Roy A. Nonalcoholic steatohepatitis recurrence after liver transplant. Transl Gastroenterol Hepatol 2020; 5:24. [PMID: 32258528 DOI: 10.21037/tgh.2019.10.12] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 10/15/2019] [Indexed: 12/20/2022] Open
Abstract
Nonalcoholic steatohepatitis (NASH) is the fastest growing indication for liver transplant (LT)worldwide and is deemed to be the foremost indication in the near future. Recurrence of NASH can occur post LT and has been observed to be a common phenomenon. Baseline metabolic co-morbidities and worsening of metabolic profile post LT are the principal drivers of NASH recurrence. Liver biopsy remains the gold standard for establishing the diagnosis. However, noninvasive methods including transient elastography (TE) and magnetic resonance imaging (MRI) seem to be promising. The implications of recurrent NASH on post LT outcomes, graft steatosis, progression to fibrosis, overall survival, and cardiovascular associations warrant careful evaluation. Control of metabolic parameters and weight gain along with tailored immunosuppression remain the cornerstone of management. Extrapolation of the ever-increasing armamentarium of NASH pharmacotherapy specifically in this population of recurrent NAFLD remains a challenge for the future.
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Affiliation(s)
- Sunil Taneja
- Department of Hepatology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Akash Roy
- Department of Hepatology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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7
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Rezvani Habibabadi R, Khoshpouri P, Ghadimi M, Shaghaghi M, Ameli S, Hazhirkarzar B, Pandey P, Aliyari Ghasabeh M, Pandey A, Kamel IR. Comparison between ROI-based and volumetric measurements in quantifying heterogeneity of liver stiffness using MR elastography. Eur Radiol 2019; 30:1609-1615. [DOI: 10.1007/s00330-019-06478-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 09/01/2019] [Accepted: 09/27/2019] [Indexed: 12/15/2022]
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8
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El-Meteini M, Sakr M, Eldorry A, Mohran Z, Abdelkader NA, Dabbous H, Montasser I, Refaie R, Salah M, Aly M. Non-Invasive Assessment of Graft Fibrosis After Living Donor Liver Transplantation: Is There Still a Role for Liver Biopsy? Transplant Proc 2019; 51:2451-2456. [PMID: 31358454 DOI: 10.1016/j.transproceed.2019.01.197] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 01/03/2019] [Indexed: 12/13/2022]
Abstract
Non-invasive methods have evolved as a surrogate for liver biopsy such as indirect markers (aspartate transaminase to platelet ratio index, fibro-α score), transient elastography (TE), and magnetic resonance elastography (MRE). The aim of this study is to prospectively compare the value of MRE, TE, and indirect markers in detecting and staging allograft fibrosis compared to liver biopsies in patients who have undergone living donor liver transplantation for complications related to hepatitis C virus. A total of 31 living donor liver transplantation recipients with hepatitis C virus recurrence underwent a liver biopsy, TE, and MRE within 3 months of a liver biopsy. Fibrosis was assessed according to the biopsy and staged according to Metavir criteria. There was a significant correlation between both MRE and fibro-α scores, as well as histologic classification by liver biopsy (P = .02, .002). The diagnostic accuracy of MRE and fibro-α scores in diagnosing significant fibrosis (F ≥ 3) was measured as the area under the curve (.708 and .833, respectively). Both methods showed good diagnostic performance. TE and aspartate transaminase to platelet ratio index were insignificantly correlated with the degree of fibrosis in liver biopsy (P value of .134, .535). At a cutoff value of 5.5 kPa, MRE predicted graft fibrosis (Metavir stage ≥ 3) with 71.43% sensitivity, 75% specificity, 45.5% positive predictive value, and 90% negative predictive value; at a cutoff value > 1.47, fibro-α scores predicted significant graft fibrosis (Metavir stage ≥ 3) with 85.7% sensitivity and 70.83% specificity, with a positive predictive value of 46.2% and a negative predictive value of 94.4%. These data suggest that non-invasive methods could be considered a reliable tool in assessing significant graft fibrosis post-living donor liver transplantation.
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Affiliation(s)
- M El-Meteini
- Department of Hepatobiliary Surgery & Liver Transplantation, Ain Shams Center for Organ Transplantation (ASCOT), Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - M Sakr
- Tropical Medicine Department, Ain Shams Center for Organ Transplantation (ASCOT), Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - A Eldorry
- Interventional Radiology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Z Mohran
- Tropical Medicine Department, Ain Shams Center for Organ Transplantation (ASCOT), Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - N A Abdelkader
- Tropical Medicine Department, Ain Shams Center for Organ Transplantation (ASCOT), Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - H Dabbous
- Tropical Medicine Department, Ain Shams Center for Organ Transplantation (ASCOT), Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - I Montasser
- Tropical Medicine Department, Ain Shams Center for Organ Transplantation (ASCOT), Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - R Refaie
- Internal Medicine Department, Faculty of Medicine, Helwan University, Cairo, Egypt
| | - M Salah
- Tropical Medicine Department, Ain Shams Center for Organ Transplantation (ASCOT), Faculty of Medicine, Ain Shams University, Cairo, Egypt.
| | - M Aly
- Tropical Medicine Department, Ain Shams Center for Organ Transplantation (ASCOT), Faculty of Medicine, Ain Shams University, Cairo, Egypt
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9
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Germani G, Laryea M, Rubbia-Brandt L, Egawa H, Burra P, OʼGrady J, Watt KD. Management of Recurrent and De Novo NAFLD/NASH After Liver Transplantation. Transplantation 2019; 103:57-67. [PMID: 30335694 DOI: 10.1097/tp.0000000000002485] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nonalcoholic steatohepatitis (NASH) is a growing indication for liver transplant whether the primary or secondary cause of liver disease, and it is expected to be the leading indication in the years to come. Nonalcoholic steatohepatitis recurs after transplant but the impact of the recurrence on allograft and patient outcomes is unclear. A group of multidisciplinary transplant practice providers convened at the International Liver Transplantation Society NASH consensus conference with the purpose of determining the current knowledge and future directions for understanding the recurrence rates, risk and management of NASH in the transplant allograft. Specific questions relating to posttransplant NASH were proposed and reviewed in detail with recommendations on future actions to fill the knowledge gaps.
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Affiliation(s)
- Giacomo Germani
- Multivisceral Transplant Unit, Department of Surgery, Oncology and Gastroenterology, Padua University Hospital, Padua, Italy
| | - Marie Laryea
- University of Rochester Medical Center, Rochester NY
| | | | - Hiroto Egawa
- Department of Surgery, Institute of Gastroenterology, Tokyo Women's Medical University, Tokyo, Japan
| | - Patrizia Burra
- Multivisceral Transplant Unit, Department of Surgery, Oncology and Gastroenterology, Padua University Hospital, Padua, Italy
| | - John OʼGrady
- Institute of Liver Studies, King's College Hospital, London, United Kingdom
| | - Kymberly D Watt
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN
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Akkaya HE, Erden A, Kuru Öz D, Ünal S, Erden İ. Magnetic resonance elastography: basic principles, technique, and clinical applications in the liver. ACTA ACUST UNITED AC 2019; 24:328-335. [PMID: 30272563 DOI: 10.5152/dir.2018.18186] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Magnetic resonance elastography (MRE) is a constantly advancing technique for assessment of stiffness of tissues with newer technology and sequences. It is being increasingly used for the assessment of liver fibrosis. In this article, we discuss the advantages of MRE over biopsy and noninvasive methods such as US elastography in the assessment of liver fibrosis. Image acquisition and interpretation of liver MRE is also discussed.
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Affiliation(s)
| | - Ayşe Erden
- Department of Radiology, Ankara University School of Medicine, Ankara, Turkey
| | - Diğdem Kuru Öz
- Department of Radiology, Ankara University School of Medicine, Ankara, Turkey
| | - Sena Ünal
- Department of Radiology, Erzurum Local Training and Research Hospital, Erzurum, Turkey
| | - İlhan Erden
- Department of Radiology, Ankara University School of Medicine, Ankara, Turkey
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11
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Garteiser P, Doblas S, Van Beers BE. Magnetic resonance elastography of liver and spleen: Methods and applications. NMR IN BIOMEDICINE 2018; 31:e3891. [PMID: 29369503 DOI: 10.1002/nbm.3891] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 11/16/2017] [Accepted: 12/04/2017] [Indexed: 05/06/2023]
Abstract
The viscoelastic properties of the liver and spleen can be assessed with magnetic resonance elastography (MRE). Several actuators, MRI acquisition sequences and reconstruction algorithms have been proposed for this purpose. Reproducible results are obtained, especially when the examination is performed in standard conditions with the patient fasting. Accurate staging of liver fibrosis can be obtained by measuring liver stiffness or elasticity with MRE. Moreover, emerging evidence shows that assessing the tissue viscous parameters with MRE is useful for characterizing liver inflammation, non-alcoholic steatohepatitis, hepatic congestion, portal hypertension, and hepatic tumors. Further advances such as multifrequency acquisitions and compression-sensitive MRE may provide novel quantitative markers of hepatic and splenic mechanical properties that may improve the diagnosis of hepatic and splenic diseases.
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Affiliation(s)
- Philippe Garteiser
- Laboratory of Imaging Biomarkers, Center of Research on Inflammation, UMR 1149 INSERM-University Paris Diderot, Paris, France
| | - Sabrina Doblas
- Laboratory of Imaging Biomarkers, Center of Research on Inflammation, UMR 1149 INSERM-University Paris Diderot, Paris, France
| | - Bernard E Van Beers
- Laboratory of Imaging Biomarkers, Center of Research on Inflammation, UMR 1149 INSERM-University Paris Diderot, Paris, France
- Department of Radiology, Beaujon University Hospital Paris Nord, Clichy, France
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12
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Abstract
PURPOSE OF REVIEW The purpose of this review is to discuss the current imaging techniques for non-invasive assessment of liver fibrosis (LF). RECENT FINDINGS Elastography-based techniques are the most widely used imaging methods for the evaluation of LF. Currently, MR elastography (MRE) is the most accurate non-invasive method for detection and staging of LF. Ultrasound-based vibration-controlled transient elastography (VCTE) is the most widely used as it can be easily performed at the point of care but has technical limitations especially in the obese. Innovations and technical improvements continue to evolve in elastography for improving accuracy and avoiding misinterpretation from confounding factors. Other imaging methods including diffusion-weighted imaging (DWI), hepatocellular contrast-enhanced (HCE) MRI, T1 relaxometry, T1ρ imaging, textural analysis, liver surface nodularity, susceptibility-weighted imaging, and perfusion imaging are promising but need further evaluation and clinical validation. MRE is the most accurate imaging technique for assessment of LF.
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Affiliation(s)
- Rishi Philip Mathew
- Department of Radiology, Mayo Clinic, Mayo Clinic College of Medicine, 200, First Street SW, Rochester, MN, 55905, USA
| | - Sudhakar Kundapur Venkatesh
- Department of Radiology, Mayo Clinic, Mayo Clinic College of Medicine, 200, First Street SW, Rochester, MN, 55905, USA.
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13
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Kennedy P, Wagner M, Castéra L, Hong CW, Johnson CL, Sirlin CB, Taouli B. Quantitative Elastography Methods in Liver Disease: Current Evidence and Future Directions. Radiology 2018; 286:738-763. [PMID: 29461949 DOI: 10.1148/radiol.2018170601] [Citation(s) in RCA: 185] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chronic liver diseases often result in the development of liver fibrosis and ultimately, cirrhosis. Treatment strategies and prognosis differ greatly depending on the severity of liver fibrosis, thus liver fibrosis staging is clinically relevant. Traditionally, liver biopsy has been the method of choice for fibrosis evaluation. Because of liver biopsy limitations, noninvasive methods have become a key research interest in the field. Elastography enables the noninvasive measurement of tissue mechanical properties through observation of shear-wave propagation in the tissue of interest. Increasing fibrosis stage is associated with increased liver stiffness, providing a discriminatory feature that can be exploited by elastographic methods. Ultrasonographic (US) and magnetic resonance (MR) imaging elastographic methods are commercially available, each with their respective strengths and limitations. Here, the authors review the technical basis, acquisition techniques, and results and limitations of US- and MR-based elastography techniques. Diagnostic performance in the most common etiologies of chronic liver disease will be presented. Reliability, reproducibility, failure rate, and emerging advances will be discussed. © RSNA, 2018 Online supplemental material is available for this article.
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Affiliation(s)
- Paul Kennedy
- From the Translational and Molecular Imaging Institute (P.K., B.T.) and Department of Radiology (B.T.), Icahn School of Medicine at Mount Sinai, 1470 Madison Ave, New York, NY 10029; Department of Radiology, Sorbonne Universités, UPMC, Hôpital Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France (M.W.); Department of Hepatology, University Paris-VII, Hôpital Beaujon, Clichy, France (L.C.); Liver Imaging Group, Department of Radiology, University of California-San Diego, San Diego, Calif (C.W.H., C.B.S.); Department of Biomedical Engineering, University of Delaware, Newark, Del (C.L.J.)
| | - Mathilde Wagner
- From the Translational and Molecular Imaging Institute (P.K., B.T.) and Department of Radiology (B.T.), Icahn School of Medicine at Mount Sinai, 1470 Madison Ave, New York, NY 10029; Department of Radiology, Sorbonne Universités, UPMC, Hôpital Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France (M.W.); Department of Hepatology, University Paris-VII, Hôpital Beaujon, Clichy, France (L.C.); Liver Imaging Group, Department of Radiology, University of California-San Diego, San Diego, Calif (C.W.H., C.B.S.); Department of Biomedical Engineering, University of Delaware, Newark, Del (C.L.J.)
| | - Laurent Castéra
- From the Translational and Molecular Imaging Institute (P.K., B.T.) and Department of Radiology (B.T.), Icahn School of Medicine at Mount Sinai, 1470 Madison Ave, New York, NY 10029; Department of Radiology, Sorbonne Universités, UPMC, Hôpital Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France (M.W.); Department of Hepatology, University Paris-VII, Hôpital Beaujon, Clichy, France (L.C.); Liver Imaging Group, Department of Radiology, University of California-San Diego, San Diego, Calif (C.W.H., C.B.S.); Department of Biomedical Engineering, University of Delaware, Newark, Del (C.L.J.)
| | - Cheng William Hong
- From the Translational and Molecular Imaging Institute (P.K., B.T.) and Department of Radiology (B.T.), Icahn School of Medicine at Mount Sinai, 1470 Madison Ave, New York, NY 10029; Department of Radiology, Sorbonne Universités, UPMC, Hôpital Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France (M.W.); Department of Hepatology, University Paris-VII, Hôpital Beaujon, Clichy, France (L.C.); Liver Imaging Group, Department of Radiology, University of California-San Diego, San Diego, Calif (C.W.H., C.B.S.); Department of Biomedical Engineering, University of Delaware, Newark, Del (C.L.J.)
| | - Curtis L Johnson
- From the Translational and Molecular Imaging Institute (P.K., B.T.) and Department of Radiology (B.T.), Icahn School of Medicine at Mount Sinai, 1470 Madison Ave, New York, NY 10029; Department of Radiology, Sorbonne Universités, UPMC, Hôpital Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France (M.W.); Department of Hepatology, University Paris-VII, Hôpital Beaujon, Clichy, France (L.C.); Liver Imaging Group, Department of Radiology, University of California-San Diego, San Diego, Calif (C.W.H., C.B.S.); Department of Biomedical Engineering, University of Delaware, Newark, Del (C.L.J.)
| | - Claude B Sirlin
- From the Translational and Molecular Imaging Institute (P.K., B.T.) and Department of Radiology (B.T.), Icahn School of Medicine at Mount Sinai, 1470 Madison Ave, New York, NY 10029; Department of Radiology, Sorbonne Universités, UPMC, Hôpital Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France (M.W.); Department of Hepatology, University Paris-VII, Hôpital Beaujon, Clichy, France (L.C.); Liver Imaging Group, Department of Radiology, University of California-San Diego, San Diego, Calif (C.W.H., C.B.S.); Department of Biomedical Engineering, University of Delaware, Newark, Del (C.L.J.)
| | - Bachir Taouli
- From the Translational and Molecular Imaging Institute (P.K., B.T.) and Department of Radiology (B.T.), Icahn School of Medicine at Mount Sinai, 1470 Madison Ave, New York, NY 10029; Department of Radiology, Sorbonne Universités, UPMC, Hôpital Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France (M.W.); Department of Hepatology, University Paris-VII, Hôpital Beaujon, Clichy, France (L.C.); Liver Imaging Group, Department of Radiology, University of California-San Diego, San Diego, Calif (C.W.H., C.B.S.); Department of Biomedical Engineering, University of Delaware, Newark, Del (C.L.J.)
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14
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Imai H, Kamei H, Onishi Y, Ishizu Y, Ishigami M, Goto H, Ogura Y. Diagnostic Usefulness of APRI and FIB-4 for the Prediction of Liver Fibrosis After Liver Transplantation in Patients Infected with Hepatitis C Virus. Transplant Proc 2018; 50:1431-1436. [PMID: 29705278 DOI: 10.1016/j.transproceed.2018.03.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 03/01/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Aspartate transaminase-to-platelet ratio index (APRI) and fibrosis-4 (FIB-4) are well known as representative indirect serum biomarkers related to liver fibrosis. The usefulness of these markers for the diagnosis of liver fibrosis after liver transplantation (LT) in hepatitis C virus (HCV)-infected patients and the influence of splenectomy were investigated. METHODS From June 2003 to May 2014, 31 HCV-infected patients who underwent LT and postoperative follow-up liver biopsies were included in this study. The association between liver fibrosis and serum biomarkers and the influence of splenectomy on APRI and FIB-4 were also investigated. RESULTS A total of 195 biopsy specimens were collected, and liver fibrosis was identified as: F0, 59.7%; F1, 34.1%; and F2, 6.3%. Both APRI and FIB-4 were significantly higher in patients who showed F1 and F2 in liver biopsy specimen than F0 (P values, .009 and .022, respectively); sensitivity and specificity of APRI were, respectively, 63.4% and 66.7%, and those of FIB-4 were 57.7% and 69.6%. In 11 patients (35.5%) who underwent splenectomy at the time of LT, the cutoff values for APRI and FIB-4 were 0.61 and 1.41, which were significantly lower than the corresponding values (1.00 and 3.64) of patients without splenectomy. CONCLUSIONS APRI and FIB-4 could effectively estimate liver fibrosis after LT for HCV-related liver disease. For LT patients with splenectomy, APRI and FIB-4 were also useful to estimate liver fibrosis, but the standard values should be adjusted lower than those for patients without splenectomy.
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Affiliation(s)
- H Imai
- Department of Transplantation Surgery, Nagoya University School of Medicine, Nagoya, Japan
| | - H Kamei
- Department of Transplantation Surgery, Nagoya University School of Medicine, Nagoya, Japan
| | - Y Onishi
- Department of Transplantation Surgery, Nagoya University School of Medicine, Nagoya, Japan
| | - Y Ishizu
- Department of Gastroenterology and Hepatology, Nagoya University School of Medicine, Nagoya, Japan
| | - M Ishigami
- Department of Gastroenterology and Hepatology, Nagoya University School of Medicine, Nagoya, Japan
| | - H Goto
- Department of Gastroenterology and Hepatology, Nagoya University School of Medicine, Nagoya, Japan
| | - Y Ogura
- Department of Transplantation Surgery, Nagoya University School of Medicine, Nagoya, Japan.
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15
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Tan CH, Venkatesh SK. Magnetic Resonance Elastography and Other Magnetic Resonance Imaging Techniques in Chronic Liver Disease: Current Status and Future Directions. Gut Liver 2017; 10:672-86. [PMID: 27563019 PMCID: PMC5003189 DOI: 10.5009/gnl15492] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 11/29/2015] [Accepted: 12/15/2015] [Indexed: 12/13/2022] Open
Abstract
Recent advances in the noninvasive imaging of chronic liver disease have led to improvements in diagnosis, particularly with magnetic resonance imaging (MRI). A comprehensive evaluation of the liver may be performed with the quantification of the degree of hepatic steatosis, liver iron concentration, and liver fibrosis. In addition, MRI of the liver may be used to identify complications of cirrhosis, including portal hypertension, ascites, and the development of hepatocellular carcinoma. In this review article, we discuss the state of the art techniques in liver MRI, namely, magnetic resonance elastography, hepatobiliary phase MRI, and liver fat and iron quantification MRI. The use of these advanced techniques in the management of chronic liver diseases, including non-alcoholic fatty liver disease, will be elaborated.
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Affiliation(s)
- Cher Heng Tan
- Department of Diagnostic Radiology, Tan Tock Seng Hospital, Singapore
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16
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Han MAT, Saouaf R, Ayoub W, Todo T, Mena E, Noureddin M. Magnetic resonance imaging and transient elastography in the management of Nonalcoholic Fatty Liver Disease (NAFLD). Expert Rev Clin Pharmacol 2017; 10:379-390. [PMID: 28277807 DOI: 10.1080/17512433.2017.1299573] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
INTRODUCTION Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease and cirrhosis worldwide and the second most common cause of liver transplantation in major medical centers. Because liver steatosis and fibrosis severity are related to disease morbidity and mortality, the extent of disease, and disease progression, they need to be assessed and monitored. In addition, innovation with new drug developments requires disease staging and monitoring in both phase 2 and 3 clinical trials. Currently, disease assessment in both clinical practice and research is mostly performed by liver biopsy, an invasive, procedure with risks. Noninvasive, highly accurate tests are needed that could be used in clinical trials as surrogate endpoints and in clinical practice for monitoring patients. Area Covered: We discuss noninvasive tests, transient elastography (TE) with controlled attenuation parameter (CAP), magnetic resonance imaging (MRI), and MR elastography (MRE), summarize the available evidence of their usefulness for assessing steatosis and fibrosis. Therefore they could be used as clinical trials outcomes and in disease monitoring in clinical practice. Expert Commentary: TE with CAP, MRI and MRE are highly accurate noninvasive diagnostic tools for quantifying hepatic steatosis and fibrosis. Therefore they could be used as clinical trials outcomes and in disease monitoring in clinical practice.
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Affiliation(s)
- Ma Ai Thanda Han
- a Division of Digestive and Liver Diseases , Cedars-Sinai Medical Center , Los Angeles , California , USA
| | - Rola Saouaf
- b Department of Radiology , Cedars-Sinai Medical Center , Los Angeles , California , USA
| | - Walid Ayoub
- c Fatty Liver Program, Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center , Los Angeles , California , USA.,d Comprehensive Transplant Center, Cedars-Sinai Medical Center , Los Angeles , California , USA
| | - Tsuyoshi Todo
- d Comprehensive Transplant Center, Cedars-Sinai Medical Center , Los Angeles , California , USA
| | - Edward Mena
- e California Liver Research Institute , Pasadena , California , USA
| | - Mazen Noureddin
- c Fatty Liver Program, Division of Digestive and Liver Diseases, Cedars-Sinai Medical Center , Los Angeles , California , USA.,d Comprehensive Transplant Center, Cedars-Sinai Medical Center , Los Angeles , California , USA
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17
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Karanjia RN, Crossey MME, Cox IJ, Fye HKS, Njie R, Goldin RD, Taylor-Robinson SD. Hepatic steatosis and fibrosis: Non-invasive assessment. World J Gastroenterol 2016; 22:9880-9897. [PMID: 28018096 PMCID: PMC5143756 DOI: 10.3748/wjg.v22.i45.9880] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 10/10/2016] [Accepted: 11/16/2016] [Indexed: 02/06/2023] Open
Abstract
Chronic liver disease is a major cause of morbidity and mortality worldwide and usually develops over many years, as a result of chronic inflammation and scarring, resulting in end-stage liver disease and its complications. The progression of disease is characterised by ongoing inflammation and consequent fibrosis, although hepatic steatosis is increasingly being recognised as an important pathological feature of disease, rather than being simply an innocent bystander. However, the current gold standard method of quantifying and staging liver disease, histological analysis by liver biopsy, has several limitations and can have associated morbidity and even mortality. Therefore, there is a clear need for safe and non-invasive assessment modalities to determine hepatic steatosis, inflammation and fibrosis. This review covers key mechanisms and the importance of fibrosis and steatosis in the progression of liver disease. We address non-invasive imaging and blood biomarker assessments that can be used as an alternative to information gained on liver biopsy.
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18
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Kelly D, Verkade HJ, Rajanayagam J, McKiernan P, Mazariegos G, Hübscher S. Late graft hepatitis and fibrosis in pediatric liver allograft recipients: Current concepts and future developments. Liver Transpl 2016; 22:1593-1602. [PMID: 27543906 DOI: 10.1002/lt.24616] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 08/06/2016] [Indexed: 02/07/2023]
Abstract
Liver transplantation (LT) in children now has a 20-year survival of >80%, but the longterm outcome of these grafts remains uncertain. Serial protocol liver biopsies after transplantation from several pediatric centres have demonstrated the gradual development of unexplained graft inflammation ("idiopathic" posttransplant hepatitis; IPTH) and graft fibrosis in biopsies obtained >12 months post-LT in children with good graft function and (near) normal liver biochemistry. Although the clinical significance of these findings is uncertain, there is evidence to suggest that IPTH may be a form of rejection or chronic antibody-mediated rejection as it is associated with the presence of auto/alloantibodies; de novo Class II donor-specific HLA antibodies (DSA); previous episodes of rejection, and may improve or be prevented with increased immunosuppression. Currently, the only method of diagnosing either hepatitis or fibrosis has been by serial protocol biopsies as neither serum markers of fibrosis nor noninvasive methods to detect fibrosis such as transient elastography (TE) are sufficiently validated in children. This review will focus on the diagnosis and management of idiopathic posttransplant hepatitis and graft fibrosis, discuss current methods for detecting graft injury, and potential mechanisms for their development. Liver Transplantation 22 1593-1602 2016 AASLD.
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Affiliation(s)
- Deirdre Kelly
- Liver Unit, Birmingham Children's Hospital and University of Birmingham, Birmingham, United Kingdom.
| | - Henkjan J Verkade
- Department of Pediatrics, Beatrix Children's Hospital/University Medical Center, Groningen University, Groningen, the Netherlands
| | | | - Patrick McKiernan
- Liver Unit, Birmingham Children's Hospital and University of Birmingham, Birmingham, United Kingdom
| | - George Mazariegos
- Hillman Center for Pediatric Transplantation, Children's Hospital of Pittsburgh, Pittsburgh, PA
| | - Stefan Hübscher
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, United Kingdom.,Department of Cellular Pathology, University Hospitals Birmingham, National Health Service Foundation Trust, Birmingham, United Kingdom
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Abstract
The diagnostics of diffuse liver disease traditionally rely on liver biopsies and histopathological analysis of tissue specimens. However, a liver biopsy is invasive and carries some non-negligible risks, especially for patients with decreased liver function and those requiring repeated follow-up examinations. Over the last decades, magnetic resonance imaging (MRI) has developed into a valuable tool for the non-invasive characterization of focal liver lesions and diseases of the bile ducts. Recently, several MRI methods have been developed and clinically evaluated that also allow the diagnostics and staging of diffuse liver diseases, e.g. non-alcoholic fatty liver disease, hepatitis, hepatic fibrosis, liver cirrhosis, hemochromatosis and hemosiderosis. The sequelae of diffuse liver diseases, such as a decreased liver functional reserve or portal hypertension, can also be detected and quantified by modern MRI methods. This article provides the reader with the basic principles of functional MRI of the liver and discusses the importance in a clinical context.
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20
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Lizaola B, Bonder A, Tapper EB, Afdhal N. Role of Noninvasive Fibrosis Methods in Management of Chronic Hepatitis B Virus. ACTA ACUST UNITED AC 2016. [DOI: 10.1007/s11901-016-0311-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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21
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Magnetic Resonance Elastography for the Evaluation of Liver Fibrosis in Chronic Hepatitis B and C by Using Both Gradient-Recalled Echo and Spin-Echo Echo Planar Imaging: A Prospective Study. Am J Gastroenterol 2016; 111:823-33. [PMID: 26977760 DOI: 10.1038/ajg.2016.56] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 01/02/2016] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Magnetic resonance elastography (MRE) with three-dimensional spin-echo echo planar imaging (3D-SE-EPI) is a newly emerging noninvasive method for assessing liver fibrosis. We hypothesized that 3D-SE-EPI might have better diagnostic accuracy than conventional two-dimensional gradient-recalled echo (2D-GRE). METHODS We prospectively included 179 consecutive patients with chronic hepatitis B (CHB) or C (CHC) who underwent both MRE and liver biopsy. Liver stiffness was measured by both 3D-SE-EPI and 2D-GRE for staging biopsy-proven liver fibrosis (using METAVIR scores). A receiver-operating characteristic analysis using the area under the receiver-operating characteristic curve (AUC) was used to compare the diagnostic performance in predicting liver fibrosis between these two techniques, and compared them to serum markers of fibrosis. RESULTS The technical failure rate of 3D-SE-EPI (2.2%, n=4/179) was lower compared with 2D-GRE (8.3%, n=15/179). The stiffness measured by 3D-SE-EPI was slightly lower compared with 2D-GRE, with the mean difference of 0.57 kPa (Bland and Altman plot, 95% limits of agreement: -0.32 and 1.45 kPa). AUCs for the characterization of ≥F1, ≥F2, ≥F3, and F4 were 0.957 (95% confidence interval (CI): 0.913-0.983), 0.971 (0.932-0.991), 0.991 (0.961-0.999), and 0.979 (0.942-0.995) for 3D-SE-EPI, which was slightly higher compared with the AUCs for 2D-GRE at each fibrosis stage (0.948 (0.901-0.977), 0.959 (0.915-0.981), 0.979 (0.943-0.995), and 0.976 (0.938-0.994), respectively), although none reached statistical significance (P=0.160-0.585). In an "intention-to-diagnose" analysis, the diagnostic accuracy (the proportion of well-classified patients) by EPI (86.7-91.3%, n=169) was higher compared with GRE (80.9-82.1%, n=158) after applying optimal cutoffs. Both 3D-SE-EPI and 2D-GRE performed better than serum fibrosis markers. CONCLUSIONS With respect to 2D-GRE, 3D-SE-EPI has the advantage of lower failure rate with equivalent high diagnostic performance for staging liver fibrosis in CHB/CHC patients, and thus more helpful for those challenging cases in 2D-GRE.
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22
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Singh S, Venkatesh SK, Loomba R, Wang Z, Sirlin C, Chen J, Yin M, Miller FH, Low RN, Hassanein T, Godfrey EM, Asbach P, Murad MH, Lomas DJ, Talwalkar JA, Ehman RL. Magnetic resonance elastography for staging liver fibrosis in non-alcoholic fatty liver disease: a diagnostic accuracy systematic review and individual participant data pooled analysis. Eur Radiol 2016; 26:1431-40. [PMID: 26314479 PMCID: PMC5051267 DOI: 10.1007/s00330-015-3949-z] [Citation(s) in RCA: 167] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 06/30/2015] [Accepted: 07/27/2015] [Indexed: 02/07/2023]
Abstract
OBJECTIVES We conducted an individual participant data (IPD) pooled analysis on diagnostic accuracy of MRE to detect fibrosis stage in patients with non-alcoholic fatty liver disease (NAFLD). METHODS Through a systematic literature search, we identified studies of MRE (at 60-62.5 Hz) for staging fibrosis in patients with NAFLD, using liver biopsy as gold standard, and contacted study authors for IPD. Through pooled analysis, we calculated the cluster-adjusted AUROC, sensitivity and specificity of MRE for any (≥stage 1), significant (≥stage 2) and advanced (≥stage 3) fibrosis and cirrhosis (stage 4). RESULTS We included nine studies with 232 patients with NAFLD (mean age, 51 ± 13 years; 37.5% males; mean BMI, 33.5 ± 6.7 kg/m(2); interval between MRE and biopsy <1 year, 98.3%). Fibrosis stage distribution (stage 0/1/2/3/4) was 33.6, 32.3, 10.8, 12.9 and 10.4%, respectively. Mean AUROC (and 95% CIs) for diagnosis of any, significant or advanced fibrosis and cirrhosis was 0.86 (0.82-0.90), 0.87 (0.82-0.93), 0.90 (0.84-0.94) and 0.91 (0.76-0.95), respectively. Similar diagnostic performance was observed in stratified analysis based on sex, obesity and degree of inflammation. CONCLUSIONS MRE has high diagnostic accuracy for detection of fibrosis in NAFLD, independent of BMI and degree of inflammation. KEY POINTS • MRE has high diagnostic accuracy for detection of fibrosis in NAFLD. • BMI does not significantly affect accuracy of MRE in NAFLD. • Inflammation had no significant influence on MRE performance in NAFLD for fibrosis.
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Affiliation(s)
- Siddharth Singh
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA
| | - Sudhakar K Venkatesh
- Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, 55905, USA.
| | - Rohit Loomba
- NAFLD Translational Research Unit, Division of Gastroenterology and Hepatology, Department of Medicine, University of California, San Diego, CA, USA
| | - Zhen Wang
- Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, Mayo Clinic, Rochester, MN, USA
| | - Claude Sirlin
- Liver Imaging Group, Department of Radiology, University of California, San Diego, CA, USA
| | - Jun Chen
- Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, 55905, USA
| | - Meng Yin
- Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, 55905, USA
| | - Frank H Miller
- Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | | | | | | | - Patrick Asbach
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Mohammad Hassan Murad
- Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, Mayo Clinic, Rochester, MN, USA
| | - David J Lomas
- Department of Radiology, Addenbrooke's Hospital, Cambridge, UK
| | - Jayant A Talwalkar
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, MN, USA
| | - Richard L Ehman
- Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, 55905, USA
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Low G, Kruse SA, Lomas DJ. General review of magnetic resonance elastography. World J Radiol 2016; 8:59-72. [PMID: 26834944 PMCID: PMC4731349 DOI: 10.4329/wjr.v8.i1.59] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 11/14/2015] [Accepted: 12/04/2015] [Indexed: 02/06/2023] Open
Abstract
Magnetic resonance elastography (MRE) is an innovative imaging technique for the non-invasive quantification of the biomechanical properties of soft tissues via the direct visualization of propagating shear waves in vivo using a modified phase-contrast magnetic resonance imaging (MRI) sequence. Fundamentally, MRE employs the same physical property that physicians utilize when performing manual palpation - that healthy and diseased tissues can be differentiated on the basis of widely differing mechanical stiffness. By performing “virtual palpation”, MRE is able to provide information that is beyond the capabilities of conventional morphologic imaging modalities. In an era of increasing adoption of multi-parametric imaging approaches for solving complex problems, MRE can be seamlessly incorporated into a standard MRI examination to provide a rapid, reliable and comprehensive imaging evaluation at a single patient appointment. Originally described by the Mayo Clinic in 1995, the technique represents the most accurate non-invasive method for the detection and staging of liver fibrosis and is currently performed in more than 100 centers worldwide. In this general review, the mechanical properties of soft tissues, principles of MRE, clinical applications of MRE in the liver and beyond, and limitations and future directions of this discipline -are discussed. Selected diagrams and images are provided for illustration.
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Abstract
Many diseases cause substantial changes in the mechanical properties of tissue, and this provides motivation for developing methods to noninvasively assess the stiffness of tissue using imaging technology. Magnetic resonance elastography (MRE) has emerged as a versatile MRI-based technique, based on direct visualization of propagating shear waves in the tissues. The most established clinical application of MRE in the abdomen is in chronic liver disease. MRE is currently regarded as the most accurate noninvasive technique for detection and staging of liver fibrosis. Increasing experience and ongoing research is leading to exploration of applications in other abdominal organs. In this review article, the current use of MRE in liver disease and the potential future applications of this technology in other parts of the abdomen are surveyed.
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Crossan C, Tsochatzis EA, Longworth L, Gurusamy K, Davidson B, Rodríguez-Perálvarez M, Mantzoukis K, O'Brien J, Thalassinos E, Papastergiou V, Burroughs A. Cost-effectiveness of non-invasive methods for assessment and monitoring of liver fibrosis and cirrhosis in patients with chronic liver disease: systematic review and economic evaluation. Health Technol Assess 2015; 19:1-409, v-vi. [PMID: 25633908 DOI: 10.3310/hta19090] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Liver biopsy is the reference standard for diagnosing the extent of fibrosis in chronic liver disease; however, it is invasive, with the potential for serious complications. Alternatives to biopsy include non-invasive liver tests (NILTs); however, the cost-effectiveness of these needs to be established. OBJECTIVE To assess the diagnostic accuracy and cost-effectiveness of NILTs in patients with chronic liver disease. DATA SOURCES We searched various databases from 1998 to April 2012, recent conference proceedings and reference lists. METHODS We included studies that assessed the diagnostic accuracy of NILTs using liver biopsy as the reference standard. Diagnostic studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Meta-analysis was conducted using the bivariate random-effects model with correlation between sensitivity and specificity (whenever possible). Decision models were used to evaluate the cost-effectiveness of the NILTs. Expected costs were estimated using a NHS perspective and health outcomes were measured as quality-adjusted life-years (QALYs). Markov models were developed to estimate long-term costs and QALYs following testing, and antiviral treatment where indicated, for chronic hepatitis B (HBV) and chronic hepatitis C (HCV). NILTs were compared with each other, sequential testing strategies, biopsy and strategies including no testing. For alcoholic liver disease (ALD), we assessed the cost-effectiveness of NILTs in the context of potentially increasing abstinence from alcohol. Owing to a lack of data and treatments specifically for fibrosis in patients with non-alcoholic fatty liver disease (NAFLD), the analysis was limited to an incremental cost per correct diagnosis. An analysis of NILTs to identify patients with cirrhosis for increased monitoring was also conducted. RESULTS Given a cost-effectiveness threshold of £20,000 per QALY, treating everyone with HCV without prior testing was cost-effective with an incremental cost-effectiveness ratio (ICER) of £9204. This was robust in most sensitivity analyses but sensitive to the extent of treatment benefit for patients with mild fibrosis. For HBV [hepatitis B e antigen (HBeAg)-negative)] this strategy had an ICER of £28,137, which was cost-effective only if the upper bound of the standard UK cost-effectiveness threshold range (£30,000) is acceptable. For HBeAg-positive disease, two NILTs applied sequentially (hyaluronic acid and magnetic resonance elastography) were cost-effective at a £20,000 threshold (ICER: £19,612); however, the results were highly uncertain, with several test strategies having similar expected outcomes and costs. For patients with ALD, liver biopsy was the cost-effective strategy, with an ICER of £822. LIMITATIONS A substantial number of tests had only one study from which diagnostic accuracy was derived; therefore, there is a high risk of bias. Most NILTs did not have validated cut-offs for diagnosis of specific fibrosis stages. The findings of the ALD model were dependent on assuptions about abstinence rates assumptions and the modelling approach for NAFLD was hindered by the lack of evidence on clinically effective treatments. CONCLUSIONS Treating everyone without NILTs is cost-effective for patients with HCV, but only for HBeAg-negative if the higher cost-effectiveness threshold is appropriate. For HBeAg-positive, two NILTs applied sequentially were cost-effective but highly uncertain. Further evidence for treatment effectiveness is required for ALD and NAFLD. STUDY REGISTRATION This study is registered as PROSPERO CRD42011001561. FUNDING The National Institute for Health Research Health Technology Assessment programme.
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Affiliation(s)
- Catriona Crossan
- Health Economics Research Group, Brunel University London, Uxbridge, UK
| | - Emmanuel A Tsochatzis
- Sheila Sherlock Liver Centre, Royal Free Hospital and UCL Institute for Liver and Digestive Health, Royal Free Hospital, London, UK
| | - Louise Longworth
- Health Economics Research Group, Brunel University London, Uxbridge, UK
| | | | | | - Manuel Rodríguez-Perálvarez
- Sheila Sherlock Liver Centre, Royal Free Hospital and UCL Institute for Liver and Digestive Health, Royal Free Hospital, London, UK
| | - Konstantinos Mantzoukis
- Sheila Sherlock Liver Centre, Royal Free Hospital and UCL Institute for Liver and Digestive Health, Royal Free Hospital, London, UK
| | - Julia O'Brien
- Sheila Sherlock Liver Centre, Royal Free Hospital and UCL Institute for Liver and Digestive Health, Royal Free Hospital, London, UK
| | - Evangelos Thalassinos
- Sheila Sherlock Liver Centre, Royal Free Hospital and UCL Institute for Liver and Digestive Health, Royal Free Hospital, London, UK
| | - Vassilios Papastergiou
- Sheila Sherlock Liver Centre, Royal Free Hospital and UCL Institute for Liver and Digestive Health, Royal Free Hospital, London, UK
| | - Andrew Burroughs
- Sheila Sherlock Liver Centre, Royal Free Hospital and UCL Institute for Liver and Digestive Health, Royal Free Hospital, London, UK
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Huhdanpaa HT, Zhang P, Krishnamurthy VN, Douville C, Enchakolody B, Chou C, Ethiraj S, Wang S, Su GL. Quantitative detection of cirrhosis: towards the development of computer-assisted detection method. J Digit Imaging 2015; 27:601-9. [PMID: 24811859 DOI: 10.1007/s10278-014-9696-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
There are distinct morphologic features of cirrhosis on CT examinations; however, such impressions may be subtle or subjective. The purpose of this study is to build a computer-aided diagnosis (CAD) method to help radiologists with this diagnosis. One hundred sixty-seven abdominal CT examinations were randomly divided into training (n = 88) and validation (n = 79) sets. Livers were analyzed for morphological markers of cirrhosis and logistic regression models were created. Using the area under curve (AUC) for model performance, the best model had 0.89 for the training set and 0.85 for the validation set. For radiology reports, sensitivity of reporting cirrhosis was 0.45 and specificity 0.99. Using the predictive model adjunctively, radiologists' sensitivity increased to 0.63 and specificity slightly decreased to 0.97. This study demonstrates that quantifying morphological features in livers may be utilized for diagnosing cirrhosis and for developing a CAD method for it.
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Affiliation(s)
- Hannu T Huhdanpaa
- Department of Radiology, University of Southern California, 1500 San Pablo Street, Second Floor Imaging, Los Angeles, CA, 90033, USA,
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Makowski MR, Jonczyk M, Streitparth F, Guettler F, Rathke H, Suttmeyer B, Albrecht L, Teichgräber UK, Hamm B, de Bucourt M. Interactive near-real-time high-resolution imaging for MR-guided lumbar interventions using ZOOM imaging in an open 1.0 Tesla MRI system--initial experience. BIOMED ENG-BIOMED TE 2015; 60:533-9. [PMID: 25830904 DOI: 10.1515/bmt-2014-0118] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 03/02/2015] [Indexed: 01/20/2023]
Abstract
PURPOSE Different techniques for magnetic resonance-guided lumbar interventions have been introduced in recent years. Appropriate pulse sequence design is crucial since high spatial resolution often comes at the cost of lower temporal resolution. The purpose of this study was to evaluate the value of accelerated reduced field of view (ZOOM)-based imaging sequences for lumbar interventions. METHODS ZOOM imaging was used in 31 interventions (periradicular, facet joint, epidural infiltrations, and discography) performed in 24 patients (10 women, 14 men; age 43 ± 13.3 years). Signal-to-noise ratio and contrast-to-noise ratio (CNR) were determined and retrospectively compared with standard preinterventional (T2 weighted), peri-interventional (proton density), and postinterventional (spectral presaturation with inversion recovery [SPIR]) imaging. Needle artifacts were assessed by direct measurement as well as with parallel and perpendicular needle profiles. Puncture times were compared to similar interventions previously performed in our department. RESULTS No significant differences in signal intensities (standard/ZOOM: 152.0/151.6; p=0.136) and CNR values (2.0/4.0; p=0.487) were identified for T2-weighted sequences. The needle artifact signal intensity was comparable (648.1/747.5; p=0.172) for peri-interventional imaging. Standard interventional (fat needle: 43.8/23.4; p<0.001; muscle needle: 6.2/2.4; p<0.001) and SPIR sequences (43.3/13.9; p=0.010) showed a higher CNR than corresponding ZOOM sequences did. Needle artifacts were larger in ZOOM (2.4 mm/2.9 mm; p=0.005). The profiles revealed that ZOOM imaging delivers more overall signal intensity. The turning points of both profiles were comparable. ZOOM reduced intervention times significantly (329.1 s/228.5 s; p=0.026). CONCLUSION ZOOM imaging is a feasible interactive sequence for lumbar interventions. It ameliorates the tradeoff between image quality and temporal resolution. Moreover, the sequence design reduces intervention times significantly.
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Singh S, Venkatesh SK, Wang Z, Miller FH, Motosugi U, Low RN, Hassanein T, Asbach P, Godfrey EM, Yin M, Chen J, Keaveny AP, Bridges M, Bohte A, Murad MH, Lomas DJ, Talwalkar JA, Ehman RL. Diagnostic performance of magnetic resonance elastography in staging liver fibrosis: a systematic review and meta-analysis of individual participant data. Clin Gastroenterol Hepatol 2015; 13:440-451.e6. [PMID: 25305349 PMCID: PMC4333001 DOI: 10.1016/j.cgh.2014.09.046] [Citation(s) in RCA: 378] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 09/12/2014] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Magnetic resonance elastography (MRE) is a noninvasive tool for staging liver fibrosis. We conducted a meta-analysis of individual participant data collected from published studies to assess the diagnostic accuracy of MRE for staging liver fibrosis in patients with chronic liver diseases (CLD). METHODS Through a systematic literature search of multiple databases (2003-2013), we identified studies on diagnostic performance of MRE for staging liver fibrosis in patients with CLD with native anatomy, using liver biopsy as the standard. We contacted study authors to collect data on each participant's age, sex, body mass index (BMI), liver stiffness (measured by MRE), fibrosis stage, staging system used, degree of inflammation, etiology of CLD, and interval between MRE and biopsy. Through a pooled analysis, we calculated cluster-adjusted area under the receiver-operating curve, sensitivity, and specificity of MRE for any fibrosis (≥stage 1), significant fibrosis (≥stage 2), advanced fibrosis (≥stage 3), and cirrhosis (stage 4). RESULTS We analyzed data from 12 retrospective studies, comprising 697 patients (mean age, 55 ± 13 y; 59.4% male; mean BMI, 26.9 ± 6.7 kg/m(2); 92.1% with <1 year interval between MRE and biopsy; and 47.1% with hepatitis C). Overall, 19.5%, 19.4%, 15.5%, 15.9%, and 29.7% patients had stage 0, 1, 2, 3, and 4 fibrosis, respectively. The mean area under the receiver-operating curve values (and 95% confidence intervals) for the diagnosis of any (≥stage 1), significant (≥stage 2), advanced fibrosis (≥stage 3), and cirrhosis, were as follows: 0.84 (0.76-0.92), 0.88 (0.84-0.91), 0.93 (0.90-0.95), and 0.92 (0.90-0.94), respectively. A similar diagnostic performance was observed in stratified analysis based on sex, obesity, and etiology of CLD. The overall rate of failure of MRE was 4.3%. CONCLUSIONS Based on a pooled analysis of data from individual participants, MRE has a high accuracy for the diagnosis of significant or advanced fibrosis and cirrhosis, independent of BMI and etiology of CLD. Prospective studies are warranted to better understand the diagnostic performance of MRE.
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Affiliation(s)
- Siddharth Singh
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
| | | | - Zhen Wang
- Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, Mayo Clinic, Rochester, Minnesota
| | - Frank H Miller
- Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Utaroh Motosugi
- Department of Radiology, University of Yamanashi, Chuo-shi, Yamanashi, Japan
| | - Russell N Low
- Sharp and Children's Magnetic Resonance Imaging Center, San Diego, California
| | | | - Patrick Asbach
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Edmund M Godfrey
- Department of Radiology, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Meng Yin
- Department of Radiology, Mayo Clinic, Rochester, Minnesota
| | - Jun Chen
- Department of Radiology, Mayo Clinic, Rochester, Minnesota
| | | | - Mellena Bridges
- Department of Radiology, Department of Medicine, Mayo Clinic, Jacksonville, Florida
| | - Anneloes Bohte
- Department of Radiology, Academic Medical Center, Amsterdam, The Netherlands
| | - Mohammad Hassan Murad
- Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery, Mayo Clinic, Rochester, Minnesota
| | - David J Lomas
- Department of Radiology, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Jayant A Talwalkar
- Division of Gastroenterology and Hepatology, Mayo Clinic, Rochester, Minnesota
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Jonczyk M, Hamm B, Heinrich A, Thomas A, Rathke H, Schnackenburg B, Güttler F, Teichgräber UKM, de Bucourt M. Initial clinical experience with a quadrupole butterfly coil for spinal injection interventions in an open MRI system at 1.0 tesla. ACTA ACUST UNITED AC 2015; 59:39-45. [PMID: 24152888 DOI: 10.1515/bmt-2013-0066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2013] [Accepted: 10/01/2013] [Indexed: 11/15/2022]
Abstract
PURPOSE To report our initial clinical experience with a new magnetic resonance imaging (MRI) quadrupole coil that allows interventions in prone position. MATERIALS AND METHODS Fifteen patients (seven women, eight men; average age, 42.8 years) were treated in the same 1.0-Tesla Panorama High Field Open (HFO) MRI system (Panorama HFO) using a quadrupole butterfly coil (Bfly) and compared with 15 patients matched for sex, age, and MR intervention using the MultiPurposeL coil (MPL), performed in conventional lateral decubitus position (all, Philips Medical Systems, Best, The Netherlands). All interventions were performed with a near-real-time proton density turbo spin echo (PD TSE) sequence (time to repeat/time to echo/flip angle/acquisition time, 600 ms/10 ms/90°/3 s/image). Qualitative and quantitative image analyses were performed, including signal intensity, signal-to-noise and contrast-to-noise ratio (SNR, CNR), contrast, and full width at half maximum (FWHM) measurements. RESULTS Contrast differed significantly between the needle and muscles (Bfly 0.27/MPL 0.17), as well as the needle and periradicular fat (0.13/0.24) during the intervention (both, p=0.029), as well as the CNR between muscles and the needle (10.61/5.23; p=0.010), although the FWHM values did not (2.4/2.2; p=0.754). The signal intensity of the needle in interventional imaging (1152.9/793.2; p=0.006) and the postinterventional SNR values of subcutaneous fat (15.3/28.6; p=0.007), muscles (6.6/11.8; p=0.011), and the CNR between these tissues (8.7/17.5; p=0.004) yielded significant differences. CONCLUSION The new coil is a valid alternative for MR-guided interventions in an open MRI system at 1.0 tesla, especially if patients cannot (or prefer not to) be in a lateral decubitus position or if prone positioning yields better access to the target zone.
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Abstract
Chronic HCV infection is the leading indication for liver transplantation. However, as a result of HCV recurrence, patient and graft survival after liver transplantation are inferior compared with other indications for transplantation. HCV recurrence after liver transplantation is associated with considerable mortality and morbidity. The development of HCV-related fibrosis is accelerated after liver transplantation, which is influenced by a combination of factors related to the virus, donor, recipient, surgery and immunosuppression. Successful antiviral therapy is the only treatment that can attenuate fibrosis. The advent of direct-acting antiviral agents (DAAs) has changed the therapeutic landscape for the treatment of patients with HCV. DAAs have improved tolerability, and can potentially be used without PEG-IFN for a shorter time than previous therapies, which should result in better outcomes. In this Review, we describe the important risk factors that influence HCV recurrence after liver transplantation, highlighting the mechanisms of fibrosis and the integral role of hepatic stellate cells. Indirect and direct assessment of fibrosis, in addition to new antiviral therapies, are also discussed.
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Su LN, Guo SL, Li BX, Yang P. Diagnostic value of magnetic resonance elastography for detecting and staging of hepatic fibrosis: a meta-analysis. Clin Radiol 2014; 69:e545-52. [PMID: 25300557 DOI: 10.1016/j.crad.2014.09.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 08/25/2014] [Accepted: 09/04/2014] [Indexed: 12/26/2022]
Abstract
AIM A meta-analysis was performed to evaluate the diagnostic value of magnetic resonance elastography (MRE) in detecting and staging hepatic fibrosis. MATERIALS AND METHODS A systematic search of PubMed, EMBASE, Web of Science, and Cochrane Library Database up to October 2013 was undertaken to find studies on the evaluation of MRE in patients suspected of hepatic fibrosis. Data from the articles were analysed using Meta-disc 1.4 and Stata 12.0 software. The sensitivity, specificity, and area under the summary receiver operating characteristic (ROC) curve (AUROC) were pooled for all stages of hepatic fibrosis (F ≥ 1, F ≥ 2, F ≥ 3, and F = 4). Publication bias was assessed through the Deeks' funnel plot asymmetry tests. RESULTS Thirteen studies comprising 989 patients met the inclusion criteria. The pooled sensitivity and specificity for F ≥ 1, F ≥ 2, F ≥ 3, and F = 4 were 0.87 (95% CI = 0.84-0.89) and 0.92 (95% CI = 0.87-0.96), 0.87 (95% CI = 0.84-0.90) and 0.92 (95% CI = 0.89-0.95), 0.88 (95% CI = 0.85-0.91) and 0.91 (95% CI = 0.88-0.93), 0.91 (95% CI = 0.87-0.94) and 0.92 (95% CI = 0.89-0.94), respectively. The pooled AUROC for F ≥ 1, F ≥ 2, F ≥ 3, and F = 4 were 0.9502, 0.9663, 0.9644, and 0.9768, respectively. The non-significant slope of Deeks' funnel plot asymmetry tests indicated that no significant bias was found. CONCLUSIONS MRE has a high diagnostic accuracy for the quantitative detection and staging of hepatic fibrosis.
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Affiliation(s)
- L-N Su
- Department of Radiology, The First Clinical Medical School of Lanzhou University, Lanzhou 730000, China
| | - S-L Guo
- Department of Radiology, The First Clinical Medical School of Lanzhou University, Lanzhou 730000, China.
| | - B-X Li
- Department of Radiology, The First Clinical Medical School of Lanzhou University, Lanzhou 730000, China
| | - P Yang
- Department of Radiology, The First Clinical Medical School of Lanzhou University, Lanzhou 730000, China
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Abstract
Magnetic resonance elastography (MRE) assesses tissue stiffness in vivo by imaging propagating shear waves through the tissues and processing the wave information. MRE is a robust technology with excellent technical success; is applicable in almost all patients and body habitus; and has excellent reproducibility, repeatability, and interobserver agreement for assessing liver stiffness. It is currently the most accurate noninvasive technique for detection and staging of liver fibrosis and has the potential to replace liver biopsy. This article describes the principles and technique of MRE, current clinical applications, and emerging clinical indications.
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Affiliation(s)
- Sudhakar Kundapur Venkatesh
- Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
| | - Richard L Ehman
- Department of Radiology, Mayo Clinic College of Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
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Abstract
In this article, functional magnetic resonance (MR) imaging techniques in the abdomen are discussed. Diffusion-weighted imaging (DWI) increases the confidence in detecting and characterizing focal hepatic lesions. The potential uses of DWI in kidneys, adrenal glands, bowel, and pancreas are outlined. Studies have shown potential use of quantitative dynamic contrast-enhanced MR imaging parameters, such as K(trans), in predicting outcomes in cancer therapy. MR elastography is considered to be a useful tool in staging liver fibrosis. A major issue with all functional MR imaging techniques is the lack of standardization of the protocol.
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Affiliation(s)
- Kumar Sandrasegaran
- Department of Radiology, Indiana University School of Medicine, 550 N University Blvd, UH 0279, Indianapolis, IN 46202, USA.
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Girometti R, Como G, Bazzocchi M, Zuiani C. Post-operative imaging in liver transplantation: State-of-the-art and future perspectives. World J Gastroenterol 2014; 20:6180-6200. [PMID: 24876739 PMCID: PMC4033456 DOI: 10.3748/wjg.v20.i20.6180] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 01/20/2014] [Indexed: 02/06/2023] Open
Abstract
Orthotopic liver transplantation (OLT) represents a major treatment for end-stage chronic liver disease, as well as selected cases of hepatocellular carcinoma and acute liver failure. The ever-increasing development of imaging modalities significantly contributed, over the last decades, to the management of recipients both in the pre-operative and post-operative period, thus impacting on graft and patients survival. When properly used, imaging modalities such as ultrasound, multidetector computed tomography, magnetic resonance imaging (MRI) and procedures of direct cholangiography are capable to provide rapid and reliable recognition and treatment of vascular and biliary complications occurring after OLT. Less defined is the role for imaging in assessing primary graft dysfunction (including rejection) or chronic allograft disease after OLT, e.g., hepatitis C virus (HCV) recurrence. This paper: (1) describes specific characteristic of the above imaging modalities and the rationale for their use in clinical practice; (2) illustrates main imaging findings related to post-OLT complications in adult patients; and (3) reviews future perspectives emerging in the surveillance of recipients with HCV recurrence, with special emphasis on MRI.
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Abstract
Magnetic resonance elastography (MRE) has been successfully implemented in the assessment of diffuse liver diseases. Currently, MRE is the most accurate noninvasive technique for detection and staging of liver fibrosis with a potential to replace liver biopsy. Magnetic resonance elastography is able to differentiate isolated fatty liver disease from steatohepatitis with or without fibrosis. Potential clinical applications include the differentiation of benign and malignant focal liver masses and the assessment of treatment response in diffuse liver diseases.
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Crespo S, Bridges M, Nakhleh R, McPhail A, Pungpapong S, Keaveny AP. Non-invasive assessment of liver fibrosis using magnetic resonance elastography in liver transplant recipients with hepatitis C. Clin Transplant 2013; 27:652-8. [PMID: 23837611 DOI: 10.1111/ctr.12180] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/04/2013] [Indexed: 12/24/2022]
Abstract
BACKGROUND Liver biopsy has been the reference standard when evaluating fibrosis due to recurrent hepatitis after liver transplantation. Magnetic resonance elastography estimates liver stiffness, correlating to fibrosis. AIM To investigate the utility of elastography in staging liver fibrosis in transplant recipients with hepatitis C. METHODS Fifty-four patients, ≥12 months post-transplant, underwent elastography within three months of biopsy. Discriminatory capability for METAVIR fibrosis stages F0-2 vs. F3-4 and receiver operating characteristic curve (ROC) analysis were determined. RESULTS On biopsy, 27 patients had METAVIR fibrosis score 0-1; 12 had a 3 or 4. There was significant correlation between histologic fibrosis and shear stiffness (R² = 0.588, p < 0.0001). Using a cutoff value of 3.5 kPa, elastography was 91% sensitive and 72% specific in differentiating fibrosis scores of ≥3 from 0 to 1. The AUC of elastography in predicting a fibrosis score of ≥3 was 0.92. Multivariate analysis revealed no correlation between the grade of histologic inflammation and liver stiffness measured by magnetic resonance elastography (R² = 0.265, p = 0.47). CONCLUSION Magnetic resonance elastography is an accurate non-invasive technique for excluding stage ≥3 graft in recipients with hepatitis C.
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Affiliation(s)
- Sergio Crespo
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Jacksonville, FL, USA
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Durango E, Dietrich C, Seitz HK, Kunz CU, Pomier-Layrargues GT, Duarte-Rojo A, Beaton M, Elkhashab M, Myers RP, Mueller S. Direct comparison of the FibroScan XL and M probes for assessment of liver fibrosis in obese and nonobese patients. ACTA ACUST UNITED AC 2013. [PMID: 24696623 DOI: 10.10.2147/hmer.s45234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND A novel Fibroscan XL probe has recently been introduced and validated for obese patients, and has a diagnostic accuracy comparable with that of the standard M probe. The aim of this study was to analyze and understand the differences between these two probes in nonobese patients, to identify underlying causes for these differences, and to develop a practical algorithm to translate results for the XL probe to those for the M probe. METHODS AND RESULTS Both probes were directly compared first in copolymer phantoms of varying stiffness (4.8, 11, and 40 kPa) and then in 371 obese and nonobese patients (body mass index, range 17.2-72.4) from German (n = 129) and Canadian (n = 242) centers. Liver stiffness values for both probes correlated better in phantoms than in patients (r = 0.98 versus 0.82, P < 0.001). Significantly more patients could be measured successfully using the XL probe than the M probe (98.4% versus 85.2%, respectively, P < 0.001) while the M probe produced a smaller interquartile range (21% versus 32%). Failure of the M probe to measure liver stiffness was not only observed in patients with a high body mass index and long skin-liver capsule distance but also in some nonobese patients (n = 10) due to quenching of the signal from subcutaneous fat tissue. In contrast with the phantoms, the XL probe consistently produced approximately 20% lower liver stiffness values in humans compared with the M probe. A long skin-liver capsule distance and a high degree of steatosis were responsible for this discordance. Adjustment of cutoff values for the XL probe (<5.5, 5.5-7, 7-10, and >10 kPa for F0, F1-2, F3, and F4 fibrosis, respectively) significantly improved agreement between the two probes from r = 0.655 to 0.679. CONCLUSION Liver stiffness can be measured in significantly more obese and nonobese patients using the XL probe than the M probe. However, the XL probe is less accurate and adjusted cutoff values are required.
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Affiliation(s)
- Esteban Durango
- Department of Medicine and Center for Alcohol Research, Liver Disease and Nutrition, Salem Medical Center, Germany
| | - Christian Dietrich
- Department of Medicine and Center for Alcohol Research, Liver Disease and Nutrition, Salem Medical Center, Germany
| | - Helmut Karl Seitz
- Department of Medicine and Center for Alcohol Research, Liver Disease and Nutrition, Salem Medical Center, Germany
| | - Cornelia Ursula Kunz
- Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany
| | | | | | - Melanie Beaton
- Multi-Organ Transplant Unit, University of Western Ontario, London, Ontario, Canada
| | | | - Robert P Myers
- Liver Unit, Division of Gastroenterology and Hepatology, Department of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Sebastian Mueller
- Department of Medicine and Center for Alcohol Research, Liver Disease and Nutrition, Salem Medical Center, Germany ; Liver Unit, Centre Hospitalier de l'Université de Montréal, Hôpital Saint-Luc, Montréal, Quebec, Canada
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Durango E, Dietrich C, Seitz HK, Kunz CU, Pomier-Layrargues GT, Duarte-Rojo A, Beaton M, Elkhashab M, Myers RP, Mueller S. Direct comparison of the FibroScan XL and M probes for assessment of liver fibrosis in obese and nonobese patients. Hepat Med 2013; 5:43-52. [PMID: 24696623 PMCID: PMC3953737 DOI: 10.2147/hmer.s45234] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Background A novel Fibroscan XL probe has recently been introduced and validated for obese patients, and has a diagnostic accuracy comparable with that of the standard M probe. The aim of this study was to analyze and understand the differences between these two probes in nonobese patients, to identify underlying causes for these differences, and to develop a practical algorithm to translate results for the XL probe to those for the M probe. Methods and results Both probes were directly compared first in copolymer phantoms of varying stiffness (4.8, 11, and 40 kPa) and then in 371 obese and nonobese patients (body mass index, range 17.2–72.4) from German (n = 129) and Canadian (n = 242) centers. Liver stiffness values for both probes correlated better in phantoms than in patients (r = 0.98 versus 0.82, P < 0.001). Significantly more patients could be measured successfully using the XL probe than the M probe (98.4% versus 85.2%, respectively, P < 0.001) while the M probe produced a smaller interquartile range (21% versus 32%). Failure of the M probe to measure liver stiffness was not only observed in patients with a high body mass index and long skin-liver capsule distance but also in some nonobese patients (n = 10) due to quenching of the signal from subcutaneous fat tissue. In contrast with the phantoms, the XL probe consistently produced approximately 20% lower liver stiffness values in humans compared with the M probe. A long skin-liver capsule distance and a high degree of steatosis were responsible for this discordance. Adjustment of cutoff values for the XL probe (<5.5, 5.5–7, 7–10, and >10 kPa for F0, F1–2, F3, and F4 fibrosis, respectively) significantly improved agreement between the two probes from r = 0.655 to 0.679. Conclusion Liver stiffness can be measured in significantly more obese and nonobese patients using the XL probe than the M probe. However, the XL probe is less accurate and adjusted cutoff values are required.
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Affiliation(s)
- Esteban Durango
- Department of Medicine and Center for Alcohol Research, Liver Disease and Nutrition, Salem Medical Center, Germany
| | - Christian Dietrich
- Department of Medicine and Center for Alcohol Research, Liver Disease and Nutrition, Salem Medical Center, Germany
| | - Helmut Karl Seitz
- Department of Medicine and Center for Alcohol Research, Liver Disease and Nutrition, Salem Medical Center, Germany
| | - Cornelia Ursula Kunz
- Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany
| | | | | | - Melanie Beaton
- Multi-Organ Transplant Unit, University of Western Ontario, London, Ontario, Canada
| | | | - Robert P Myers
- Liver Unit, Division of Gastroenterology and Hepatology, Department of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Sebastian Mueller
- Department of Medicine and Center for Alcohol Research, Liver Disease and Nutrition, Salem Medical Center, Germany ; Liver Unit, Centre Hospitalier de l'Université de Montréal, Hôpital Saint-Luc, Montréal, Quebec, Canada
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Berenguer M, Schuppan D. Progression of liver fibrosis in post-transplant hepatitis C: mechanisms, assessment and treatment. J Hepatol 2013; 58:1028-41. [PMID: 23262248 DOI: 10.1016/j.jhep.2012.12.014] [Citation(s) in RCA: 118] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 12/10/2012] [Accepted: 12/10/2012] [Indexed: 12/12/2022]
Abstract
Liver fibrosis results from an excessive wound healing response in most chronic liver diseases, such as hepatitis C. Despite great advances in antiviral therapy in recent years, progressive liver fibrosis remains a major problem for patients with recurrent hepatitis C after liver transplantation. Liver biopsy remains a central tool in the management of HCV-positive liver transplant recipients, but reliable non-invasive methods for the assessment of liver fibrosis, such as ultrasound elastography, are increasingly being incorporated in the management of post-transplant patients, helping predict prognosis, guide treatment decisions, and stratify patients for emerging antifibrotic therapies. In this manuscript, we will review the natural history as well as tools to monitor fibrosis progression in the HCV-positive liver transplant recipient, the mechanisms underlying rapid fibrosis progression in up to 30% of these patients, the effect of antiviral therapies and highlight promising antifibrotic approaches.
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Affiliation(s)
- Marina Berenguer
- University Valencia, Dept. of Medicine, Hepatology & Liver Transplantation Unit, La Fe Hospital and CIBEREHD, National Network Center for Hepatology and Gastroenterology Research, Instituto de Salud Carlos III, Spain.
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Karnik GS, Shetty K. Management of recurrent hepatitis C in orthotopic liver transplant recipients. Infect Dis Clin North Am 2013; 27:285-304. [PMID: 23714341 DOI: 10.1016/j.idc.2013.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
End-stage liver disease and hepatocellular carcinoma from chronic hepatitis C are the most common indications for orthotopic liver transplantation and the incidence of both are projected to increase over the next decade. Recurrent hepatitis C virus infection of the allograft is associated with an accelerated progression to cirrhosis, graft loss, and death. This article presents an overview of the natural history of hepatitis C virus recurrence in liver transplant recipients and guidance on optimal management strategies.
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Affiliation(s)
- Geeta S Karnik
- Department of Infectious Diseases, Georgetown University Hospital, Washington, DC 20007, USA.
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Venkatesh SK, Yin M, Ehman RL. Magnetic resonance elastography of liver: technique, analysis, and clinical applications. J Magn Reson Imaging 2013; 37:544-55. [PMID: 23423795 PMCID: PMC3579218 DOI: 10.1002/jmri.23731] [Citation(s) in RCA: 449] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 05/10/2012] [Indexed: 12/12/2022] Open
Abstract
Many pathological processes cause marked changes in the mechanical properties of tissue. MR elastography (MRE) is a noninvasive MRI based technique for quantitatively assessing the mechanical properties of tissues in vivo. MRE is performed by using a vibration source to generate low frequency mechanical waves in tissue, imaging the propagating waves using a phase contrast MRI technique, and then processing the wave information to generate quantitative images showing mechanical properties such as tissue stiffness. Since its first description in 1995, published studies have explored many potential clinical applications including brain, thyroid, lung, heart, breast, and skeletal muscle imaging. However, the best-documented application to emerge has been the use of MRE to assess liver disease. Multiple studies have demonstrated that there is a strong correlation between MRE-measured hepatic stiffness and the stage of fibrosis at histology. The emerging literature indicates that MRE can serve as a safer, less expensive, and potentially more accurate alternative to invasive liver biopsy which is currently the gold standard for diagnosis and staging of liver fibrosis. This review describes the basic principles, technique of performing a liver MRE, analysis and calculation of stiffness, clinical applications, limitations, and potential future applications.
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Affiliation(s)
| | - Meng Yin
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
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Flass T, Narkewicz MR. Cirrhosis and other liver disease in cystic fibrosis. J Cyst Fibros 2013; 12:116-24. [PMID: 23266093 PMCID: PMC3883947 DOI: 10.1016/j.jcf.2012.11.010] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 11/14/2012] [Accepted: 11/15/2012] [Indexed: 12/25/2022]
Affiliation(s)
- Thomas Flass
- Section of Pediatric Gastroenterology, Hepatology and Nutrition, Department of Pediatrics University of Colorado School of Medicine and The Pediatric Liver Center, Children's Hospital Colorado, Aurora, CO, USA
| | - Michael R Narkewicz
- Section of Pediatric Gastroenterology, Hepatology and Nutrition, Department of Pediatrics University of Colorado School of Medicine and The Pediatric Liver Center, Children's Hospital Colorado, Aurora, CO, USA.
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Gonzalez HC, Jafri SM, Gordon SC. Role of liver biopsy in the era of direct-acting antivirals. Curr Gastroenterol Rep 2013; 15:307. [PMID: 23319086 DOI: 10.1007/s11894-012-0307-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
An accurate assessment of the degree of fibrosis or presence of cirrhosis is critical both for the appropriate management of, and to provide prognosis for, patients with chronic hepatitis C infection. In the new era of direct acting antivirals, large numbers of patients may enter therapy, and although liver biopsy remains the gold standard, it is not practical in all settings. In recent years, a variety of noninvasive methods have been developed that may obviate the need for liver biopsy in most settings. Indirect laboratory formulas, tests, panels of biomarkers and imaging modalities may accurately stage the degree of fibrosis in hepatitis C monoinfection, hepatitis C/HIV coinfection, and post-transplant recurrent hepatitis C.
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Abstract
CLINICAL/METHODICAL ISSUE The early detection of liver fibrosis remains a major challenge in medical imaging. STANDARD RADIOLOGICAL METHODS Nowadays staging of liver fibrosis is not a task for radiological examinations and the gold standard is liver puncture. METHODICAL INNOVATIONS Elastography is sensitive to the mechanical properties of soft tissues and in the liver stiffness is highly correlated to the degree of fibrosis. In magnetic resonance imaging elastography (MRE) time-harmonic vibrations are induced in the liver and encoded by motion-sensitive phase-contrast sequences. Viscoelastic constants are recovered from the obtained wave images and displayed by so-called elastograms. PERFORMANCE The MRE procedure is able to discriminate low grades of fibrosis (F0-F1) from medium and severe fibrosis (F2-F4) with a diagnostic accuracy (AUROC) of 0.92. ACHIEVEMENTS Currently, MRE is the most sensitive imaging modality for the noninvasive staging of liver fibrosis. PRACTICAL RECOMMENDATIONS Current technical developments of MRE may further improve the accuracy of the method towards a new gold standard for noninvasive staging of fibrosis by radiologists.
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Affiliation(s)
- I Sack
- Institut für Radiologie, Charité-Universitätsmedizin Berlin, Campus Charité Mitte, Charitéplatz 1, Berlin, Germany.
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Current world literature. Curr Opin Organ Transplant 2013; 18:111-30. [PMID: 23299306 DOI: 10.1097/mot.0b013e32835daf68] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Perumpail RB, Levitsky J, Wang Y, Lee VS, Karp J, Jin N, Yang GY, Bolster BD, Shah S, Zuehlsdorff S, Nemcek AA, Larson AC, Miller FH, Omary RA. MRI-guided biopsy to correlate tissue specimens with MR elastography stiffness readings in liver transplants. Acad Radiol 2012; 19:1121-6. [PMID: 22877987 DOI: 10.1016/j.acra.2012.05.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 03/23/2012] [Accepted: 05/16/2012] [Indexed: 12/11/2022]
Abstract
RATIONALE AND OBJECTIVES Magnetic resonance elastography (MRE) can noninvasively measure the stiffness of liver tissue and display this information in anatomic maps. Magnetic resonance imaging (MRI) guidance has not previously been used to biopsy segments of heterogeneous stiffness identified on MRE. Dedicated study of MRE in post-liver transplant patients is also limited. In this study, the ability of real-time MRI to guide biopsies of segments of the liver with different MRE stiffness values in the same post-transplant patient was assessed. MATERIALS AND METHODS MRE was performed in 9 consecutive posttransplant patients with history of hepatitis C. Segments of highest and lower stiffness on MRE served as targets for subsequent real-time MRI-guided biopsy using T2-weighted imaging. The ability of MRI-guided biopsy to successfully obtain tissue specimens was assessed. The Wilcoxon signed-rank test was used to compare mean stiffness differences for highest and lower MRE stiffness segments, with α = 0.05. RESULTS MRI guidance allowed successful sampling of liver tissue for all (18/18) biopsies. There was a statistically significant difference in mean MRE stiffness values between highest (4.61 ± 1.99 kPa) and lower stiffness (3.03 ± 1.75 kPa) (P = .0039) segments biopsied in the 9 posttransplant patients. CONCLUSION Real-time MRI can guide biopsy in patients after liver transplantation based on MRE stiffness values. This study supports the use of MRI guidance to sample tissue based on functional information.
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Affiliation(s)
- Ryan B Perumpail
- Department of Radiology, Northwestern University, Chicago, IL 60611, USA
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Abstract
As the hepatic manifestation of the metabolic syndrome, nonalcoholic fatty liver disease (NAFLD) has become the most common cause of asymptomatic liver enzyme elevations in Western nations. Although it is easy to diagnose NAFLD, a liver biopsy is currently required to diagnose nonalcoholic steatohepatitis (NASH). Patients with NASH are those at greatest risk of progression to cirrhosis and, thus, treatment efforts are targeted to these individuals. Although currently there are no FDA-approved treatments for NASH, a multidisciplinary approach that addresses comorbid conditions and promotes modest weight loss comprises the backbone of therapy.
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Affiliation(s)
- Angelo H Paredes
- Division of Gastroenterology, Department of Medicine, Walter Reed National Military Medical Center, Bethesda, MD 20889, USA
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48
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Abstract
Hepatitis-C-virus- (HCV-) related end-stage cirrhosis is the primary indication for liver transplantation in many countries. Unfortunately, however, HCV is not eliminated by transplantation and graft reinfection is universal, resulting in fibrosis, cirrhosis, and finally graft decompensation. The use of poor quality organs, particularly from older donors, has a highly negative impact on the severity of recurrence and patient/graft survival. Although immunosuppressive regimens have a considerable impact on the outcome, the optimal regimen after liver transplantation for HCV-infected patients remains unclear. Disease progression monitoring with protocol biopsy and new noninvasive methods is essential for predicting patient/graft outcome and starting antiviral treatment with the appropriate timing. Antiviral treatment with pegylated interferon and ribavirin is currently considered the most promising regimen with a sustained viral response rate of around 30% to 35%, although the survival benefit of this regimen remains to be investigated. Living-donor liver transplantation is now widely accepted as an established treatment for HCV cirrhosis and the results are equivalent to those of deceased donor liver transplantation.
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