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Rimola J, Fernandez-Clotet A, Capozzi N, Caballol B, Rodríguez S, Gallego M, Masamunt MC, Panés J, Ricart E, Ordás I. ADC Values for Detecting Bowel Inflammation and Biologic Therapy Response in Patients With Crohn Disease: A Post Hoc Prospective Trial Analysis. AJR Am J Roentgenol 2024; 222:e2329639. [PMID: 37584507 DOI: 10.2214/ajr.23.29639] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
BACKGROUND. New biologic agents for Crohn disease (CD) create a need for noninvasive disease markers. DWI may assess bowel inflammation without contrast agents. OBJECTIVE. The purpose of this study was to evaluate ADC values for identifying bowel inflammation and therapeutic response in patients with CD treated with biologic therapy. METHODS. This study entailed post hoc analysis of prospective trial data. Analysis included 89 patients (median age, 37 years; 49 women, 40 men) with CD treated by biologic therapy who underwent MR enterography (MRE) at baseline and 46 weeks after therapy, from March 2013 to April 2021; 43 patients underwent ileocolonoscopy at both time points. Analysis was conducted at the level of small-bowel and colorectal segments (586 segments analyzed). MR index of activity (MaRIA) score and presence of endoscopic ulcers were determined at both time points. One observer measured bowel wall ADC. Diagnostic performance was evaluated. Dichotomous ADC assessments used a threshold of 1301 × 10-6 mm2/s based on initial ROC analysis; dichotomous MaRIA score assessments used a threshold of 11 (moderate to severe inflammation). A second observer repeated ADC measurements in 15 patients. RESULTS. At baseline, ADC had AUC of 0.92, sensitivity of 78.6%, specificity of 91.4%, and accuracy of 88.2% for detecting segments with MaRIA score 11 or greater. At baseline, AUC for detecting endoscopic ulcers was 0.96 for MaRIA score versus 0.87 for ADC (p < .001); sensitivity, specificity, and accuracy were 70.8%, 90.2%, and 85.1% for ADC and 86.2%, 96.2%, and 93.6% for MaRIA score. At follow-up, ADC had AUC of 0.87, sensitivity of 75.4%, specificity of 83.6%, and accuracy of 80.0% for detecting improvement in MaRIA score to less than 11. At follow-up, AUC for detecting endoscopic ulcer healing was 0.94 for MaRIA score versus 0.84 for ADC (p = .01); sensitivity, specificity, and accuracy were 70.7%, 95.8%, and 84.4% for ADC and 90.2%, 100.0%, and 95.6% for MaRIA score. Interobserver agreement for ADC, based on intraclass correlation coefficient, was 0.70 at baseline and 0.65 at follow-up. CONCLUSION. The findings do not support use of ADC rather than MaRIA scores for detecting biologic therapy response. CLINICAL IMPACT. ADC may have an adjunct role in assessing bowel inflammation in CD, but showed limited performance for detecting biologic therapy response.
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Affiliation(s)
- Jordi Rimola
- Radiology Department, IBD Unit, Hospital Clínic de Barcelona, Villarroel 170, Escala 3 Planta 1, 08036, Barcelona, Spain
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | | | - Nunzia Capozzi
- Radiology Department, IBD Unit, Hospital Clínic de Barcelona, Villarroel 170, Escala 3 Planta 1, 08036, Barcelona, Spain
- Radiology Department, Policlinico Universitario Sant'Orsola-Malpighi, Bologna, Italy
| | - Berta Caballol
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Sonia Rodríguez
- Gastroenterology Department, IBD Unit, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Marta Gallego
- Gastroenterology Department, IBD Unit, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Maria Carme Masamunt
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Gastroenterology Department, IBD Unit, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Julian Panés
- Gastroenterology Department, IBD Unit, Hospital Clínic de Barcelona, Barcelona, Spain
| | - Elena Ricart
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Gastroenterology Department, IBD Unit, Hospital Clínic de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain
- University of Barcelona, Barcelona, Spain
| | - Ingrid Ordás
- Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Gastroenterology Department, IBD Unit, Hospital Clínic de Barcelona, Barcelona, Spain
- Centro de Investigación Biomédica en Red Enfermedades Hepáticas y Digestivas (CIBERehd), Barcelona, Spain
- University of Barcelona, Barcelona, Spain
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Gladkikh M, Benchimol EI, Mack DR, Mojaverian N, Highmore K, Miller E, Davila J. MR Enterography Scores Correlate with Degree of Mucosal Healing in Pediatric Crohn's Disease: A Pilot Study. J Can Assoc Gastroenterol 2023; 6:125-130. [PMID: 37273972 PMCID: PMC10235592 DOI: 10.1093/jcag/gwad010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/06/2023] Open
Abstract
Objectives MR enterography (MRE) Index of Activity (MaRIA) and Clermont are validated scores that correlate with Crohn's disease (CD) activity; however, the Clermont score has not been validated to correlate with the degree of change in mucosal inflammation post induction treatment in children. This pilot study evaluated if MaRIA and Clermont scores can serve as surrogates to ileocolonoscopy for assessing interval change in mucosal inflammation in pediatric CD post-induction treatment. Methods Children with known or newly diagnosed ileocolonic CD starting or changing therapy underwent ileocolonoscopy, scored with simple endoscopic score for Crohn's disease (SES-CD), and MRE on the same day at two time points (Week 0 and 12). Accuracy of global MaRIA and Clermont indices relative to ileocolonoscopy in detecting degree of post-treatment interval change in mucosal inflammation was assessed through correlational coefficients (r). Inter-reader agreement was calculated for imaging scores through intraclass correlation (ICC). Results Sixteen children (mean age 11.5 ± 2.8) were evaluated. Global MaRIA/Clermont correlated with SES-CD in detecting the degree of change in mucosal inflammation (r = 0.676 and r = 0.677, P < 0.005, respectively). Correlation for pooled timepoint assessments between SES-CD and global MaRIA/Clermont was moderate (r = 0.546, P < 0.001 and r = 0.582, P < 0.001, respectively). Inter-rater reliability for global MaRIA and Clermont was good (ICC = 0.809 and ICC = 0.768, respectively, P < 0.001). Conclusions MRE-based global scores correlate with endoscopic indices and may be used to monitor disease changes in children with CD undergoing induction treatment, which can advise the physician if treatment changes should be made.
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Affiliation(s)
- Maria Gladkikh
- Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Department of Medical Imaging, McMaster University, Hamilton, Ontario, Canada
| | - Eric I Benchimol
- SickKids Inflammatory Bowel Disease Centre, Division of Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Paediatrics and Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada
- Child Health Evaluative Sciences, SickKids Research Institute, Toronto, Ontario, Canada
| | - David R Mack
- Division of Gastroenterology, Hepatology and Nutrition, Children’s Hospital of Eastern Ontario (CHEO), Ottawa, Ontario, Canada
- Department of Pediatrics, University of Ottawa, Ottawa, Ontario, Canada
| | - Nassim Mojaverian
- Institute for Clinical Evaluative Sciences, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Kerri Highmore
- Department of Medical Imaging, CHEO, Ottawa, Ontario, Canada
- Faculty of Medicine, Department of Radiology, University of Ottawa, Ottawa, Ontario, Canada
| | - Elka Miller
- Department of Medical Imaging, CHEO, Ottawa, Ontario, Canada
- Faculty of Medicine, Department of Radiology, University of Ottawa, Ottawa, Ontario, Canada
| | - Jorge Davila
- Correspondence: Jorge Davila, MD, FRCPC, Department of Medical Imaging, CHEO, 401 Smyth Road, Ottawa, Ontario K1H 8L1, Canada, e-mail:
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Replacing Endoscopy with Magnetic Resonance Enterography for Mucosal Activity Assessment in Terminal Ileal Crohn’s Disease: Are We There Yet? Diagnostics (Basel) 2023; 13:diagnostics13061061. [PMID: 36980368 PMCID: PMC10046927 DOI: 10.3390/diagnostics13061061] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 02/28/2023] [Accepted: 03/07/2023] [Indexed: 03/18/2023] Open
Abstract
Crohn’s disease (CD) is a chronic immune mediated disorder that most commonly affects the small bowel and/or the large bowel. Treatment targets in CD include mucosal healing assessed via ileocolonoscopy and transmural healing assessed through cross-sectional imaging modalities such as magnetic resonance enterography (MRE). More recently, histological healing in CD has emerged as a treatment target, though it is made cumbersome given its reliance on frequent endoscopic examinations. With expert guidelines now recommending regular objective assessments as part of a treat-to-target approach, accurate non-invasive assessment will become increasingly critical. MRE has an established role in the assessment of small bowel CD, with growing data supportive of its ability in detecting disease activity at mucosal and histological levels. This could therefore potentially reduce the need for serial endoscopic assessment. Thus, this review will assess the capacity of individual MRE parameters and MRE indices for detecting mucosal and histological small bowel CD activity. Furthermore, challenging scenarios, such as CD activity detection in post-operative clinical scenarios and abnormal findings in the context of a normal ileocolonoscopy, will be explored.
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Javaid A, Shahab O, Adorno W, Fernandes P, May E, Syed S. Machine Learning Predictive Outcomes Modeling in Inflammatory Bowel Diseases. Inflamm Bowel Dis 2021; 28:819-829. [PMID: 34417815 PMCID: PMC9165557 DOI: 10.1093/ibd/izab187] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Indexed: 12/14/2022]
Abstract
There is a rising interest in use of big data approaches to personalize treatment of inflammatory bowel diseases (IBDs) and to predict and prevent outcomes such as disease flares and therapeutic nonresponse. Machine learning (ML) provides an avenue to identify and quantify features across vast quantities of data to produce novel insights in disease management. In this review, we cover current approaches in ML-driven predictive outcomes modeling for IBD and relate how advances in other fields of medicine may be applied to improve future IBD predictive models. Numerous studies have incorporated clinical, laboratory, or omics data to predict significant outcomes in IBD, including hospitalizations, outpatient corticosteroid use, biologic response, and refractory disease after colectomy, among others, with considerable health care dollars saved as a result. Encouraging results in other fields of medicine support efforts to use ML image analysis-including analysis of histopathology, endoscopy, and radiology-to further advance outcome predictions in IBD. Though obstacles to clinical implementation include technical barriers, bias within data sets, and incongruence between limited data sets preventing model validation in larger cohorts, ML-predictive analytics have the potential to transform the clinical management of IBD. Future directions include the development of models that synthesize all aforementioned approaches to produce more robust predictive metrics.
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Affiliation(s)
- Aamir Javaid
- Division of Pediatric Gastroenterology and Hepatology, Department of Pediatrics, University of Virginia, Charlottesville, VA, USA
| | - Omer Shahab
- Division of Gastroenterology and Hepatology, Department of Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - William Adorno
- School of Data Science, University of Virginia, Charlottesville, VA, USA
| | - Philip Fernandes
- Division of Pediatric Gastroenterology and Hepatology, Department of Pediatrics, University of Virginia, Charlottesville, VA, USA
| | - Eve May
- Division of Gastroenterology and Hepatology, Department of Pediatrics, Children’s National Hospital, Washington, DC, USA
| | - Sana Syed
- Division of Pediatric Gastroenterology and Hepatology, Department of Pediatrics, University of Virginia, Charlottesville, VA, USA,School of Data Science, University of Virginia, Charlottesville, VA, USA,Address Correspondence to: Sana Syed, MD, MSCR, MSDS, Division of Pediatric Gastroenterology and Hepatology, Department of Pediatrics, University of Virginia, 409 Lane Rd, Room 2035B, Charlottesville, VA, 22908, USA ()
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Bufman H, Eliakim R, Tau N, Amitai MM. Magnetic resonance enterography in Crohn's disease patients: current state of the art and future perspectives. Expert Rev Med Devices 2021; 18:657-667. [PMID: 34109891 DOI: 10.1080/17434440.2021.1939682] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION Crohn's disease (CD) is a major concern due to relatively high incidence and major complications like stricture or fistulas, often requiring surgical treatment. In recent years, magnetic resonance enterography (MRE) became a popular method of diagnosis and disease surveillance. The purpose of this review is to summarize and discuss the major and most recent advances in various aspects of MRE usage in diagnosong Crohn's disease, and to discuss advances in technique, disease activity monitoring and response to treatment. METHODS A literature search was performed and relevant publications were included, with emphasis on articles from the past decade. AREAS COVERED In this review we have presented articles with major advances in the field of MRE of CD patients such as proper sequence selection, recent advances in scoring of disease activity, differentiation between inflammation and fibrosis, response to treatment and technological advances such as the use of AI. EXPERT OPINION The main goal in improving MRE performance will be sequence selection aimed at differenting between inflammation and stricture while shortening the study length adjusted to patient compliance, and developing a standardized scoring system for MRE reporting assisted by artificial intelligence.
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Affiliation(s)
- Hila Bufman
- Department of Diagnostic Imaging, Sheba Medical Center, Tel Hashomer, Israel.,Sackler School of Medicine, Tel Aviv University, Tel-Aviv, Israel
| | - Rami Eliakim
- Sackler School of Medicine, Tel Aviv University, Tel-Aviv, Israel.,Department of Gastroenterology, Sheba Medical Center, Tel Hashomer, Israel
| | - Noam Tau
- Department of Diagnostic Imaging, Sheba Medical Center, Tel Hashomer, Israel.,Sackler School of Medicine, Tel Aviv University, Tel-Aviv, Israel
| | - Michal Marianne Amitai
- Department of Diagnostic Imaging, Sheba Medical Center, Tel Hashomer, Israel.,Sackler School of Medicine, Tel Aviv University, Tel-Aviv, Israel
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Chang HC, Chen G, Chung HW, Wu PY, Liang L, Juan CJ, Liu YJ, Tse MLD, Chan A, Zhang S, Chiu KWH. Multi-shot Diffusion-Weighted MRI With Multiplexed Sensitivity Encoding (MUSE) in the Assessment of Active Inflammation in Crohn's Disease. J Magn Reson Imaging 2021; 55:126-137. [PMID: 34169600 DOI: 10.1002/jmri.27801] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 06/11/2021] [Accepted: 06/11/2021] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Single-shot diffusion-weighted imaging (ssDWI) has been shown useful for detecting active bowel inflammation in Crohn's disease (CD) without MRI contrast. However, ssDWI suffers from geometric distortion and low spatial resolution. PURPOSE To compare conventional ssDWI with higher-resolution ssDWI (HR-ssDWI) and multi-shot DWI based on multiplexed sensitivity encoding (MUSE-DWI) for evaluating bowel inflammation in CD, using contrast-enhanced MR imaging (CE-MRI) as the reference standard. STUDY TYPE Prospective. SUBJECTS Eighty nine patients with histological diagnosis of CD from previous endoscopy (55 male/34 female, age: 17-69 years). FIELD STRENGTH/SEQUENCES: ssDWI (2.7 mm × 2.7 mm), HR-ssDWI (1.8 mm × 1.8 mm), MUSE-DWI (1.8 mm × 1.8 mm) based on echo-planar imaging, T2-weighted imaging, and CE-MRI sequences, all at 1.5 T. ASSESSMENT Five raters independently evaluated the tissue texture conspicuity, geometry accuracy, minimization of artifacts, diagnostic confidence, and overall image quality using 5-point Likert scales. The diagnostic performance (sensitivity, specificity and accuracy) of each DWI sequences was assessed on per-bowel-segment basis. STATISTICAL TESTS Inter-rater agreement for qualitative evaluation of each parameter was measured by the intra-class correlation coefficient (ICC). Paired Wilcoxon signed-rank tests were performed to evaluate the statistical significance of differences in qualitative scoring between DWI sequences. A P value <0.05 was considered to be statistically significant. RESULTS Tissue texture conspicuity, geometric distortions, and overall image quality were significantly better for MUSE-DWI than for ssDWI and HR-ssDWI with good agreement among five raters (ICC: 0.70-0.89). HR-ssDWI showed significantly poorer performance to ssDWI and MUSE-DWI for all qualitative scores and had the worst diagnostic performance (sensitivity of 57.0% and accuracy of 87.3%, with 36 undiagnosable cases due to severe artifacts). MUSE-DWI showed significantly higher sensitivity (97.5% vs. 86.1%) and accuracy (98.9% vs. 95.1%) than ssDWI for detecting bowel inflammation. DATA CONCLUSION MUSE-DWI was advantageous in assessing bowel inflammation in CD, resulting in improved spatial resolution and image quality. LEVEL OF EVIDENCE 2 TECHNICAL EFFICACY STAGE: 2.
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Affiliation(s)
- Hing-Chiu Chang
- Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong
| | - Guangtao Chen
- Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong
| | - Hsiao-Wen Chung
- Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan
| | - Philip Yuguang Wu
- Department of Clinical Oncology, Pamela Youde Nethersole Eastern Hospital, Chai Wan, Hong Kong
| | - Liyuan Liang
- Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong
| | - Chun-Jung Juan
- Department of Medical Imaging, Chinese Medical University Hsinchu Hospital, Hsinchu, Taiwan.,Department of Radiology, School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan.,Department of Medical Imaging, Chinese Medical University Hospital, Taichung, Taiwan
| | - Yi-Jui Liu
- Department of Automatic Control Engineering, Feng Chia University, Taichung, Taiwan
| | | | - Arren Chan
- Department of Radiology, Queen Mary Hospital, Pokfulam, Hong Kong
| | - Sailong Zhang
- Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong
| | - Keith Wan-Hang Chiu
- Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong
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Abstract
ABSTRACT In this review article, we present the latest developments in quantitative imaging biomarkers based on magnetic resonance imaging (MRI), applied to the diagnosis, assessment of response to therapy, and assessment of prognosis of Crohn disease. We also discuss the biomarkers' limitations and future prospects. We performed a literature search of clinical and translational research in Crohn disease using diffusion-weighted MRI (DWI-MRI), dynamic contrast-enhanced MRI (DCE-MRI), motility MRI, and magnetization transfer MRI, as well as emerging topics such as T1 mapping, radiomics, and artificial intelligence. These techniques are integrated in and combined with qualitative image assessment of magnetic resonance enterography (MRE) examinations. Quantitative MRI biomarkers add value to MRE qualitative assessment, achieving substantial diagnostic performance (area under receiver-operating curve = 0.8-0.95). The studies reviewed show that the combination of multiple MRI sequences in a multiparametric quantitative fashion provides rich information that may help for better diagnosis, assessment of severity, prognostication, and assessment of response to biological treatment. However, the addition of quantitative sequences to MRE examinations has potential drawbacks, including increased scan time and the need for further validation before being used in therapeutic drug trials as well as the clinic.
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Wilkens R, Novak KL, Maaser C, Panaccione R, Kucharzik T. Relevance of monitoring transmural disease activity in patients with Crohn's disease: current status and future perspectives. Therap Adv Gastroenterol 2021; 14:17562848211006672. [PMID: 33948115 PMCID: PMC8053830 DOI: 10.1177/17562848211006672] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 03/11/2021] [Indexed: 02/04/2023] Open
Abstract
Treatment targets of inflammatory bowel diseases (IBD), ulcerative colitis (UC) and Crohn's disease (CD) have evolved over the last decade. Goals of therapy consisting of symptom control and steroid sparing have shifted to control of disease activity with endoscopic remission being an important endpoint. Unfortunately, this requires ileocolonoscopy, an invasive procedure. Biomarkers [C-reactive protein (CRP) and fecal calprotectin (FCP)] have emerged as surrogates for endoscopic remission and disease activity, but also have limitations. Despite this evolution, we must not lose sight that CD involves transmural inflammation, not fully appreciated with ileocolonoscopy. Therefore, transmural assessment of disease activity by cross-sectional imaging, in particular with magnetic resonance enterography (MRE) and intestinal ultrasonography (IUS), is vital to fully understand disease control. Bowel-wall thickness (BWT) is the cornerstone in assessment of transmural inflammation and BWT normalization, with or without bloodflow normalization, the key element demonstrating resolution of transmural inflammation, namely transmural healing (TH) or transmural remission (TR). In small studies, achievement of TR has been associated with improved long-term clinical outcomes, including reduced hospitalization, surgery, escalation of treatment, and a decrease in clinical relapse over endoscopic remission alone. This review will focus on the existing literature investigating the concept of TR or residual transmural disease and its relation to other existing treatment targets. Current data suggest that TR may be the next logical step in the evolution of treatment targets.
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Affiliation(s)
- Rune Wilkens
- Gastrounit, Division of Medicine, Copenhagen University Hospital Hvidovre, Hvidovre, Copenhagen, Denmark
- Copenhagen Center for Inflammatory Bowel Disease in Children, Adolescents and Adults, University of Copenhagen, Hvidovre Hospital, Denmark
| | - Kerri L. Novak
- Division of Gastroenterology and Hepatology, University of Calgary, Calgary, AB, Canada
| | - Christian Maaser
- Inflammatory Bowel Disease Outpatient Unit, Department of Geriatric Medicine, University Teaching Hospital Lueneburg, Lueneburg, Germany
| | - Remo Panaccione
- Inflammatory Bowel Disease Unit, Division of Gastroenterology and Hepatology, University of Calgary, Calgary, AB, Canada
| | - Torsten Kucharzik
- Department of Gastroenterology, University Teaching Hospital Lueneburg, Bögelstraße 1, Lueneburg 21339, Germany
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