Author of 2 Presentations
SS 6.4 - Expert consensus on acquisition and reporting of intestinal US activity in Crohn’s disease: a prospective inter-rater agreement study
Abstract
Purpose
Intestinal US (IUS) is a promising cross-sectional imaging modality used to assess transmural disease and complications in Crohn’s disease (CD). Standard measurements, reproducibility and nomenclature have not yet been clearly established. The aim of this study was to evaluate inter-rater agreement for important parameters by experts through Delphi consensus.
Material and methods
IUS parameters demonstrating inflammatory activity were selected by a blinded Delphi IUS experts consensus panel to establish relative contribution to inflammatory activity in CD. Phase 1: blind review by 8 readers of 20 de-identified CD cases. Cases with poor agreement were reviewed to clarify discrepancy and improve agreement. Phase 2: an additional 30 de-identified CD cases blindly were reviewed by 12 independent expert readers. Inter-rater agreement was evaluated for all 4 key parameters.
Results
The Delphi process reduced 12 activity parameters to 4 key contributors including BWT, color Doppler signal (CDI), inflammatory fat and bowel wall echo stratification. BWT was comprised of 2 measurements in cross section and 2 in longitudinal orientation. Interobserver agreement was almost perfect for BWT: ICC=0.91 (95%CI 0.83-0.96), p=0.001, moderate agreement for CDI, κ=0.60 (95%CI 0.48-0.72), p=0.001. Agreement for inflammatory fat was also moderate with κ=0.50 (95%CI 0.33-0.66), p=0.001, while stratification was fair κ=0.39 (95%CI 0.26-0.53), p=0.001.
Conclusion
This expert consensus-based IUS activity score clearly establishes the reproducibility of this standardized approach to measure inflammatory activity in CD. Using our method, BWT is highly reproducible with CDI and inflammatory fat demonstrating moderate reproducibility. This score may provide the foundation for the future incorporation of IUS in research studies and clinical trials.
Video-on-demand
SS 6.7 - Inter-observer agreement of an expert panel for GIUS in ulcerative colitis
Abstract
Purpose
GIUS is increasingly performed in inflammatory bowel disease to assess disease activity and treatment response. It correlates well with endoscopy and other cross-sectional imaging modalities. However, the reliability of GIUS has poorly been investigated for ulcerative colitis (UC). Therefore, we conducted a study to assess inter-observer agreement in UC.
Material and methods
Thirty patients with UC were included. Cine-loops were recorded for the sigmoid in a longitudinal and cross-sectional axis. Cine-loops were scored by five independent raters blinded for clinical disease activity. The cine-loops were scored for bowel wall thickness (BWT), Doppler activity (0=no signal, 1=small spots limited to the wall, 2=long stretches within the wall, 3=long stretches reaching into the mesenterium), inflammatory fat, bowel wall stratification, loss of haustration and lymph nodes (present or absent). Intraclass correlation coefficient, Fleiss’ kappa and weighted Cohen’s kappa were used for statistical analysis.
Results
Inter-observer agreement was good for bowel wall thickness (ICC: 0.7, 95% CI: 0.51-0.83) and moderate for Doppler signal (k=0.57, 95% CI: 0.37-0.77) and inflammatory fat (k=0.42, 95% CI: 0.29-0.58). When Doppler signal was interpreted as absent (0) or present (1-3), the observed agreement was almost perfect (k=0.81, 95% CI: 0.69-0.92). Agreement was fair for the presence of lymph nodes (k=0.35, 95% CI:0.20-0.49) and loss of stratification (k=0.22 95% CI: 0.09-0.35) and slight for loss of haustrations (k=0.15, 95% CI: 0.00-0.29).
Conclusion
GIUS is a reliable imaging modality with good-to-moderate inter-observer agreement for BWT, vascularization and fatty wrapping in UC. These ultrasonographic parameters are important features to distinguish active from quiescent disease.
Video-on-demand
Author of 2 Presentations
SS 6.4 - Expert consensus on acquisition and reporting of intestinal US activity in Crohn’s disease: a prospective inter-rater agreement study (ID 1084)
Abstract
Purpose
Intestinal US (IUS) is a promising cross-sectional imaging modality used to assess transmural disease and complications in Crohn’s disease (CD). Standard measurements, reproducibility and nomenclature have not yet been clearly established. The aim of this study was to evaluate inter-rater agreement for important parameters by experts through Delphi consensus.
Material and methods
IUS parameters demonstrating inflammatory activity were selected by a blinded Delphi IUS experts consensus panel to establish relative contribution to inflammatory activity in CD. Phase 1: blind review by 8 readers of 20 de-identified CD cases. Cases with poor agreement were reviewed to clarify discrepancy and improve agreement. Phase 2: an additional 30 de-identified CD cases blindly were reviewed by 12 independent expert readers. Inter-rater agreement was evaluated for all 4 key parameters.
Results
The Delphi process reduced 12 activity parameters to 4 key contributors including BWT, color Doppler signal (CDI), inflammatory fat and bowel wall echo stratification. BWT was comprised of 2 measurements in cross section and 2 in longitudinal orientation. Interobserver agreement was almost perfect for BWT: ICC=0.91 (95%CI 0.83-0.96), p=0.001, moderate agreement for CDI, κ=0.60 (95%CI 0.48-0.72), p=0.001. Agreement for inflammatory fat was also moderate with κ=0.50 (95%CI 0.33-0.66), p=0.001, while stratification was fair κ=0.39 (95%CI 0.26-0.53), p=0.001.
Conclusion
This expert consensus-based IUS activity score clearly establishes the reproducibility of this standardized approach to measure inflammatory activity in CD. Using our method, BWT is highly reproducible with CDI and inflammatory fat demonstrating moderate reproducibility. This score may provide the foundation for the future incorporation of IUS in research studies and clinical trials.
Video-on-demand
SS 6.7 - Inter-observer agreement of an expert panel for GIUS in ulcerative colitis (ID 748)
Abstract
Purpose
GIUS is increasingly performed in inflammatory bowel disease to assess disease activity and treatment response. It correlates well with endoscopy and other cross-sectional imaging modalities. However, the reliability of GIUS has poorly been investigated for ulcerative colitis (UC). Therefore, we conducted a study to assess inter-observer agreement in UC.
Material and methods
Thirty patients with UC were included. Cine-loops were recorded for the sigmoid in a longitudinal and cross-sectional axis. Cine-loops were scored by five independent raters blinded for clinical disease activity. The cine-loops were scored for bowel wall thickness (BWT), Doppler activity (0=no signal, 1=small spots limited to the wall, 2=long stretches within the wall, 3=long stretches reaching into the mesenterium), inflammatory fat, bowel wall stratification, loss of haustration and lymph nodes (present or absent). Intraclass correlation coefficient, Fleiss’ kappa and weighted Cohen’s kappa were used for statistical analysis.
Results
Inter-observer agreement was good for bowel wall thickness (ICC: 0.7, 95% CI: 0.51-0.83) and moderate for Doppler signal (k=0.57, 95% CI: 0.37-0.77) and inflammatory fat (k=0.42, 95% CI: 0.29-0.58). When Doppler signal was interpreted as absent (0) or present (1-3), the observed agreement was almost perfect (k=0.81, 95% CI: 0.69-0.92). Agreement was fair for the presence of lymph nodes (k=0.35, 95% CI:0.20-0.49) and loss of stratification (k=0.22 95% CI: 0.09-0.35) and slight for loss of haustrations (k=0.15, 95% CI: 0.00-0.29).
Conclusion
GIUS is a reliable imaging modality with good-to-moderate inter-observer agreement for BWT, vascularization and fatty wrapping in UC. These ultrasonographic parameters are important features to distinguish active from quiescent disease.