Contrast-enhanced Ultrasound for Detection of Crohn's Disease Activity: Systematic Review and Meta-analysis.
OBJECTIVE
Reports on imaging of active Crohn's disease (aCD) using contrast-enhanced ultrasound (CEUS) are encouraging. However, the statistical power of most published papers is limited due to the small size of the patient groups included. This study was performed to verify the diagnostic value of CEUS in detecting aCD.


METHODS
A systematic literature search was performed by two independent reviewers for articles on the test characteristics of CEUS for the identification of aCD. The quality of the analysed studies was evaluated using a quality assessment tool for diagnostic accuracy studies (QUADAS-2). Pooling was performed using a diagnostic random-effect model and bivariate analysis.


RESULTS
Eight articles were included in the final analysis, with a total of 332 patients. There was no significant publication bias. Significant heterogeneity was found regarding CEUS methodology and sonographic definitions of aCD. In a bivariate analysis, pooled sensitivity was 0.94 (95% CI 0.87-0.97) and pooled specificity was 0.79 (95% CI 0.67-0.88). Spearman correlation statistics presented no significant diagnostic threshold effect (r = 0.12, p > 0.9). Subgroup analysis showed that relative intestine wall enhancement had the highest diagnostic value (area under the curve 94%), while the presence of enhancement and analysis of the slope were less useful (area under the curve 91 and 90%, respectively).


CONCLUSIONS
CEUS presents good sensitivity and moderate specificity in the detection of the aCD. Large-scale randomized trials with quantitative evaluation of CEUS images are necessary to promote this technique in clinical practice.
Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland serafin@cm.umk.pl.
Zbigniew
Z
Serafin
Department of Radiology and Diagnostic Imaging, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland.
Marcin
M
Białecki
Department of Dermatology, Sexually Transmitted Diseases and Immunodermatology, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland.
Agnieszka
A
Białecka
Department of Radiology, IRCCS Policlinico San Donato and Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milano, Italy.
Luca Maria
LM
Sconfienza
Chair of Vascular Diseases and Internal Medicine, Nicolaus Copernicus University, Collegium Medicum, Bydgoszcz, Poland.
Maria
M
Kłopocka
D003287:Contrast Media; D003424:Crohn Disease / Q000000981:diagnostic imaging*; D018450:Disease Progression; D006801:Humans; D045423:Microbubbles; D015233:Models, Statistical; D012680:Sensitivity and Specificity; D014463:Ultrasonography / Q000379:methods*
D003287:Contrast Media
CEUS; Crohn’s disease; meta-analysis