Intestinal ultrasound in Crohn’s disease: A systematic review of its role in diagnosis, monitoring, and treatment response

Table 4 Studies evaluating scoring systems to assess disease activity in inflammatory bowel diseases based on intestinal ultrasound

Ref.	Study type	Follow up	IUS activity	Comparator	Number of patients	Result
Liu et al[60], 2020	Retrospective	8 weeks	UCS	SES-CD	66 CD	UCS > 6 had 92.3% accuracy to identify endoscopically active disease
Allocca et al[64], 2022	Prospective, observational	6 months	BUSS	SES-CD	49 CD	BUSS determined endoscopic response with 80% accuracy and endoscopic remission with 78%
Wang et al[66], 2023	Retrospective	14 months (median)	IBUS-SAS, SUS-CD	SES-CD	140 CD	IBUS-SAS > 48.7 (AUC: 0.895) and SUS-CD > 2.5 (AUC: 0.835) correlated with SES-CD
Kumar et al[67], 2024	Retrospective	6 months	SUS-CD	SES-CD	98 CD	SUS-CD > 3.4 had sensitivity of 82.5% and specificity of 89.2% for active disease
Wang et al[69], 2024	Retrospective	12 weeks	IBUS-SAS	SES-CD	60 pediatric CD	IBUS-SAS showed sensitivity of 87% and specificity of 85% for infliximab response
Xu et al[68], 2023	Prospective	NA	IBUS-SAS	MARIA and SES-CD	100 CD	IBUS-SAS > 47.5 (AUC: 0.91) correlated with MARIA and SES-CD for assessing mucosal activity
Novak et al[59], 2017	Retrospective	NA	SUS-CD	SES-CD, Rutgeerts	160 CD	SUS-CD based on wall thickness and Doppler correlated with endoscopy (AUC: 0.8658)
Ripollés et al[61], 2021	Prospective	NA	Wall thickness, Doppler, and contrast parameters	SES-CD	72 CD	Combined parameters showed AUC: 0.972 for active disease; simpler score AUC: 0.923
Sævik et al[62], 2020	Prospective	NA	Simple ultrasound activity score	SES-CD	40 development, 124 validation	Ultrasound activity index based on wall thickness and Doppler correlated well with SES-CD (AUC: 0.92)

CD: Crohn’s disease; IUS: Intestinal ultrasound; UCS: Ultrasound consolidated score; SES-CD: Simple endoscopic score for Crohn’s disease; BUSS: Bowel ultrasound score; IBUS-SAS: International bowel ultrasound segmental activity score; SUS-CD: Simple ultrasound score for Crohn’s disease; AUC: Area under the curve; FC: Fecal calprotectin; MARIA: Magnetic resonance index of activity.