Intestinal ultrasound as a non-invasive tool to monitor inflammatory bowel disease activity and guide clinical decision making

Table 1 Optimal and limited bowel segments for intestinal ultrasound disease activity monitoring

Optimal bowel segments	Limited bowel segments
Sigmoid colon	Rectum
Descending colon	Splenic flexure
Transverse colon	Proximal ileum
Ascending colon	Jejunum
Ileocecal valve
Terminal ileum

Table 2 Interpretation of validated and simple intestinal ultrasound activity scores for Crohn’s disease and ulcerative colitis

IUS scoring system	BWT (mm)	iFAT	Modified LS	LBWS	Other
Crohn’s disease indices
SUS-CD (0-5)[19]	0: < 3.0		0: LS 0
	1: 3.0-4.9		1: LS 1-2
	2: 5.0-7.9		2: LS 3
	3: ≥ 8.0
Simple US score[20]	0.957 (BWT)		0.859 (LS)
Ulcerative colitis indices
MUC[21,24]	1.4 (BWT)		0: LS 0
			2: LS 1-3
UC-IUS (0-7)[25]	0: ≤ 2	0: Absent	0: LS 0	0: No loss
	1: 2.1-3.0	1: Present	1: LS 1	1: Loss is present
	2: 3.1-4.0		2: LS 2-3
	3: > 4
Civitelli UC index (0-4)[26] (pediatric)	0: ≤ 3		0: LS 0	0: No loss	Abnormal haustrations (0: Normal, 1: Abnormal)
	1: > 3		2: LS 1-3	1: Loss is present

IUS: Intestinal ultrasound; BWT: Bowel wall thickness; iFat: Inflammatory fat; LS: Limberg Score; LBWS: Loss of bowel wall stratification; UC: Ulcerative colitis; CD: Crohn’s disease.