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

Table 2 Studies summarizing utility of contrast-enhanced ultrasound in Crohn’s disease activity assessment

Ref.	Study type	Number of patients	Utility of CEUS in CD
Sidhu et al[50], 2023	Retrospective	25 pediatric	CEUS with shear wave elastography differentiated inflammatory from fibrotic strictures, correlating with histopathology
Wang et al[36], 2024	Retrospective	52	CEUS detected active inflammation using dynamic perfusion parameters with high sensitivity (97.4%) and specificity (100%)
Cheng et al[33], 2016	Retrospective	77	CEUS quantified intestinal wall perfusion and identified influencing factors like depth, pressure, and intraluminal gas
Giangregorio et al[29], 2009	Prospective	30	CEUS predicted clinical activity and follow-up outcomes using time-intensity curves and vascularization analysis
Girlich et al[30], 2009	Retrospective	20 CD, 4 controls	Quantified bowel wall vascularity and inflammation with CEUS, showing significant differences compared to controls
Horjus Talabur Horje et al[32], 2015	Prospective	105	CEUS matched MRE accuracy (99%) for active ileitis, with high sensitivity (100%) and specificity (92%)
Kratzer et al[28], 2005	Prospective	21	CEUS quantified vascularity and differentiated active from inactive CD and other complications like abscesses
Laterza et al[102], 2020	Prospective	54	CEUS perfusion parameters predicted response to anti-TNF therapy and identified patients at risk of clinical relapse
Białecki et al[34], 2014	Prospective	42	CEUS correlated with endoscopic activity and fecal calprotectin. Higher vascularity and peak enhancement indicated active CD
Ding et al[149], 2022	Prospective	76	CEUS showed similar diagnostic accuracy to CTE for active inflammation. CEUS was better at detecting mural vascularization
Guidi et al[113], 2006	Prospective	25	CEUS predicted response to infliximab in active CD by assessing vascularization and bowel wall enhancement
Malagò et al[47], 2012	Prospective	30	CEUS findings showed good correlation with MRI in lesion length, wall thickness, and inflammatory activity assessment
Nylund et al[44], 2013	Retrospective	37	Quantitative CEUS differentiated inflammatory from fibrotic strictures based on blood flow and volume
Paredes et al[45], 2013	Prospective	60	CEUS demonstrated high accuracy (98.3%) for postoperative recurrence in CD, correlating well with endoscopy
Pauls et al[46], 2006	Prospective	21	CEUS and MRI were comparable in evaluating vascularity and bowel wall inflammation in active CD
Ponorac et al[48], 2023	Prospective	36 pediatric	CEUS showed high specificity (100%) for assessing pediatric CD activity, correlating well with endoscopy and PCDAI scores
Ripollés et al[93], 2013	Retrospective	50	CEUS differentiated phlegmon from abscess with 100% specificity, aiding in treatment planning for CD complications
Ripollés et al[31], 2013	Prospective	25	CEUS differentiated inflammatory from fibrostenotic lesions with good correlation to histopathology, aiding in therapy decisions
Mao et al[49], 2018	Prospective	31	CEUS detected fistulous tracts associated with abscesses, with high sensitivity (86.7%) and specificity (100%), improving diagnostic precision
Schirin-Sokhan et al[42], 2011	Prospective	18	CEUS demonstrated partial agreement with CDS and was superior for therapy response assessment in active CD
Wilkens et al[38], 2018	Retrospective	50	High peak CEUS enhancement with minimal decline suggested severe CD due to prolonged microbubble retention in inflamed bowel walls
Wilkens et al[87], 2018	Prospective	20	CEUS and dynamic CE-MRE provided complementary insights into stricture stiffness, with CEUS emphasizing inflammatory characteristics

CD: Crohn’s disease; CEUS: Contrast-enhanced ultrasound; CDS: Colour doppler signal; MRI: Magnetic resonance imaging; MRE: Magnetic resonance enterography; TNF: Tumor necrosis factor; PCDAI: Pediatric Crohn’s Disease Activity Index.