US may be a suitable alternative for evaluation of the terminal ileum in younger children who would otherwise require sedation for MRE or CTE examinations [21]. Sonographic technique requires a systematic assessment of the entire bowel including terminal ileum, colon, and more proximal small bowel. All four quadrants of the abdomen should be evaluated in both the transverse and longitudinal planes [32]. Color Doppler US is also performed to facilitate mural hyperemia assessment. Sonographic features include abnormal bowel wall thickening (>3 mm in children), alteration of bowel wall signature, adjacent fatty proliferation, hyperemia, and engorgement of the vasa recta [32]. Patient features may adversely affect US including elevated body mass index as well as bowel gas resulting in shadowing. In the setting of pediatric Crohn disease, though, obesity is less likely given that many patients have impaired nutrition [32]. The detection of alternative diagnoses is also decreased compared with CT or MRI. US Abdomen With IV Contrast Currently, there is a lack of studies to support using CEUS in children in the acute or emergent setting. WBC Scan Whole Body Tc-99m HMPAO WBC scan has very significant practical limitations in the acute setting. One disadvantage is the decreased ability to detect and evaluate alternative diagnoses. Other significant disadvantages are the technical aspects including volume of blood required for labeling and longer acquisition times limiting usage in this variant. Crohn Disease-Child CTE provides high diagnostic performance for evaluation of Crohn disease activity in pediatric patients, as in adults, with a sensitivity >80% and a specificity >85% compared with endoscopic and histologic reference [11-13]. These studies directly compared CTE and MRE and did not find any significant difference in performance between the two modalities.
Crohn Disease Child. US may be a suitable alternative for evaluation of the terminal ileum in younger children who would otherwise require sedation for MRE or CTE examinations [21]. Sonographic technique requires a systematic assessment of the entire bowel including terminal ileum, colon, and more proximal small bowel. All four quadrants of the abdomen should be evaluated in both the transverse and longitudinal planes [32]. Color Doppler US is also performed to facilitate mural hyperemia assessment. Sonographic features include abnormal bowel wall thickening (>3 mm in children), alteration of bowel wall signature, adjacent fatty proliferation, hyperemia, and engorgement of the vasa recta [32]. Patient features may adversely affect US including elevated body mass index as well as bowel gas resulting in shadowing. In the setting of pediatric Crohn disease, though, obesity is less likely given that many patients have impaired nutrition [32]. The detection of alternative diagnoses is also decreased compared with CT or MRI. US Abdomen With IV Contrast Currently, there is a lack of studies to support using CEUS in children in the acute or emergent setting. WBC Scan Whole Body Tc-99m HMPAO WBC scan has very significant practical limitations in the acute setting. One disadvantage is the decreased ability to detect and evaluate alternative diagnoses. Other significant disadvantages are the technical aspects including volume of blood required for labeling and longer acquisition times limiting usage in this variant. Crohn Disease-Child CTE provides high diagnostic performance for evaluation of Crohn disease activity in pediatric patients, as in adults, with a sensitivity >80% and a specificity >85% compared with endoscopic and histologic reference [11-13]. These studies directly compared CTE and MRE and did not find any significant difference in performance between the two modalities.