Purpose or Case Report: To review up-to-date imaging techniques, normal sonographic anatomy, and characteristic sonographic features of disorders affecting the gastrointestinal tract in children.
Methods & Materials: We performed a literature review on gastrointestinal ultrasound imaging indications, techniques, and findings in children. We included cases and experience from our institution to summarize diagnostic pearls and pitfalls for pediatric gastrointestinal pathology. We review congenital, acquired, infectious, inflammatory, neoplastic, and vascular disorders, as well as foreign body ingestion.
Results: Ultrasound is an ideal imaging modality in children because it is a real-time, non-invasive, relatively low cost examination without ionizing radiation that requires no sedation. Ultrasound of the bowel is typically a targeted examination, designed to answer a specific question, and common indications include evaluation for appendicitis, intussusception, and pyloric stenosis. Other indications include evaluation of prenatally detected congenital abnormalities, confirmation of suspected hernia, and problem solving in the patient with necrotizing enterocolitis. Unsuspected bowel abnormalities may be found during screening for non-specific abdominal pain, including foreign body, tumor, infection, or bowel hematoma. A more comprehensive examination of the entire bowel can be used to evaluate inflammatory bowel disease and celiac disease in children.
Recent improvements in ultrasound technology, including high-resolution linear probes (12-15 MHz) and harmonic and panoramic imaging, improve image quality. Color Doppler evaluation can detect increased perfusion in inflamed loops of bowel. Ultrasound cine clips document bowel motility, and graded compression assesses compressibility and improves resolution by displacing air from the bowel lumen. Oral administration of non-carbonated fluid 30 minutes prior to the examination will reduce air in the bowel. Small-intestine intravenous contrast enhanced ultrasound and enteric contrast bowel distention are other promising newer techniques for bowel evaluation.
Conclusions: Ultrasound is the often the initial modality detecting abnormalities of the gastrointestinal tract in children, either as part of a targeted examination at the site of symptoms or as an incidental finding. Radiologists interpreting ultrasound examinations in children should be familiar with the sonographic appearance of both the normal and abnormal gastrointestinal tract.