Contrast Enhanced Ultrasound in Human Crohn's Disease-Lumason

Inclusion Criteria: * histologic evidence of small bowel Crohn's disease, or clinical evidence of disease (including radiologic confirmation \[either CT or MRI\] and receiving medical therapy for Crohn's disease). * Between ages 10 and 18 years. * Undergoing clinically-indicated CTE or MRE with evidence of active disease based on pediatric gastroenterologist clinical assessment Exclusion Criteria: * Patients under the age of 10 or over the age of 18. * Pregnancy or breast feeding. Urine pregnancy testing will be performed on all female study participants of reproductive potential. * Obesity/body habitus preventing visualization of small bowel affected by Crohn's disease by ultrasound (Body mass index ≥30 kg/m2 * Subject inability/unwillingness to consent or child assent, including severe developmental delay/mental retardation. * Prior allergic-like reaction or other severe adverse event to Lumason or any of the active ingredients in Lumason (SPECIFIC CONTRAINDICATION from Package Insert). * Known unstable cardiopulmonary conditions (including any history of acute myocardial infarction/acute coronary artery syndrome, arrhythmia, and congestive heart failure), ongoing acute or chronic kidney disease (eGFR \<30 ml/min), moderate/severe chronic lung disease, and end-stage liver disease.