Endocrine Abstracts

About one in six hospital admissions are for a primary diagnosis of gastrointestinal (GI) disease in the UK, according to the British Society of Gastroenterology, and there is a similar incidence of disease in other developed countries. Inflammatory disease of the gut, in particular, alters the release of cytokines and gut hormones. Medication is used to manage GI diseases and endoscopies help visually monitor its progression. However, this procedure is invasive and causes distress to patients. Contrast enhanced ultrasound (CEUS) imaging is a non-invasive technique using microbubbles filled with gas as a contrast agent. In this work, CEUS imaging was used to study the effect of GI inflammation in mice. Developing such a protocol is a critical step towards using CEUS as a tool in GI disease research. Imaging them non-invasively would allow the field’s understanding of gut function in health and disease to significantly progress. For this work, mice were anaesthetised and imaged with a Verasonics high frequency L22-14Vx probe. A volume of 50µl of microbubbles was injected intravenously at a concentration of 1 billion microbubbles/ml. After the data was acquired, the tissue signal was removed using singular value decomposition; ultrasound localisation microscopy was then applied to the remaining blood and bubble signal. This processing chain allowed individual bubbles to be localised and tracked allowing blood flow through individual villi to be visualised. These images allow structural metrics such as villi length and density to be collected; while dynamic information regarding the direction and rate of blood flow can also be calculated, providing detailed information on gut physiology and pathophysiology. This data demonstrates the potential of CEUS to investigate gut disease. Future work will longitudinally monitor gut pathology using CEUS and link this to cytokine and gut hormone profiles to better understand gut disease and treatment response.