2K-5 Compensation of Attenuation in Contrast-Enhanced Ultrasound: Application to Small Animal Studies

Although perfusion assessment using contrast enhanced ultrasound is of growing interest, accurate quantification of tissue perfusion is still impossible due to the shadowing effect. While many previous methods have been developed for attenuation correction in soft tissues, we propose a model to estimate attenuation caused by contrast agent microbubbles, using the time-intensity variation in a highly echogenic distal area without contrast uptake. This model, based on the assumption that a particular relationship holds between local attenuation and backscatter, is applied to a murine renal perfusion study. Parametric images of attenuation and backscatter are provided. Shadowing artefacts are correctly separated from backscatter, so that contrast uptake kinetics consistent with the physiology are retrieved in all perfused areas, even in the distal kidney. Moreover, comparable values of attenuation are found in both cortices. These preliminary results suggest that this method makes it possible to independently estimate attenuation and backscatter due to contrast agent microbubbles