Super-resolution ultrasound imaging for in vivo microvasculature assessment in acute kidney injury mouse model

Acute kidney injury (AKI) is a disease with a high mortality rate and increasing incidence. It also generates a high risk of developing into chronic kidney disease (CKD). The deterioration from AKI to CKD is associated with rarefaction of microvasculature in renal cortex. However, there is lack of well-established diagnostic method that can evaluate the microvasculature changes noninvasively and conveniently with a high spatial resolution during the progression from AKI to CKD. Ultrasound super-solution imaging is an emerging technology that can achieve a high spatial resolution of the vasculature beyond the acoustic diffraction limit by localizing the center of the signals from microbubbles. In this study, deconvolution based super-resolution ultrasound imaging is used to noninvasively assess the microvasculature changes in mouse kidney after AKI. Ultrasound scans on mouse kidneys at 3 weeks and 6 weeks post ischemia-reperfusion injury are compared with control mouse kidneys. Obvious microvasculature reduction due to AKI is identified, which is evidenced by histology. The feasibility of ultrasound super-resolution imaging as a potential diagnostic method for progressive renal disease after AKI is demonstrated in the AKI mouse model.