  Purpose: As a typical chronic kidney disease (CKD), hypertensive
nephrosclerosis (HN) is a common syndrome of hypertension, characterized by
chronic kidney microvascular damage. Early diagnosis of microvascular damage
using conventional ultrasound imaging encounters challenges in sensitivity and
specificity owing to the inherent diffraction limit. Ultrasound localization
microscopy (ULM) has been developed to obtain microvasculature and
microvascular hemodynamics within the kidney, and would be a promising tool for
early diagnosis of CKD.
  Methods: In this study, the advantage of ULM over conventional clinical
inspection (serum and urine tests) and ultrasound imaging (Doppler and
contrast-enhanced ultrasound imaging) for early diagnosis of HN was
investigated. Examinations were carried out on 6 spontaneously hypertensive
rats (SHR) and 5 normal Wistar-Kyoto (WKY) rats at the age of 10 weeks.
  Results: The experimental results showed that the indicators derived from
conventional clinical inspection and ultrasound imaging (PSV, EDV, RI, RT,
IMAX, mTT and AUC) did not show significant difference between hypertensive and
healthy rats (p > 0.05), while the TTP derived from CEUS (p < 0.05) and the
mean blood flow speed in artery of SHR derived from ULM is significantly higher
than that of WKY rats (p < 0.01).
  Conclusion: The quantitative results showed that ULM has higher sensitivity
than conventional clinical inspection and ultrasound imaging. ULM may promise a
reliable solution for early diagnosis of HN.
