Objective To explore the application value of micro flow imaging (MFI) combined with contrast-enhanced ultrasound (CEUS) in the diagnosis and localization of active bleeding from renal trauma. Methods The model of renal trauma with active bleeding was established in 10 healthy Bama miniature pigs. B-mode ultrasound

color Doppler flow imaging

CEUS and MFI combined with CEUS were performed successively after the model was established. The accuracy of CEUS and MFI combined with CEUS in the diagnosis and localization of active bleeding from renal trauma were compared. The inner diameter of damaged vessels in renal trauma with active bleeding was measured on MFI combined with CEUS images. Results 18 cases of renal trauma with active bleeding were successfully established in Bama miniature pigs. The accuracy of CEUS and MFI combined CEUS in the diagnosing of active bleeding was 77.78% and 94.44%

respectively

and the difference was not statistically significant (P>0.05). The accuracy of CEUS and MFI combined CEUS in the localization of active bleeding was 55.56% and 94.44%

respectively

and the difference was statistically significant (P<0.05). The inner diameter of damaged vessels in renal trauma with active bleeding on MFI combined with CEUS images was 1.54-2.42 mm. Conclusion MFI combined with CEUS can clearly display the damaged vessels of renal trauma with active bleeding

accurately diagnose active bleeding

and improve the ability to locate active bleeding

providing more diagnostic information for guiding clinical minimally invasive interventional hemostasis and prognosis evaluation.