Contrast enhanced ultrasonography of kidney in conscious and anesthetized beagle dogs

Contrast enhanced ultrasound (CEUS) is useful to evaluate tissue perfusion in the kidney. In veterinarymedicine, sedation or anesthesia may be required in uncooperative or panting patients. The aim of this studywas to evaluate and compare the normal kidney perfusion patterns in conscious and anesthetized dogs usingCEUS. Eight healthy beagles were used in this study. Scanning was performed in conscious dogs using manualrestraint (conscious group), or under general anesthesia using tiletamine-zolazepam and medetomidine (TZMgroup) or medetomidine (M group). The contrast agent (Sonovue^®) was administered as an IV bolus.The peak intensity (PI), time to peak enhancement from injection (TTP₀) and the time to peakenhancement from the initial rise (TTP_up), upslope, downslope and area under the curve (AUC) wereanalyzed. Compared to the cortical values in the conscious group, TTP₀ was significantly delayed inthe TZM group, and upslope, TTP₀ and TTP_up were significantly different in the M group.The AUCs in the TZM and M groups were not different from those in the conscious group. The upslope of renalmedullary perfusion was significantly decreased in the TZM and M groups. TTP₀ and TTP_upwere also significantly delayed in these groups. The AUC of the medulla was significantly decreased in the Mgroup. Therefore, TZM is useful as an anesthetic protocol when performing CEUS, and the obtained data mayserve as reference values in the evaluation of renal perfusion using CEUS in dogs under anesthesia.