The added value of contrast-enhanced ultrasound in evaluation of indeterminate small solid renal masses and risk stratification of cystic renal lesions.

• Once lipid-rich AML is excluded by the other modalities, sSRM arterial phase hypo-enhancement relative to renal cortex on CEUS yielded high specificity (97.4%) and PPV (98.2%) to diagnose RCC. • When applying the proposed Bosniak Classification 2019, CEUS showed higher sensitivity compared to CT/MRI (100% vs 60%), p value=.0024, in the stratification of cystic renal masses to diagnose malignancy. • CEUS may reduce the number of CT/MRI Bosniak IIF lesions by assigning them to either II or III/IV categories.