Contrast-enhanced Ultrasound of the Kidney

This is an investigator-initiated, prospective study designed to evaluate the accuracy of contrast-enhanced ultrasound (CEUS) with microbubble contrast agent (perflutren lipid; Definity®) to identify malignancy in patients with kidney disease, a known risk factor for kidney malignancy, in whom a conventional ultrasound (US) shows an indeterminate cystic kidney lesion. The primary objective of the study is to estimate the sensitivity of CEUS in diagnosing kidney malignancy in patients with a risk factor for kidney malignancy and compare it to the current gold standard test in this patient population. Secondary analysis will include more optimal contrast-enhanced imaging with computed tomography (CT) or magnetic resonance imaging (MRI) in a subset of patients who can receive these studies. The study outcome will lead to immediate clinical application in patients with chronic kidney disease. Given the cost-effectiveness and adverse event profile, it has excellent potential to become established as first line diagnostics in the general patient population as well.