Perfusion abnormalities of kidney parenchyma: microvascular imaging with contrast-enhanced color and power Doppler ultrasonography--preliminary results

The purpose of this study was to evaluate the feasibility of microvascular imaging using contrast‐enhanced color and power Doppler sonography. Ten patients with a focal lesion of the kidney were examined. Three patients were investigated with the polymeric butylcyanacrylate‐based contrast agent SHU 563A, and the remaining patients were investigated with the galactose‐based agent Levovist. It was possible to observe the microvascularization with Levovist during the blood pool phase of the agent over a period of 1 to 3 s at 1 min and 2 min after injection. With SHU 563A, microvascular imaging was possible 0.50 s after injection and lasted for 10.35 min. No intratumoral signals were seen in cysts (n = 6) and the investigated abscess. Weak intratumoral polychromatic effects were observed in both renal cell carcinomas in this series. Metastasis could be differentiated from healthy parenchyma due to lack of the polychromatic effect. SHU 563A is appropriate for performing microvascular imaging. The Levovist‐induced polychromatic effects are smaller, of shorter duration, and observable only during the blood pool phase; thus, the expected diagnostic benefit is limited.