The present chapter highlights the most important information about microcirculation and its evaluation using contrast-enhanced ultrasonography (CEUS). In the beginning it outlines some general considerations about microcirculation, together with its morphological and physiological particularities under normal and pathological circumstances. The ultrasonographic (US) evaluation of vascularity is based on the Doppler technique and the harmonic technique using contrast agents. Then it presents briefly the Doppler ultrasound (DUS) and discusses its most important current and emerging indications. CEUS is presented extensively, covering the fundamentals of sonographic contrast agents, harmonic imaging and quantification techniques. A special focus is placed not only on the current and emerging indications of CEUS but also on the advantages and limitations of the method. This chapter also incorporates information about experimental CEUS applications and future perspectives. CEUS is the recommended US method for the characterization of microcirculation. The results of the examination are displayed in real-time, under the eyes of the examiner, while the quantitative assessment of the contrast agent kinetics parameters is easy to perform. This method allows a precise definition of the healthy or pathologic state of an organ and the follow-up of treatment response.
Part of the book: Microcirculation Revisited
Nowadays, kidney tumor diagnosis benefits from large and highly accurate imagistic methods. A new imagistic method is contrast-enhanced ultrasound (CEUS) that accurately depicts the circulatory pattern of tumors. In kidney pathology, any mass or even capsular deformation depicted by B mode ultrasound represents an indication for CEUS. The kidney is completely and uniformly vascularized. In cystic tumors, there is a lack of contrast loading. In “impure” cystic masses (Bosnian 3 and 4), CEUS reveals vascularized septa and walls. In malignant tumors, accelerated and heterogeneous loading of contrast agent is observed in arterial phase followed by early, inhomogeneous washout of the contrast agent compared to normal renal parenchyma. In the abscesses, the appearance is the early loading of the walls associated with moderate hyperemia of the normal circulatory bed. This chapter details the CEUS in kidney tumor pathology, emphasizing the accurate information for the circulatory pattern of renal masses. It requires correlations with clinical data and information provided by other imaging explorations to make a final diagnosis.
Part of the book: Evolving Trends in Kidney Cancer