Intraoperative ultrasound: Determination of the presence and extent of vena caval tumor thrombus

Abstract

Objectives To report and discuss five cases of renal cell carcinoma (RCC) inwhich preoperative imaging studies were equivocal with regard to the presence and extent of vena caval tumor thrombus or in which dynamic intraoperative imaging of the vena cava was advantageous. Methods We reviewed the cases of five patients who had conflicting preoperative imaging studies and reviewed the literature applying to this clinical situation. Results Two patients whose preoperative magnetic resonance imaging studies suggestedinferior vena cavai tumor thrombus were shown, on intraoperative color Doppler ultrasound, not to have tumor thrombus but rather turbulent flow within the vena cava mimicking thrombus. In two patients intraoperative ultrasound (IOUS) was used to image the position of the tumor thrombus as it was manipulated to allow for safe vena caval clamp placement. In one patient we used real-time imaging to visualize thrombus extraction from the heart. Conclusions Intraoperative ultrasound real-time imaging is beneficial in two specific situations: in those cases in which the presence of renal vein or inferior vena cava involvement is equivocal based on preoperative imaging techniques and when there is a need to identify intraoperatively the limits of a known tumor thrombus to allow subsequent safe placement of a caval clamp.