Multimodality-imaging manifestations of primary renal-allograft synovial sarcoma: First case report and literature review

Figure 4 Contrast-enhanced ultrasound wash-in and wash-out characteristics of the neoplasms. A: The cortical-phase contrast-enhanced ultrasound image showing twisted, branchlike, and tortuous vessel perfusion (yellow arrow); B-D: The neoplasms manifested as heterogeneous, slight hyper-enhancement consistently, and no clear earlier wash-out than the peripheral parenchyma could be seen. Pseudo-capsule surrounding the neoplasm could be seen as a slightly higher enhancement ring around the mass compared with normal peripheral parenchyma (yellow arrows).