Regarding the ultrasonic manifestations of neuroblastoma, they typically occur at the site of the neuroblastoma. Some neuroblastomas occur in the retroperitoneal space, such as near the adrenal glands or alongside the spine, usually presenting direct and indirect signs. Direct signs often manifest as a large tumor volume, often crossing the midline, characterized internally primarily by hypoechoic areas with significant returns unevenness, and rich blood flow around the tumor. Some patients may exhibit tumor calcification, which can cause encasement or invasion of major retroperitoneal vessels, but less commonly invasion resulting in acid efflux. Indirect signs mainly include causing renal hydronephrosis, potentially leading to enlargement of surrounding lymph nodes, and causing ascites.