Two cases of acute pulmonary artery embolism triggered by fresh and chronic mixed-vein thrombosis with a "Blowfish sign".

Ultrasonography and computed tomography of the lower extremities revealed fresh and chronic mixed-vein thrombosis (FCMVTs) presenting the "Blowfish sign," accompanied by pulmonary embolism. FCMVTs presenting the "Blowfish sign" may increase the risk of fatal pulmonary embolism, and its detection by ultrasonography is important for preventing pulmonary embolism.