(A) A 9 Mhz linear ultrasound transducer probe covered with a sterile probe cover. (B) A sterile linear ultrasound transducer probe was applied perpendicular to the long axis of sternum. The needle is positioned at the middle of the transducer probe and punctures the skin using “out-of-plane” technique under the total ultrasound guidance. (C) A typical ultrasonogram of sternum. The depth from the skin to the sternum is measured as approximately 1 cm with its width approximately 1 cm. Sternum, a bony structure, has high adsorption coefficient of ultrasound, and is visualized as hypoechoic lesion surrounded by the hyperechoic periosteum. Beneath the sternum, a blood flow of ascending aortae is clearly visualized using B-mode ultrasonogram with color flow imaging. (D) A longitudinal view of the mediastinum just beside the sternum. In the center of the view, a thoracic costae is identified as a hypoechoic circle surrounded by the hyperechoic periosteum. Beneath the thoracic costae, blood flow of the ascending aortae is identified using B-mode sonogram with color flow imaging.