Fig. 16.
Ultrasound (US)-guided thoracic paravertebral blocks using a sagittal transducer. (A) Sagittal cross-section at thoracic level T4/T5 at approximately 3 cm lateral of the midline. (B) Illustration depicting transducer position and needle trajectory for a medial technique with caudal to cranial angulation (8 and 9). Continuous line = in-plane technique; dotted line = out-of-plane technique. The arrow numbers refer to figure 5. A = anterior; es = erector spinae muscle; I = inferior; P = posterior; r = rib; rhomb = rhomboid muscle; S = superior; SCTL = superior costotransverse ligament (pink); TP = transverse process; trap = trapezius muscle. Red, blue, and yellow indicate artery, vein, and nerve, respectively.