Figure 1.

Distribution of the cervical lymph nodes. IA, IB, IIA, IIB, III, IV, VA, VB, and VI: lymphatic group numbers. P: parotid gland; SMG: submandibulary gland; TRP: trapezius muscle; OH: omohyoid muscle; TCA: thyrocervical artery. (a) The schema of the central group. A: prelaryngeal group. B: pretracheal group. C: left paratracheal group. C1: right paratracheal posterolateral group. C2: right paratracheal anteromedial group. HB: hyoid bone; TI: isthmus of the thyroid; AA: arcus aorta; DA: descending aorta; BSA: brachiocephalic artery; SCA: subclavian artery; CCA: common carotid artery; VCS: vena cava superior; RBSV: right brachiocephalic vein; LBSV: left brachiocephalic vein; SCV: subclavian vein; VJI: vena jugularis interna. Group VII: seventh cervical lymphatic group. Dark black line: sternal notch. (b)