Upper Left Quadrant

Lower Left Quadrant

Lower Right Quadrant

Upper Right Quadrant

1. Heart, right atrium
2. Internal thoracic a.
3. Rib 4, right upper lobe, anterior segment
4. Pectoralis major m.
5. Rib 5
6. Horizontal fissure
7. Rib 6

8. Lung, right middle lobe, lateral segment
9. Lung, right oblique fissure, esophageal plexus, and right vagus nerve
10. Rib 7
11. Thoracodorsal a., v., and nerve
12. Latissimus dorsi m.
13. Serratus anterior
14. Lung, right lower lobe, superior segment, and rib 8
15. Esophagus
16. Spinal nerve root and radiate ligament
17. Costovertebral articulation and vertebra T8
18. Azygos vein
19. Trapezius m.
20. Anterior longitudinal ligament

21. Spinal cord
22. Supraspinous ligament and tip of spinous process, T6
23. Spinous process, T7, and theca
24. Inferior articular process, zygapophyseal joint
25. Semispinalis dorsi m.
26. Multifidus m.
27. Thoracic disk 8
28. Radiate ligament
29. Lung, left lower lobe, anterior medial basal segment, and thoracic aorta
30. Intercostal a. and v.
31. Lung, left lower lobe, lateral basal segment, esophageal plexus, and left vagus nerve
32. Long thoracic nerve, lateral thoracic a. and v., and bronchioles
33. Pulmonary a., brs.
34. Latissimus dorsi m. and thoracodorsal a., v., and nerve.
35. Thoracodorsal a. and serratus anterior m.

36. Lung, left upper lobe, lower division (lingular), inferior segment, and coronary sinus
37. Lung, left oblique fissure, and middle and small cardiac vv.
38. Mitral valve and circumflex br., left coronary a.
39. Phrenic nerve and pericardiacophrenic a.
40. Lung, left upper lobe, upper division, anterior segment, myocardium, and left ventricle
41. Pericardial fat
42. Chordae tendineae and papillary m.
43. Left ventricular cavity
44. Anterior interventricular br., left coronary a.
45. Cardiac notch
46. Right ventricle
47. Articular cavity
48. Right atrioventricular valve (tricuspid)
49. Coronary a., right
50. Anterior mediastinum, fat, and sternum, body