What's on a Plain CXR
1 Clavicular companion shadow
2 Trachea
3 Aortic arch (knob)
4 Lateral border of descending aorta
5 Main pulmonary artery
6 Azygo-esophageal line
7 Posterior segment of right 7th rib
8 Anterior segment of right 5th rib
9 Left lateral costophrenic sulcus
10 Gastric air bubble

1 Posterior junction line
2 Proximal right clavicle
3 Aortic arch (knob)
4 Coracoid process of scapula
5 Inferior angle of scapula
6 Carina
7 Right main bronchus
8 Left main bronchus
9 Right minor (horizontal) fissure
10 Right atrium
11 Left ventricle
12 Medial skinfold of left breast
13 Medial border of scapula

1 Aortic arch (knob)
2 Carina of trachea
3 Right lateral border of superior vena cava
4 Left lateral border of descending aorta
5 Left main bronchus
6 Left upper lobe bronchus
7 Left lower lobe bronchus
8 Azygo-esophageal line
9 Right hemidiaphragm

1 Humeral head
2 Right minor (horizontal) fissure
3 Right hemidiaphragm
4 Left hemidiaphragm
5 Posterior margin of inferior vena cava
6 Posterior pleural surface of right lung
7 Posterior pleural surface of left lung
8 Gastric air bubble
9 Left posterior costophrenic sulcus
10 Cortical margin of scapula

1 Trachea
2 Aortic arch
3 Manubrium
4 Body of sternum
5 Sternomanubrial junction
6 Oblique (major) fissure

A Azygous fissure
B Lateral border of left subclavian artery
C Aortic arch
D Main pulmonary artery
E Right lower lobe pulmonary venous branch
F Left lower lobe pulmonary artery branch

Humeral head (ossification center)
Coracoid process
Left ventricle
Right atrium
