X-Ray

Structures seen on a posteroanterior (PA) chest x-ray. 1 = first rib; 2–10 = posterior aspect of ribs 2–10; AK = aortic knob; APW = aortopulmonary window, BS = breast shadow (labeled only on right); C = carina; CA = colonic air; CPA = costophrenic angle, DA = descending aorta; GA = gastric air; LHB = left heart border (Note: Most of the left heart border represents the left ventricle; the superior aspect of the left heart border represents the left atrial appendage.); LPA = left pulmonary artery; RC = right clavicle (left clavicle not labeled); RHB = right heart border (Note: The right heart border represents the right atrium.); RHD = right hemidiaphragm (left hemidiaphragm not labeled); RPA = right pulmonary artery; T = tracheal air column.




Structures seen on a lateral chest x-ray. A = aorta; CPA = posterior costophrenic angle; LHD = left hemidiaphragm; PHB = posterior heart border (Note: The posterior heart border represents the left atrium superiorly and left ventricle inferiorly; the anterior heart border is not clearly defined on this film but represents the right ventricle.); RA = retrosternal airspace; RHD = right hemidiaphragm; RMF = right major fissure (left major fissure and minor fissures not well visualized on these films but can occasionally be seen); S = scapula; T = tracheal air column.