ABSTRACT
The right pulmonary artery lies in the mid part of the hilum and is surrounded by structures which might be expected to make it less distinct. When reading chest radiographs, it is always essential to study the pulmonary vessels, to note the normal anatomy and any deviations from this. Pulmonary arteries and veins may often be differentiated by their different branching patterns. The segmental arteries tend to continually bifurcate with axial notching and follow the bronchi, whilst the veins have branches joining from the side, and roughly maintain their original direction, the inferior veins running almost horizontally. Thinning of vessels in an area may occur acutely with pulmonary embolism. The anomaly is often associated with diaphragmatic abnormalities, duplication, a hernia, reduplication cysts or other congenital abnormalities such as cystic adenomatoid malformation.
