Q. Special situations of Pulmonary Embolism?

The CXR is often abnormal in pulmonary embolism. Atelectasis and other focal pulmonary parenchymal abnormalities are the most common findings. Pleural effusions are also common, but usually small and unilateral. Other plain film findings associated with pulmonary embolism
are:

i) Westermark sign: Dilatation of the pulmonary vessels at or proximal to an embolism.

ii) Fleischner's sign: The combination of enlargement of the pulmonary artery due to thrombus, with distal oligemia.

iii) Hampton hump: Hampton hump, a triangular or rounded pleural-based infiltrate with the apex pointed toward the hilum represents infarcted lung in pulmonary embolism.