[Radiologic manifestations of pulmonary embolisms as round shadows]

A radiologic finding takes a prominent place in establishing the diagnosis of pulmonary thromboembolism. It may rather vary in appearance, depending on the size of the obturated blood vessel. Changes in the pulmonary parenchyma develop within 24 hours after pulmonary thromboembolism attack occurs. In microembolism, the radiologic finding appears normal. Triangle-shaped shadows characteristic for pulmonary thromboembolism may appear as either round or oval on computerized CT scan. In standard chest X-ray finding, these lesions look like tumorous ones.

Over the period from 1995 to 1997, there were 421 patients treated for pulmonary thromboembolism at the Institute of Pulmonary Diseases in Sremska Kamenica (Yougoslavia), whereas 3.09% of them presented with an oval shadow in a standard chest X-ray or CT finding. The analysis performed in 1981 revealed that majority of patients with pulmonary thromboembolism (11.4%) had round-shaped shadows.

Any round-shaped shadow discovered by both standard chest X-ray and CT findings should be carefully investigated because differential diagnostics includes a variety of diseases.

A round-shaped or oval lung shadow seen in standard chest X-ray or CT finding should be suspected for lung cancer. Patients are therefore submitted to aggressive diagnostic procedures. Pulmonary thromboembolism should also be thought of in order to initiate proper treatment in time.