Pleural telangiectasia and absence of a pulmonary artery.

The radiological features of absence of a pulmonary artery are often characteristic enough to allow a diagnosis based on the plain radiograph. They include a small hemithorax, ipsilateral displacement of the mediastinum, absence of the corresponding pulmonary artery, and reticular parenchymal densities, generally attributed to bronchial collateral vessels. Six cases are reported; 3 patients had peripheral, hazy, confluent densities and pleural thickening. Aortography disclosed extensive intercostal and subdiaphragmatic transpleural collaterals, which formed telangiectatic networks within the pleura of the oligemic lungs, corresponding to the areas of increased density on the plain radiographs. The appearance of these transpleural collaterals is helpful in diagnosis. Pleural telangiectasia in association with prolonged pulmonary oligemia of any cause indicates significant transpleural collaterals.