Single left pulmonary vein with normal pulmonary venous drainage: association with partial anomalous pulmonary venous return.

An unusual case of a single left pulmonary vein draining the left lung and joining the left atrium without venous obstruction is reported. This anomaly occurred in association with partial anomalous pulmonary venous return from the upper lobe of the right lung to the superior vena cava. A similar case has been previously reported from our laboratory. The diagnosis of a single left pulmonary vein can be made by routine chest roentgenography because of the characteristic radiologic appearance of this anomaly. It is important to distinguish this benign entity from more ominous pulmonary radiodensities.