Isolated partial anomalous origin of a branch pulmonary artery from the descending aorta.

The condition of partial anomalous origin of a branch pulmonary artery from the descending aorta could be found in several diseases and should be carefully differentiated. We report an unusual case of anomalous systemic arterial supply to normal basal segments of the left lower lung and another case of intralobar pulmonary sequestration. These two cases were treated successfully by transarterial embolisation using the Amplatzer Vascular Plug. We also set up a diagnostic algorithm to differentiate these diseases from anomalous systemic arterial supply to the pulmonary region. It is possible to make the correct diagnosis using the step-by-step diagnostic algorithm and careful interpretation of chest computed tomography angiography.