Intralobar sequestration of upper lobe of right lung--case reports

Two cases of intralobar sequestration of the right upper lobe, which is supplied by a major anomalous collateral artery from the descending thoracic aorta and also by the upper lobe branch of the right pulmonary artery, are presented. Both cases underwent surgical correction. The plexus of abnormal vessels in the right upper lobe of the lung communicating to the anomalous collateral artery was unexpected. The return pathway into the right pulmonary artery was most unusual. The embryologic explanation of the anomaly and the surgical implications are discussed. The return pathway of the left-to-right shunt by a branch of the pulmonary artery is most unusual and has hitherto not been reported in English literature to the best of the authors' knowledge.