Pulmonary sequestration occurs when the normal pulmonary arterial connections fail to develop in part or all of a lung. There is an enlarged sytemic artery to the affected segments. The bronchio-alveolar buds do not connect to the bronchial tree. Recurrent infections, abscess formation or cerebral abscess formation (the systemic artery bypassing the normal filtration function of the lungs) may ensue.

Treatment is surgical with resection of the affected segments, after control of the systemic vessel.

A major learning point to remember when dealing with any inflammatory condition particularly of the lower lobes: a major feeding artery may be present in the inferior pulmonary ligament. Be cautious when dividing the IPL as this large vessel may be divided and retract below the diaphragm. The immediate cause for the bleeding may not be obvious and control may be difficult.

Case History

A 21 year old man presented with a 5 year history of recurrent chest infections. Chest Xrays had repeatedly been reported as normal. A bronchoscopy had shown what appeared to be extrinsic compression of basal segmental bronchi on the left.

A magnified view of the CXR does show increased markings in the left lower zone, especially behind the cardiac shadow.

CT showed a multi-loculated cystic mass in the lower lobe. The multi-loculated appearance is well appreciated on the sagittal views

Aortogram demonstrated the presence of a sizeable abnormal systemic artery, arising from the aorta below the diaphragm, passing through the diaphragm to the lung via the inferior pulmonary ligament.

A posterior muscle sparing approach was used. Additional access can be gained by using drain incisions to introduce instruments, as is done in thoracoscopic surgery. In the photo an endoscopic vascular stapler has been placed across the systemic artery feeding an introlobar pulmonary sequestration. The endoscopic vascular stapler can be seen placed across inferior pulmonary ligament. including the feeding vessel.

Once the feeding vessel, which arose from the sub-diaphragmatic aorta, had been stapled and divided, the sequestration was wedged out, preserving most of the lower lobe.


Pulmonary sequestration