<prompt> Sequestration lung is best diagnosed byCT ScanMRIBarium swallowAngiography  <response>: Pulmonary sequestration:It is an embryonic mass of lung tissue that has no identifiable bronchial communication and that receives blood supply from 1 or more anomalous systemic aeriesClassified as extralobar 25 and intralobar 75Demonstration of dominant feeding vessel, usually from the aoa or its major vessels, and venous drainage to the pulmonary veins suggests the diagnosisThe definitive diagnosis is made by using angiography conventional, CTA, MRARef: Sumer Sethi 4e p35 