<prompt> Investigation of choice for bronchiectasisAlpha 1-antitrypsin levelANCADs-DNACT  <response>: Chest CT is more specific for bronchiectasis and is the imaging modality of choice for confirming the diagnosis.CT findings include airway dilationtram track or signet ring sign,lack of bronchial tapering,bronchial wall thickening in dilated airways,inspissated secretions or cysts emanating from the bronchial wall Ref:Harrisons med:18th edition,page no:2143. 