Bronchiectasis

• Irreversible bronchial dilitation from chronic infection
• Secondary to proximal airway obstruction (infection) or congenital abnormaility (cystic fibrosis, marfan's syndrome, kartagener's syndrome)
• Larger than accompanying pulmonary artery, signet ring sign
• Lack of tapering or bronchi within 1cm of pleura.
• Cylindric, varicose or cystic forms correspond to mild, moderate and severe

Upper Lobe - CF, ABPA Anterior - MAC Unilateral - infectious Low Lobe - ciliary diskinesia, immune deficiency, aspiration