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What is CT scan showing base of lung with cavitary lesions and explain in detail?
(C) Bronchiectasis # This is a Transverse high-resolution CT scans obtained in a 40-year-old man with bronchiectasis. Scan shows small-airway disease denoted by centrilobular and tree-in-bud (black arrows) opacities and bronchiectasis in the left upper lobe. Bronchiectasis in the upper lobe was assigned a grade of 1, with grade 1 (white arrows) bronchial wall thickening. In the apical segments of the lower lobes, grade 2 (arrowheads) bronchial wall thickening also is present. Scan shows a combination of grade 1 (arrows) and 2 (arrowheads) bronchial wall thickening in the basal segments of the lower lobes with an overall bronchial wall thickening score of 1.5. Extent of bronchiectasis was evaluated as grade 3 in the right lower lobe and grade 2 in the left lower lobe. Scan shows mosaic attenuation in both upper lobes. Expiratory scan shows air trapping. Hypoattenuating areas (*) were confirmed to be caused by air trapping in d.> Bronchiectasis is defined as localized, irreversible dilatation of part of the bronchial tree. Involved bronchi are dilated in- flamed, and easily collapsible, resulting in airflow obstruction and impaired clearance of secretions.> Bronchiectasis is associated with a wide range of disorders, but it usually results from necrotizing bacterial infections, such as infections caused by the Staphylococcus or Klebsiella species or Bordetella pertussis.> Diagnosis of bronchiectasis is based on a clinical history of daily viscid sputum production and characteristic computed tomography (CT) scan findings.> Chest radiography is usually the first imaging examination, but findings are often nonspecific & images may appear normal.> High-resolution computed tomography (HRCT) scanning has become the imaging modality of choice for demonstrating or ruling out bronchiectasis and its extent.> HRCT scanning also helps clinicians to evaluate status of surrounding lung tissue & exclude other lesions such as neoplasms.