High-Resolution Chest CT: Practical Clinical Applications

1. High-Resolution Chest CT: Practical Clinical Applications Paul L. Molina, M.D. Department of Radiology University of North Carolina at Chapel Hill

2. Disclosures None

3. Objectives • Identify current clinical indications for the use of HRCT • Review proper technique for performance of HRCT • Summarize the characteristic patterns of abnormality seen on HRCT and the most common diseases resulting in their formation

4. HRCT - Indication • Evaluation of patients with suspected infiltrative lung disease but normal or nonspecific findings on CXR

8. HRCT - Indication • Further characterization of known or suspected diffuse lung disease

12. HRCT - Indication • Evaluation of patients in whom radiographic findings are not in keeping with clinical findings or pulmonary function tests

14. HRCT - Indication • Delineation of disease prior to lung biopsy as a guide to the optimal type and site of biopsy

16. HRCT Technique • Thin collimation (1 mm) • High spatial frequency reconstruction • Windows -700/1000-1500 HU • Prone scans – differentiate atelectasis • Expiratory scans – air trapping

17. HRCT Findings • Septal thickening • Reticular densities • Nodules • Increased lung opacity • Decreased lung opacity

22. Septal Thickening • Pulmonary edema • Lymphangiticcarcinomatosis • Sarcoidosis • Asbestosis • Idiopathic pulmonary fibrosis

28. Reticular Densities • Idiopathic pulmonary fibrosis • Collagen vascular disease • Asbestosis • Chronichypersensitivity pneumonitis • Sarcoidosis

30. UIP

31. Nodular Opacities • Sarcoidosis • Silicosis • Coal worker’s pneumoconiosis • Hypersensitivity pneumonitis • Tuberculosis • Metastatic disease

32. Nodular Opacities • Perilymphatic nodules • Random distribution • Centrilobular nodules

33. Perilymphatic Nodules • Sarcoidosis • Silicosis • Lymphangitic Ca

37. Silicosis

38. Random Nodules • Miliary TB • Hematogenousmets

42. Metastatic adenoca

46. Centrilobular Nodules • Endobronchial spread of TB or other infection • Hypersensitivity pneumonitis • Endobronchial tumor spread

48. Nodular Opacities • Perilymphatic nodules • Random distribution • Centrilobular nodules

50. Increased Lung Opacity • Ground-glass opacity • Air-space consolidation