Approach to lung opacities This is hard! You will not be an expert - PDF document

10/9/2019 Algorithmic Approach to Lung Opacities Brett M. Elicker, MD University of California, San Francisco Approach to lung opacities • This is hard! • You will not be an expert today • Approach • Practice • Think like a pathologist 1

10/9/2019 Categories of lung opacities • 1. Consolidation • 2. Interstitial • 3. Airways • 4. Other 2

10/9/2019 Alveolar Interstitial 3

10/9/2019 Airways Not applicable 4

10/9/2019 Consolidation • Confluent opacity • Fluffy around periphery • Air bronchograms • Lack of volume loss Confluent opacity, no volume loss 5

10/9/2019 Air bronchograms Consolidation • Acute vs. chronic symptoms • Distribution • Acuity of changes • Differential diagnosis in acute setting – Edema – Acute lung injury – Infection 6

10/9/2019 Invasive mucinous adenocarcinoma baseline 2 month f/u 7

10/9/2019 Comparison Signs of atelectasis: volume loss Fissure Deviation of displacement mediastinal structures Elevated diaphragm 8

10/9/2019 Interstitial opacities Nodules Lines 9

10/9/2019 Nodules: diff dx • Hematogenous spread – Miliary tuberculosis – Miliary fungal infection (e.g. cocci) – Metastases • Lymphatic spread – Sarcoidosis – Lymphangitic spread of tumor – Pneumoconioses (e.g. silica) Histoplasmosis 10

10/9/2019 Miliary tuberculosis Interstitial: lines 11

10/9/2019 Causes of interstitial lines • Edema Kerley-b lines may be present • Malignancy • Fibrotic lung diseases (this These lines are typically thick, wavy and irregular is a long list) Linear opacities 12

10/9/2019 Pulmonary edema (kerley-b lines) Edema: alveolar + interstitial 13

10/9/2019 Reticular opacities (distribution) • Mid-lower lobe predominant – Idiopathic pulmonary fibrosis – Connective tissue disease – Drugs – Asbestosis – Hypersensitivity pneumonitis • Upper lobe predominant – Sarcoidosis – Prior TB/fungus – Pneumoconioses 14

10/9/2019 Idiopathic pulmonary fibrosis Hypersensitivity pneumonitis 15

10/9/2019 Tuberculosis 16

10/9/2019 Airways disease • Circular • Tubular 17

10/9/2019 Differential diagnosis of airways disease • Mild: • Severe: – Asthma – Bronchiolitis obliterans – Viral infection – Immunodeficiency – Chronic bronchitis – Ciliary dyskinesia – Etc. – Cystic fibrosis – ABPA – Tuberculosis – Cartilage diseases Cystic fibrosis 18

10/9/2019 Which compartment of lung is affected? Solitary pulmonary nodule: differential diagnosis • Granuloma • Hamartoma • Primary bronchogenic carcinoma • Metastasis • Lots of others 19

10/9/2019 Nodules: benign vs. malignant Benign Malignant Small size Large size Smooth border Spiculated border No or irregular Diffuse calcification calcification Stability over time Growth over time Nodule: size 20

10/9/2019 Nodule: calcification Nodule borders 21

10/9/2019 So you see a nodule on CXR… • 1. Is it actually a nodule? ? nodule 22

10/9/2019 Shallow obliques ? nodule 23

10/9/2019 Apical lordotic So you see a nodule on CXR… • 1. Is it actually a nodule? • 2. Look for prior films? • 3. Is diffuse calcification present? 24

10/9/2019 Dual energy subtraction x-ray So you see a nodule on CXR… • 1. Is it actually a nodule? • 2. Look for prior films? • 3. Is diffuse calcification present? • 4. Get a CT scan or a follow-up CXR 25

10/9/2019 Category Subcategory CXR features Common causes •Confluent opacities •Edema Alveolar •Air bronchograms •Acute lung injury •Fluffy edges •Infection •Tuberculosis •Small, well ‐ defined nodules •Fungal infection Nodules •Opacities not confluent •Metastases •Normal lung between nodules •Sarcoidosis Interstitial •Thin, fine, delicate lines Lines •Pulmonary edema •Lines at periphery of lung (kerley ‐ b) •Cancer (kerley ‐ b) Lines •Fibrotic lung •Thick, wavy, irregular lines (reticular) disease •Circular or tubular Airways •Numerous causes •Thin or thick walled •Lung cancer Not in a single •One or a few nodules ( ≤ 3 cm) or •Metastasis compartment masses (>3 cm) •Granuloma •Hamartoma Not all cases are straightforward 26

10/9/2019 Well-defined: Ill-defined: interstitial alveolar Extensive nodules: interstitial 27

10/9/2019 Peribronchial cuffing: interstitial Airways: circles and tubes 28

10/9/2019 Algorithmic Approach to Lung Opacities Brett M. Elicker, MD University of California, San Francisco 29