Radiology Pathology Clinical 1 11/7/2018 Role of HRCT Diagnosis - PDF document

11/7/2018 Radiology Approach to ILD Brett M. Elicker, MD University of California, San Francisco Radiology Pathology Clinical 1

11/7/2018 Role of HRCT • Diagnosis • Fibrosis vs. inflammation • Next step in management • Response to treatment Confidence in diagnosis CT + clinical = CT = diagnostic pattern diagnostic pattern CT = nonspecific 2

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11/7/2018 Clinical Context History History History History History Diagnosis Diagnosis Diagnosis Diagnosis Diagnosis Bird/mold Bird/mold Bird/mold Bird/mold Hypersensitivity Hypersensitivity Hypersensitivity Hypersensitivity exposure exposure exposure exposure pneumonitis pneumonitis pneumonitis pneumonitis Respiratory Respiratory Respiratory Smoking Smoking Smoking bronchiolitis bronchiolitis bronchiolitis Connective Connective Follicular Follicular tissue disease tissue disease bronchiolitis bronchiolitis Acute symptoms Viral infection only 4

11/7/2018 End stage IPF Markedly reduced TLC and DLCO End stage constrictive bronchiolitis Inspiration Expiration Markedly reduced FEV1 5

11/7/2018 HRCT may show reduced sensitivity for: • Small airways diseases – Constrictive broncholitis – Hypersensitivity pneumonitis – Asthma • Emphysema • Pulmonary hypertension Fibrosis vs. Inflammation No GGO ‐ fibrosis GGO ‐ inflammation GGO ‐ fibrosis 6

11/7/2018 HRCT guides further work-up Bronchoscopy Sputum VATS HRCT: follow-up after tx • Disease that is below the threshold of PFTs • Mixed disease (e.g. airways and fibrosis) • Multi-compartmental disease (e.g. lung and pleura) • Acute symptoms 7

11/7/2018 Interpreting HRCTs • 1. What is the most significant finding? • 2. What is the distribution within the lungs? • 3. Are there ancillary findings that increase specificity? • 4. Is there helpful clinical information? Case #1: What is the most significant finding? Traction bronchiectasis Irregular reticulation Honeycombing 8

11/7/2018 Case #1: What is the distribution in the lung? Subpleural Basilar Case #1: Are there are associated findings that increase specificity? Associated finding Associated finding Associated finding Associated finding Associated finding Disease Disease Disease Disease Disease (in setting of fibrosis) (in setting of fibrosis) (in setting of fibrosis) (in setting of fibrosis) (in setting of fibrosis) Mosaic perfusion and/or air Mosaic perfusion and/or air Mosaic perfusion and/or air Mosaic perfusion and/or air Hypersensitivity Hypersensitivity Hypersensitivity Hypersensitivity trapping trapping trapping trapping pneumonitis pneumonitis pneumonitis pneumonitis Hypersensitivity Hypersensitivity Hypersensitivity Diffuse nodules Diffuse nodules Diffuse nodules pneumonitis, sarcoidosis pneumonitis, sarcoidosis pneumonitis, sarcoidosis Connective tissue disease, Connective tissue disease, Ground glass opacity or Ground glass opacity or hypersensitivity hypersensitivity consolidation consolidation pneumonitis, drugs pneumonitis, drugs Connective tissue disease, Cysts smoking (i.e. desquamative interstitial pneumonia) 9

11/7/2018 Case #1: Is there helpful clinical information? Clinical clue Clinical clue Clinical clue Clinical clue Clinical clue Disease Disease Disease Disease Disease Hypersensitivity Hypersensitivity Hypersensitivity Hypersensitivity Inhaled exposure Inhaled exposure Inhaled exposure Inhaled exposure pneumonitis, pneumonitis, pneumonitis, pneumonitis, pneumoconiosis pneumoconiosis pneumoconiosis pneumoconiosis Drug exposure Drug exposure Drug exposure Drug toxicity Drug toxicity Drug toxicity Clinical or physical exam Clinical or physical exam Rheumatoid, scleroderma, Rheumatoid, scleroderma, findings of connective tissue findings of connective tissue myositis, lupus, Sjogren’s, myositis, lupus, Sjogren’s, disease (CTD) disease (CTD) mixed CTD mixed CTD Idiopathic pulmonary Idiopathic fibrosis, hypersensitivity pneumonitis, sarcoidosis Case #1: summary and diagnosis • 1. Fibrosis with honeycombing Usual • 2. Subpleural/basilar Idiopathic interstitial pulmonary pneumonia distribution fibrosis • 3. No associated findings • 4. No clinical clues 10

11/7/2018 Usual interstitial pneumonia Radiology Pathology Idiopathic Clinical Idiopathic Clinical Histologic Pattern Histologic Pattern Associated Diseases Associated Diseases Syndrome Syndrome Usual interstitial Usual interstitial Idiopathic pulmonary Idiopathic pulmonary Connective tissue disease Connective tissue disease pneumonia pneumonia fibrosis fibrosis (CTD), drugs, asbestosis (CTD), drugs, asbestosis CTD, drugs, CTD, drugs, Nonspecific interstitial Nonspecific interstitial Idiopathic NSIP Idiopathic NSIP hypersensitivity hypersensitivity pneumonia (NSIP) pneumonia (NSIP) pneumonitis (HP) pneumonitis (HP) Desquamative interstitial Desquamative interstitial Smoking, CTD, drugs, toxic Smoking, CTD, drugs, toxic Idiopathic DIP Idiopathic DIP pneumonia (DIP) pneumonia (DIP) inhalations inhalations CTD, drugs, infections, CTD, drugs, infections, Organizing pneumonia Organizing pneumonia Cryptogenic OP Cryptogenic OP chronic eosinophilic chronic eosinophilic (OP) (OP) pneumonia, HP pneumonia, HP Post ‐ viral, CTD, drugs, Post ‐ viral, CTD, drugs, Constrictive bronchiolitis Constrictive bronchiolitis Idiopathic CB Idiopathic CB graft vs. host disease, lung graft vs. host disease, lung (CB) (CB) transplant rejection transplant rejection Infection, aspiration, Infection, aspiration, Acute interstitial Acute interstitial Diffuse alveolar damage Diffuse alveolar damage trauma, sepsis, trauma, sepsis, pneumonia pneumonia pancreatitis, etc. pancreatitis, etc. 11

11/7/2018 UIP: clinical clues IPF Asbestosis Drug Rheumatoid UIP Criteria Raghu et al. Am J Respir Crit Care Med. 2018; 198: e44. Confidence in Category Criteria Distribution IPF •Honeycombing Subpleural High ( ≥ 95%) UIP •Traction bronchiectasis and basilar •Lack of atypical features Intermediate •Reticulation Subpleural to high (60 ‐ Probable UIP •Traction bronchiectasis and basilar 90%) •No honeycombing •Mild reticulation Intermediate • No traction bronchiectasis Subpleural Indeterminate for UIP (?) OR and basilar •Mild ground glass opacity NOT Suggestive of Low (25%) •Features atypical for UIP subpleural or alternative diagnosis basilar 12

11/7/2018 Do NOT overall UIP! • Honeycombing mimics • Incorrect distribution • Presence of atypical features Honeycombing • Honeycombing features – Air density – Round with fairly thick wall – Always involves subpleural lung – Single or multiple layers – Associated sign(s) of fibrosis 13

11/7/2018 Honeycombing mimics Emphysema Traction bronchiectasis Cystic lung disease Sjogren’s disease: nonspecific and lymphoid interstitial pneumonia 14

11/7/2018 Distribution Axial Coronal Associated findings • Mosaic perfusion Bilateral in ≥ 3 lobes (inspiration) • Air trapping (expiration) • Nodules • Ground glass opacity • Consolidation • Cysts 15

11/7/2018 What diseases/patterns may mimic IPF on HRCT? • Nonspecific interstitial pneumonia (NSIP) • Desquamative interstitial pneumonia • Hypersensitivity pneumonitis Nonspecific interstitial pneumonia Subpleural sparing 7 years later 16

11/7/2018 Desquamative interstitial pneumonia 5 years before Hypersensitivity pneumonitis 17

11/7/2018 Unknown case Headcheese • Head cheese is in fact not a cheese, but rather a terrine made of meat taken from the head of a calf or pig (sometimes a sheep or cow) that would not otherwise be considered appealing. Headcheese sign 18

11/7/2018 Ground glass opacity • Changes below resolution of CT • Compartments of lung effective – Alveolar – Interstitial – Mixed • Broad differential diagnosis • Acute vs. chronic symptoms Mosaic perfusion • Geographic areas of lucent lung • Reflects areas of reduced perfusion • Causes – Airways disease – Vascular disease 19

11/7/2018 Mosaic perfusion (lucent lung abnormal) Vessel size Air trapping Very discrepancy geographic Insp. Exp. Headcheese sign • Three components – Infiltrative (ground glass) – Obstructive (mosaic perfusion) – Intermediate density lung (normal) • Both in significant amounts • Diagnosis usually HP 20

11/7/2018 Hypersensitivity Pneumonitis *Headcheese courtesy of Oscar Meyer Radiology Approach to ILD Brett M. Elicker, MD University of California, San Francisco 21