
- •Preface
- •Contents
- •Pattern Approach for Lung Imaging
- •1: Nodule
- •Solitary Pulmonary Nodule (SPN), Solid
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Lung Cancer (Solid Adenocarcinoma)
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Carcinoid or Atypical Carcinoid
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •BALT Lymphoma
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Tuberculoma
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Hamartoma
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Sclerosing Hemangioma
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Ground-Glass Opacity Nodule
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Atypical Adenomatous Hyperplasia (AAH)
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Adenocarcinoma in Situ (AIS)
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Minimally Invasive Adenocarcinoma (MIA)
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •2: Mass
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Pulmonary Sarcoma
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Progressive Massive Fibrosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Actinomycosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •3: Consolidation
- •Lobar Consolidation
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Lobar Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Invasive Mucinous Adenocarcinoma
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Infarction
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Patchy and Nodular Consolidation
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Airway-Invasive Pulmonary Aspergillosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Cryptococcosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •IgG4-Related Lung Disease
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Lymphomatoid Granulomatosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •4: Beaded Septum Sign
- •Diseases Causing the Sign
- •Distribution
- •Clinical Considerations
- •References
- •5: Comet Tail Sign
- •Diseases Causing the Sign
- •Distribution
- •Clinical Considerations
- •Rounded Atelectasis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •6: CT Halo Sign
- •Diseases Causing the Sign
- •Distribution
- •Clinical Considerations
- •Angioinvasive Pulmonary Aspergillosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Metastatic Hemorrhagic Tumors
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Endometriosis with Catamenial Hemorrhage
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •7: Galaxy Sign
- •Diseases Causing the Sign
- •Distribution
- •Clinical Considerations
- •Galaxy Sign in Pulmonary Tuberculosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •8: Reversed Halo Sign
- •Diseases Causing the Sign
- •Distribution
- •Clinical Considerations
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Mucormycosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Lymphomatoid Granulomatosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •9: Tree-in-Bud Sign
- •Diseases Causing the Sign
- •Distribution
- •Clinical Considerations
- •Aspiration Bronchiolitis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Foreign-Body-Induced Pulmonary Vasculitis (Cellulose and Talc Granulomatosis)
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •Diseases Causing the Sign
- •Distribution
- •Clinical Considerations
- •Bronchial Atresia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Bronchial Tuberculosis and Mucoid Impaction
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Foreign-Body Aspiration
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Allergic Bronchopulmonary Aspergillosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •11: Lobar Atelectasis Sign
- •Disease Causing the Sign
- •Distribution
- •Clinical Considerations
- •Right Upper Lobar Atelectasis
- •Left Upper Lobar Atelectasis
- •Right Middle Lobar Atelectasis
- •Lower Lobar Atelectasis
- •References
- •Cavity
- •Diseases Causing the Cavity
- •Distribution
- •Clinical Considerations
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Langerhans Cell Histiocytosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Septic Pulmonary Embolism
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Cavitary Pulmonary Tuberculosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Paragonimiasis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Cyst
- •Diseases Causing the Cyst
- •Distribution
- •Clinical Considerations
- •Blebs and Bullae
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Sequestration
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Intrapulmonary Bronchogenic Cyst
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Traumatic Lung Cysts
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •References
- •Mosaic Attenuation
- •Diseases Causing the Mosaic Attenuation Pattern
- •Distribution
- •Clinical Considerations
- •Cystic Fibrosis
- •Pathology and Pathogenesis
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Constrictive Bronchiolitis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Chronic Pulmonary Thromboembolism
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Idiopathic Pulmonary Arterial Hypertension
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Airway Disease (Bronchiectasis and Bronchiolectasis)
- •Distribution
- •Clinical Considerations
- •Swyer-James-MacLeod Syndrome
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Dyskinetic Cilia Syndrome
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •14: Air-Crescent Sign
- •Diseases Causing the Sign
- •Distribution
- •Clinical Considerations
- •Aspergilloma
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Rasmussen’s Aneurysm
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •15: Signet Ring Sign
- •Diseases Causing the Sign
- •Distribution
- •Clinical Considerations
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •16: Interlobular Septal Thickening
- •Smooth Septal Thickening
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Pulmonary Edema
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Niemann–Pick Disease
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •Nodular Septal Thickening
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Pulmonary Lymphangitic Carcinomatosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT-Pathology Comparisons
- •Patient Prognosis
- •References
- •17: Honeycombing
- •Honeycombing with Subpleural or Basal Predominance
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Asbestosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Honeycombing with Upper Lung Zone Predominance
- •Diseases Causing the Pattern and Distribution
- •Distribution
- •Clinical Considerations
- •Idiopathic Familial Pulmonary Fibrosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Chronic Hypersensitivity Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •End-stage Fibrotic Pulmonary Sarcoidosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •18: Small Nodules
- •Small Nodules with Centrilobular Distribution
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Mycoplasma Pneumoniae Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Diffuse Panbronchiolitis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Follicular Bronchiolitis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Tumor Embolism
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Pneumoconiosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Sarcoidosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Alveoloseptal Amyloidosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Small Nodules with Random (Miliary) Distribution
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Miliary Tuberculosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Miliary Metastasis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •19: Multiple Nodular or Mass(-like) Pattern
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Pulmonary Metastasis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Lymphoma
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Amyloidomas
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •ANCA-Associated Granulomatous Vasculitis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •Ground-Glass Opacity with Reticulation and Fibrosis
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Ground-Glass Opacity with Reticulation, but without Fibrosis (Crazy-Paving Appearance)
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Pneumocystis jirovecii Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Lipoid Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pulmonary Alveolar Proteinosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Mucinous Adenocarcinoma or Adenocarcinoma in Situ, Diffuse Form
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Desquamative Interstitial Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Ground-Glass Opacity without Reticulation, with Small Nodules
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Subacute Hypersensitivity Pneumonitis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Cytomegalovirus Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Diffuse Alveolar Hemorrhage
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Ground-Glass Opacity without Reticulation, Diffuse Distribution
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Acute Hypersensitivity Pneumonitis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Acute Eosinophilic Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •22: Consolidation
- •Consolidation with Subpleural or Patchy Distribution
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Cryptogenic Organizing Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Chronic Eosinophilic Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Churg–Strauss Syndrome
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Radiation Pneumonitis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Consolidation with Diffuse Distribution
- •Diseases Causing the Pattern
- •Distribution
- •Clinical Considerations
- •Viral Pneumonias
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Acute Interstitial Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Diffuse Alveolar Hemorrhage
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •23: Decreased Opacity with Cystic Walls
- •Cavities
- •Diseases Causing Cavities
- •Distribution
- •Clinical Considerations
- •Rheumatoid Lung Nodules
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Cavitary Metastasis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Cysts
- •Diseases Causing Multiple Cysts
- •Distribution
- •Clinical Considerations
- •Lymphangioleiomyomatosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Lymphocytic Interstitial Pneumonia
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •Emphysema
- •Distribution
- •Clinical Considerations
- •Centrilobular Emphysema
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •Patient Prognosis
- •Paraseptal Emphysema
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •Patient Prognosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •Patient Prognosis
- •References
- •24: Decreased Opacity without Cystic Walls
- •Mosaic Attenuation, Vascular
- •Distribution
- •Clinical Considerations
- •Airway Diseases Causing Mosaic Attenuation
- •Distribution
- •Clinical Considerations
- •Asthma
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •Distribution
- •Clinical Considerations
- •Cystic Fibrosis
- •Pathology and Pathogenesis
- •Symptoms and Signs
- •CT Findings
- •CT–Pathology Comparisons
- •Patient Prognosis
- •References
- •26: Pneumonia
- •Lobar Pneumonia
- •Bronchopneumonia
- •Interstitial Pneumonia
- •27: Drug-Induced Lung Disease
- •Interstitial Pneumonitis and Fibrosis
- •Eosinophilic Pneumonia
- •Cryptogenic Organizing Pneumonia
- •Diffuse Alveolar Damage
- •Hypersensitivity Pneumonia
- •References
- •Systemic Lupus Erythematosus (SLE)
- •Rheumatoid Arthritis (RA)
- •Progressive Systemic Sclerosis (PSS)
- •Sjögren’s Syndrome
- •Mixed Connective Tissue Disease
- •Ankylosing Spondylitis
- •References

58 |
6 CT Halo Sign |
|
|
Fig. 6.3 Hemorrhagic metastasis in a 52-year-old woman with renal cell carcinoma. Lung window of CT (5.0-mm section thickness) scan obtained at level of the interior pulmonary vein shows multiple solid nodules surrounded by ground-glass opacity, suggesting hemorrhagic metastasis
Fig. 6.4 Nodules with halo sign in a 28-year-old man with melanoma. Lung window of CT (5.0-mm section thickness) scan obtained at level of the interior pulmonary vein shows multiple variable-sized nodules (arrows) having surrounding halo (hemorrhagic metastases)
CT–Pathology Comparisons |
Symptoms and Signs |
A halo of ground-glass opacity surrounding metastatic nodules corresponds to extensive hemorrhage in the nodule and adjacent lung parenchyma. In these conditions, hemorrhage is regarded to be present owing to the fragility of the neovascular tissue with resultant thrombosis and rupture [4].
Pulmonary endometriosis with catamenial hemorrhage is characterized by recurrent hemoptysis occurring within 24Ð48 h after the start of each menstruation cycle in female patients in the reproductive age. Hemoptysis is usually small in amount and lasts a few days. It is frequently accompanied by cough and chest discomfort. The history of the obstetric procedure, especially induced abortion, is common [13].
Patient Prognosis
Advanced stage of the malignancy makes the prognosis very grave.
Pulmonary Endometriosis with Catamenial Hemorrhage
Pathology and Pathogenesis
The heterotopic tissue consists of both stroma and glands and reproduces the appearances of normal endometrium in every way (Fig. 6.5). Decidual change takes place in pregnancy, and cyclic hemorrhagic disruption, with consequent hemosiderosis, may obscure the nature of the tissue, in which case immunocytochemistry may be used to demonstrate estrogen and progesterone receptors and in the stromal component CD10 [12].
CT Findings
During menstruation, focal consolidation with a relatively well-deÞned margin and ground-glass opacity are common CT Þndings of pulmonary parenchymal endometriosis (Fig. 6.5) [3, 4]. However, CT scans obtained after menstruation demonstrate marked improvement of pulmonary consolidation and nodules. Other Þndings of thoracic endometriosis include thin-walled cavities or bullous formation and catamenial hemothorax or pneumothorax.
CT–Pathology Comparisons
CT Þndings of consolidation, nodules, and ground-glass opacity in pulmonary endometriosis can be presumed to represent pulmonary hemorrhage. Hemorrhage could result from the rupture of the capillaries in the endometrial tissue particles trapped within pulmonary vascular network [3, 4].

Pulmonary Endometriosis with Catamenial Hemorrhage |
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Patient Prognosis
When the site of pulmonary endometriosis is conÞrmed by chest CT to be localized and Þxed, surgical resection can be tried.
a
b
Medical treatment with progestational agents or gonadotropinreleasing hormones may be applied if hemoptysis continues with conservative therapy. Variable results in terms of shortand long-term outcome have been reported [14].
c
Fig. 6.5 Pulmonary endometriosis showing halo sign in a 46-year-old woman. (a, b) Lung window of consecutive CT scans (2.5-mm section thickness) obtained at levels of liver dome shows a cystic lesion (arrow) of eccentric wall thickness depicting surrounding ground-glass opacity halo in the right lung base. (c) Coronal reformatted (2.0-mm section thickness) image demonstrates cystic lesion with halo sign (arrow). (d)
High-magniÞcation (×100) photomicrograph of pathologic specimen obtained from the right lower lobe with wedge resection by using videoassisted thoracoscopic surgery discloses a nodule composed of many well-formed endometrial glands and admixed stroma. Also note a large dilated gland-forming cyst within central portion of nodule. Inset: stroma is pale pink and is composed of bland-looking oval or spindle cells (×200)