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 Consolidation

Radiological Characteristics

• Opacification
• Lobar/Segmental distribution
• Air bronchogram
• No significant loss of lung volume

Etiology

• Streptococcus
• Legionella
• Mycoplasma
• Post obstructive

Atelectasis

Radiological Characteristics

1. Opacity (airless lung)
2. Signs of loss of lung volume.          

• Mediastinal shift
• Elevated diaphragm
• Movement of fissures
• Shift of hilum
• Change of proportion of lungs
• Smaller hemi thorax

       3. Compensatory hyperinflation

Etiology

• Cancer
• Foreign body
• Benign tumor
• Granuloma

Pneumothorax

Radiological Characteristics

• Dark  field with no vascular markings in the pleural space
• Visible collapsed lung 
• Larger hemi thorax

Etiology

All Lung Diseases

Trauma

• Procedures
• Accident
• Barotrauma (Ventilator)

"Normal Lungs"

• Bullous lesions
• Marfan's syndrome
• Ehler Danlos syndrome
• Catamenial Pneumothorax (Endometriosis)
• In association with Mitral valve prolapse

Lung Mass

• Radiological Characteristics

  • Homogenous liquid density

  • Density >5 CMS in diameter  (less than 5 cm is called solitary pulmonary nodule)

  • Sharp margins

  • No respect for segments or fissures

• Etiology

  • Lung cancer

  • Granulomatous infections (TB, Histo, Blastomycosis)

  • Wegners Granuloma

  • Rheumatoid lung

  • Metastasis

Pleural effusion

Radiological Characteristics

• Loss of costophrenic angle
• Loss of diaphragmatic shadow
• Homogenous opacification
• Shift of mediastinum to opposite side with large effusions
• Ellis line (Meniscus high in axilla)
• In base in upright film

Etiology (common diseases)

• Congestive heart failure
• Cancer
• Tuberculosis
• Parapneumonic effusions
• Empyema
• Hemothorax
• Rheumatoid arthritis

Cavity

Radiological Characteristics

• Number ( single or multiple)
• Size
• Site (apices of lobes for TB, classical segments for aspiration)
• Thickness of wall (thick, thin)
• Content (fluid level, fungous ball)
• Lumen (irregular)
• Associated findings

Etiology

• Lung cancer  :  Squamous cell Cancer Lung (Thick wall, Irregular lumen, Stalactites and Stalagmites) 
• Metastasis
• Wegners Granuloma
• Rheumatoid lung
• Cystic fibrosis
• Granulomatous infections TB, Histo
• Lung abscess
• Necrotizing Pneumonia
• Coccidiomycosis
• Fungous ball (Mobile ball inside a cavity)

Congested lungs

In CHF radiological there is progression from

• Vascular congestion precedes congestion and can be recognized as prominent pulmonary veins. There will be cephalisation.
• In the next phase the interstitial edema and increased lymph flow manifests itself as Kerley lines.
• Next you see basal congestion with smaller lungs due to increased elastic recoil . Congested boggy Liver also pushes the diaphragm up.
• Full blown pulmonary edema is the last stage when you recognize acute diffuse alveolar pattern in CXR.

Chest wall lesion

Radiological Characteristics

• Peripheral density
• Sharp inner margin
• Indistinct outer margin
• Cat under the rug appearance with shallow concave edges.

Etiology

• Expanding rib lesions
  • Fracture with hematoma
  • Callus
  • Metastasis
  • Plasmacytoma
• Parietal pleural masses (Mesothelioma)
• Neurofibroma
• Plumbage

Solitary pulmonary nodule

Radiological criteria

• Liquid density
• Distinct margin
• Between 2-5 CMS in diameter
• Oval or round
• no other lesions

 Common lesions that can give you the Solitary pulmonary nodule

• Cancer
• Benign tumor
• Granulomas
• Round Pneumonia
• Rare but with characteristic features
• AV fistula
• Round Atelectasis
• Hydatid cyst
• Rheumatoid nodule

Lymphadenopathy

Radiological characteristics

• Widening of mediastinum
• Polycyclic margin
• Clear space between heart and the nodal density with Hilar nodes
• Extra pleural sign with Mediastinal nodes
• Obliteration of silhouette based on location
• Widening of Carina with subcarinal nodes

Common etiology

• Cancer Lung
• Lymphoma
• Granulomatous diseases
  • TB
  • Sarcoidosis
  • Histoplasmosis
  • Silicosis

Diffuse lung disease is categorized into

• Alveolar
• Interstitial
• Vascular

Most of the time it is mixed and difficult to categorize into one pattern.

Diffuse interstitial pattern

Radiological features

1. Lines (Kerley lines)
2. Nodules
3. Honeycombing

Common etiology

• Granulomatous disease
  • Miliary TB
  • Sarcoidosis
  • Silicosis
• Lymphangitic spread
• Idiopathic fibrosis
• Drug induced fibrosis
• Scleroderma

Diffuse alveolar pattern

Radiological Characteristics

• Soft fluffy lesions
• Coalescing lesions
• Air bronchogram
• Butterfly/Medullary distribution
• Cortical distribution
• Alveologram
• Segmental/Lobar density

Common causes of  Chronic alveolar infiltrates

• Alveolar proteinosis
• Alveolar form of Sarcoidosis
• Alveolar form of TB
• Alveolar form of Lymphoma
• Psudolymphoma
• Alveolar cell carcinoma
• Mineral oil aspiration
• Alveolar pattern of metastases
• Desquamative interstitial pneumonia
• Fungal infections

Mediastinal mass

Radiological criteria

Mass because

• Homogeneous liquid density
• Distinct margin

Mediastinal because

• Has Extra pleural sign (peripheral, absence of one of the margins both in PA and lateral view)
• Location is suggested by silhouette sign and lateral chest x-rays

Common Etiology

Anterior Mediastinum	Middle mediastinum	Posterior mediastinum
Thymoma Teratoma Thyroid Testicular metastasis Terrible lymphoma	Lymph node disease Bronchial Cysts	Neural lesions Esophageal disease Vertebral lesions

 

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