Assessment of lungs, pleura and airways on chest x-ray (approach)

Described below are points on the systematic assessment of airways, lung parenchyma, pleura on CXRchest radiographs.

1. Pleura

• pneumothorax: visceral pleural line parallel to the thoracic cavity, the absence of lung markings (vessels)
  • views to exaggerate pneumothorax: erect CXR in full expiration, lateral decubitus with the suspect side up
  • on supine film: deep sulcus sign, sharply outlined diaphragm, hyperlucent upper abdomen
  • imposters: scapula margin, clothes, wrinkles, lines/tubing, bullous disease
  • management: < 2cm - observe, > 2cm - aspirate.
• haemo-pneumothorax: air-fluid level, no meniscus visible
• tension pneumothorax: ipsilateral diaphragm depressed, mediastinal contents pushed contralaterally
• pleural effusion: look for the meniscus sign. Collects in the costophrenic angles. If supine - veiling opacity. Empyema can organize into loculations
• apical pleural thickening: focal area of thickening over the apex, can be heavily calcified
• pleural plaques: similar to the density of bone. Common posteriorly & laterally & inferior 1/3 of the thorax. Metastasis - less dense than bone
• lung collapse: opacity with no air bronchograms, negative mass effect (displacement of fissure, hilum, mediastinum, elevation of hemidiaphragm, the decrease in spacing between the ribs)

Pathology:

• central bronchogenic carcinoma and lobar collapse: "golden sign of S"

2. Lung parenchyma

• lobar collapse: opacity with no air bronchogram, negative mass effect with shift of a lung fissure, hilum, hemidiaphragm
• lung collapse: opacity with whiteout, negative mass effect with mediastinal shift to the contralateral side
• increased interstitial marking vs. airspace opacification
• consolidation: alveolar pathology (cloud("cloud-like/cotton-candy" shadowing); no volume loss, air bronchogram, homogeneous airspace opacity. Clears by 6 weeks, if not suspect malignancy
• pulmonary oedema:increased interstitial opacities (toomarkings ("too many squiggly lines"); airspace opacification
• emphysema: 1. pulmonary hyperinflation, 2. narrowed mediastinum, 3. prominant pulmonary vessels, 4. Reduced peripheral pulmonary vessels, 5. distance to hila/base

Pathology:

• left ventricular failure: 1. increased interstitial marking, 2. Airspace opacification, 3. bilateral pleural effusions