What are the radiological features of pulmonary edema?

From the Guidelines

Pulmonary edema is characterized by several distinct radiological features, including Kerley B lines, peripheral interstitial infiltrate, and subpleural thickened septal lines on high-resolution CT scanning, which are critical for diagnosis and differentiation from other pulmonary conditions. When evaluating radiological features of pulmonary edema, it is essential to consider the findings from high-resolution CT scanning, as this modality provides the most detailed information about the lung parenchyma 1. The presence of Kerley B lines, which are short horizontal lines at the lung periphery, indicates interstitial fluid in the interlobular septa, a common finding in pulmonary edema 1. Other characteristic features include:

• Peripheral interstitial infiltrate on chest radiograph
• Subpleural thickened septal lines on high-resolution CT scanning
• Centrilobular ground-glass opacities, which contrast with the panlobular distribution found in other forms of pulmonary hypertension 1
• Mediastinal lymphadenopathy, which can be associated with pulmonary edema 1 These radiological features are crucial for diagnosing pulmonary edema and distinguishing it from other conditions, such as pulmonary hypertension, and can help guide treatment decisions. In clinical practice, the identification of these features can aid in the early detection and management of pulmonary edema, ultimately improving patient outcomes in terms of morbidity, mortality, and quality of life.

From the Research

Radiological Features of Pulmonary Edema

The radiological features of pulmonary edema can vary depending on the underlying cause. Some common features include:

• Septal lines and peribronchial cuffing, often seen in postobstructive pulmonary edema 2
• Central alveolar edema, which can occur in more severe cases of postobstructive pulmonary edema 2
• Sharply demarcated areas of increased ground-glass attenuation, typically seen in pulmonary edema with chronic pulmonary embolism 2
• Large pulmonary arteries, diffuse interstitial edema with numerous Kerley lines, peribronchial cuffing, and a dilated right ventricle, often associated with pulmonary edema with veno-occlusive disease 2
• Kerley lines, peribronchial cuffing, and patchy, perihilar alveolar areas of airspace consolidation, characteristic of stage 1 near drowning pulmonary edema 2

Classification of Pulmonary Edema

Pulmonary edema can be classified into different types, including:

• Increased hydrostatic pressure edema
• Permeability edema with diffuse alveolar damage (DAD)
• Permeability edema without DAD
• Mixed edema, where there is both an increase in hydrostatic pressure and membrane permeability 2, 3

Imaging Manifestations

The imaging manifestations of pulmonary edema can be assessed using various modalities, including:

• Ultrasonography, which can detect extravascular lung water and visualize B lines, often caused by cardiogenic or noncardiogenic pulmonary edema 4
• Radiography, which can show a range of features, including interstitial edema, alveolar edema, and airspace consolidation 2, 5, 3