They represent thickening of the interlobular septa due to fluid accumulation (interstitial pulmonary edema). Common etiologies include:
The presence of Kerley B lines is a hallmark of interstitial lung disease . In the acute setting, they are a strong indicator of pulmonary edema and are often accompanied by other signs such as cardiomegaly (enlarged heart), pleural effusions, and pulmonary vascular redistribution (cephalization). kerley b lines cxr
In a healthy state, these septa are invisible on a conventional chest radiograph. However, when the pulmonary capillary wedge pressure (PCWP) climbs to 20–25 mmHg , fluid spills out into the interstitium. They represent thickening of the interlobular septa due