Kerley B Lines Definition File

Narrowing of the heart valve causing chronic pressure.

Interestingly, Kerley B lines are often transient. When a patient receives successful diuretic treatment, the fluid drains from the septa, and the lines can disappear within hours or days. If the lines persist despite treatment, it may suggest chronic scarring or an alternative diagnosis like interstitial lung disease. Kerley B vs. Kerley A Lines

Here is an informative breakdown of what Kerley B lines are, what they look like, and what they signify for patient health. kerley b lines definition

The most common cause due to fluid backup.

The presence of Kerley B lines typically suggests that fluid, cells, or connective tissue have infiltrated the normally thin interlobular septa. Narrowing of the heart valve causing chronic pressure

: Short (1–2 cm), thin (

: Often referred to as "septal lines" or "septal thickening" on CT scans. Clinical Significance If the lines persist despite treatment, it may

Short, fine lines throughout the lungs that create a reticular or "spider-web" appearance. They are rarely seen and often considered a radiographic artifact of B lines. Diagnostic Approach

Perpendicular to the pleural surface (horizontal). Size: Usually 1–2 cm long and very thin (less than 1 mm). Position: They touch the edge of the rib cage (the pleura). Common Causes

are short, thin, horizontal linear opacities seen on a chest radiograph that indicate thickening of the interlobular septa in the lungs. They are the most common and clinically recognizable of the three types of Kerley lines (A, B, and C) and are considered a hallmark sign of pulmonary congestion. Key Characteristics

Under normal conditions, these septa are too thin to be seen on a standard X-ray. However, when the pulmonary capillary wedge pressure rises—typically above 17–20 mmHg—fluid leaks into these septal spaces. This expansion creates the distinct linear shadows known as Kerley B lines. Radiographic Characteristics