Kerley’s B lines are not vessels or scars. They represent —the fibrous boundaries between the lung’s secondary lobules. Normally invisible on X-ray, they become visible when fluid accumulates in the interstitial space of the lungs.
Kerley's B lines are often seen in conjunction with other radiographic findings, such as: kerley's b lines
Named after the Irish radiologist Dr. Peter Kerley (1900–1979), these lines were first described in the 1930s. Kerley, working at the National Heart Hospital in London, noticed them in patients with mitral stenosis. He classified three types (A, B, C), but B lines became the star—easily spotted and clinically useful. Kerley’s B lines are not vessels or scars
The spread of cancer (such as lung, breast, or stomach) through the lymphatic system can cause persistent septal thickening. Kerley's B lines are often seen in conjunction
lines:
Think of the lung as a sponge. The alveoli (air sacs) are the holes; the connective tissue around them is the sponge’s framework. When left atrial pressure rises—due to heart failure, mitral disease, or fluid overload—fluid first leaks into this interstitial space, not yet into the alveoli. This is .
They do not branch or taper like blood vessels. Instead, they stop abruptly at the visceral pleura—like tiny railroad ties running toward the chest wall.