Kerley A Vs B: Lines

Kerley lines are a crucial radiological finding in chest X-rays, particularly in the diagnosis of heart failure and other pulmonary conditions. These lines represent interstitial edema and are a key indicator of fluid overload in the lungs. There are two types of Kerley lines: Kerley A lines and Kerley B lines. Understanding the differences between them can help in making accurate diagnoses and guiding treatment.

| Feature | Kerley A Lines | Kerley B Lines | |---------|---------------|----------------| | | “Butterfly” or “apical” lines | “Septal” lines | | Length | 2–6 cm | 1–2 cm | | Shape | Long, unbranched, straight | Short, horizontal, parallel | | Location | Central → upper/mid zones, pointing toward hilum | Peripheral → lung bases, especially costophrenic angles | | Orientation | Radiating from hilum | Perpendicular to pleura (horizontal) | | Width | ~0.5–1 mm | ~0.5–1 mm | | Histology | Fluid in deep interlobular septa (anastomosing lymphatics) | Fluid in peripheral interlobular septa | | Clinical note | Less common; often indicates more acute or severe edema | Most common septal line; earliest sign of interstitial edema | kerley a vs b lines