What Is Kerley B | Lines

Let’s break that down. The lungs are divided into tiny lobules, like a honeycomb. Each lobule is surrounded by connective tissue called the . Inside these septa run small veins and lymphatic channels. When the pressure in the left side of the heart rises (e.g., due to CHF or mitral valve disease), that pressure backs up into the pulmonary veins. This increases capillary hydrostatic pressure, forcing fluid out of the capillaries and into the interstitial space. The interlobular septa become fluid-logged—swollen, thickened, and more opaque to X-rays. When you see a Kerley B line, you are literally seeing a cross-section of a waterlogged "wall" between lung lobules.

for clinical utility, elegance, and teaching value. Kerley B lines are a perfect example of why the physical exam and basic imaging still matter in a high-tech world. Next time you see them, tip your hat to Dr. Kerley—then reach for the furosemide. what is kerley b lines

Highly specific for interstitial edema, easy to learn, rapid to identify, and historically rich. Weaknesses: Requires good X-ray quality (underpenetrated or overpenetrated films hide them). Can be mimicked by lymphangitic cancer. Not visible in supine patients (where fluid distributes posteriorly, not basally). Who should learn this? Every medical student, resident in internal medicine, emergency physician, intensivist, radiologist, and family doctor. Even paramedics and nurses in critical care will benefit from recognizing these lines on portable CXRs. Let’s break that down