B-lines

B-lines are vertical, bright lines seen on lung ultrasound images that extend from the surface of the lung slab downward without fading. They indicate that the lung tissue has increased fluid or thickening in the spaces between its air sacs, often associated with conditions like pulmonary edema or fibrosis. B-lines help doctors assess the presence and severity of lung congestion or fluid buildup, providing a quick and non-invasive way to evaluate lung health. They are an important diagnostic feature in lung ultrasound, offering insights into fluid accumulation that might not be visible on a regular chest X-ray.