Ligne De Kerley -

Atelectasis (which is denser/lobar) or vessels (which branch).

Here’s a social media post (Instagram/Caption style) explaining for a medical audience (students, residents, or radiology techs). 🩻 Chest X-Ray Spot Diagnosis: Kerley B Lines ligne de kerley

When you see these fine, horizontal lines at the lung bases—especially in the costophrenic angles—you're looking at . 📍 ligne de kerley