Left lower lobe atelectasis - There is a triangular density seen through the cardiac shadow. This must be an abnormality located posterior to the heart. This is confirmed on the lateral view. The contour of the left diaphragm is lost when you go from anterior to posterior. As the title suggests this is lower lobe atelectasis. We cannot see the lower lobe vessels, because they are surrounded by the atelectatic lobe. Normally when you follow the thoracic spine form top to bottom, the lower region becomes less opaque. Here we have the opposite #Clinical #Radiology #CXR #LLL #Lobar #Collapse #RadiologyAssistant
