The diaphragmatic margin sign is a small triangular abnormality that obscures the normal shape of the diaphragm. It is secondary to atelectasis in the upper lobe. It is caused by traction on the pleura or the greater interlobar fissure and the subpleural ligament.

Can we use chest radiographs to identify underlying coronary artery disease? According to a study published in the journal Cardiothoracic Imaging, artificial intelligence (AI) can identify this.