The aortopulmonary window is an anatomical space located in the mediastinum, between the aortic arch and the pulmonary artery. The AP window is an important landmark which contains lymph nodes, nerves, and blood vessels. Lymph node enlargement in this region is often assessed in cases of cancer staging or for evaluating mediastinal masses.
Normal frontal CXR shows the location of the aortopulmonary (A-P) window (magnified in b and d – white arrowhead) and lying between the aortic knob above (d, green curve) and the pulmonary artery below (c and d yellow curve). The “curves” are often described as moguls of the left heart border by creating an imaginary ski slope with the silhouette of each convex outward left sided structure representing a mogul, and the left ventricular silhouette representing the final mogul free ski slope
Ashley Davidoff MD TheCommonVein.net 33679c