<unk>  is an abnormality visible on a chest X-ray, that shows widening of the mediastinum which may mimic the appearance of a thoracic<unk>  aneurysm. With aging, the ascending portion of the thoracic aorta increases in length by approximately 12% per decade, whereas the diameter increases by just 3% per decade. This elongation causes the ascending aorta to appear as a vertical shadow on the left heart border.<unk>  is often associated with<unk>  calcification which implies<unk>  degeneration and hypertension.<unk> , though not serious, should be differentiated from the more severe dissection of the aorta.
Aortic unfolding
Overriding aorta
Notching of the ribs
Shunt 
Bio-secure bubble
Local gigantism
Grand Rounds
Venous translucence