Egg and banana sign (pulmonary hypertension)

The egg and banana sign is a sign for the diagnosis of pulmonary arterial hypertension (PAH) on axial CT/MR images. It refers to the appearance of the aortic arch (banana) next to a distorted main pulmonary artery (egg). Like an egg, the main pulmonary artery is preferentially dilated in the PA plane, taking on an oval-shape at the level of the aortic arch.

This sign has been described as having a high specificity and positive predictive value (PPV) for pulmonary arterial hypertension, especially when found in the setting of additional classic signs of pulmonary arterial hypertension , such as the carina crossover sign. Some have raised the concern that the high positive predictive value is a function of the subset of patients the sign was described in (patients undergoing right heart catheterization) and that the specificity and PPV of the sign would not be as high in a general population .