hilum convergence sign

The hilum convergence sign is a useful chest radiograph sign to distinguish the cause of a bulky hilum as due to pulmonary artery dilatation or to a juxtahilar mass, including nodal enlargement.

If pulmonary vessels appear to converge centrally towards the lateral margin of the abnormal 'bump', then the hilar opacity is an enlarged pulmonary artery .

If vessels do not converge towards the opacity and instead converge more towards the waist of the heart, then the opacity is due to a hilar/mediastinal mass. The converging vessels can be traced through the opacity, indicating the related hilum overlay sign.

Terminology

Authors differ as to which of the aforementioned findings constitutes a 'positive' or 'negative' hilum convergence sign. Some write that the hilum convergence sign refers to the convergence of vessels onto the opacity, consistent with vascular dilatation, whereas vessels would not converge into a hilar mass . Others state the opposite: hilum convergence sign refers to vessels converging towards the waist of the heart, indicating a hilar mass . Others, following the original description, do not specify .

History and etymology

Benjamin Felson (1913-1988) was an American radiologist who first described this sign, initially called the hilus bifurcation sign .

Siehe auch:

• hilum overlay sign
• pulmonary artery dilatation