Chang sign (pulmonary embolism)
The Chang sign refers to the dilatation and abrupt change in caliber of the main pulmonary artery due to pulmonary embolism . It is one of several described signs of pulmonary embolus on chest radiographs.
History and etymology
It is named after C H Joseph Chang, (July 7 1929 - November 15 2017) an American radiologist, who first described it in 1965 .