"The mistletoe sign refers to solid enhancing perivascular masses around the coronary arteries in the presence of idiopathic retroperitoneal fibrosis (Ormond's disease).The presence of the mistletoe sign on cardiac MRI and coronary CT angiography is relatively rare, but it might be a characteristic manifestation of retroperitoneal fibrosis. With the increasing number of non-invasive cardiac imaging tests performed worldwide, the recognition of this imaging sign could aid the diagnosis of retroperitoneal fibrosis."
"History and etymology"