One major difference between Covid-19 and other inflammatory / infective diseases of the lungs is the presence of a vasculopathy / angiopathy. While there is still debate about the exact pathophysiology behind the vascular involvement, there are radiology signs that allow us to identify the presence of a vasculopathy.
Many patients show prominent / dilated proximal or intra-lesional vessels. This is perhaps the simplest sign of a vasculopathy, rarely seen outside of a Covid-19 situation.
Jin J and his colleagues have tried to describe some signs associated with the dilatation of intra-lesions vessels; the “dandelion” sign and the “feathery” sign, both of which are quite self-explanatory.