Kai Saukkonen1, Amita Sharma1, Eugene J Mark1. 1. From the Departments of Pulmonary and Critical Care (K.S.), Radiology (A.S.), and Pathology (E.J.M.), Massachusetts General Hospital, and the Departments of Pulmonary and Critical Care (K.S.), Radiology (A.S.), and Pathology (E.J.M.), Harvard Medical School - both in Boston.