Abstract
Benjamin Felson was one of America's most influential chest radiologists, whose work reshaped how physicians teach and interpret chest radiographs. Felson spent nearly the entirety of his 50-year academic career at the University of Cincinnati, where he trained generations of physicians in radiographic interpretation. Before the advent of CT scanning, Felson named and popularized anatomy-based diagnostic signs, including the silhouette sign and the air bronchogram sign, giving practitioners a systematic basis for localizing and interpreting chest disease. His textbook, Fundamentals of Chest Roentgenology (1960), remains in continuous publication more than six decades later. The journal he founded in 1966, Seminars in Roentgenology, established the single-topic issue format later adopted across clinical medicine. This review discusses the life of Benjamin Felson, his diagnostic contributions, and his lasting legacy in radiology.