History of metaphoric signs in radiology

To survey the nearly 100 year history of metaphoric sign naming in radiology describing the pace of their overall accumulation in the radiology canon, their specific rates of growth by modality and subspecialty and the characteristics of the referents to which the signs are attached.

A comprehensive list of metaphoric signs was compiled from a search of articles in several major English language radiology journals, from a roster compiled in a monograph on the subject published in 1984 and from a search of several databases to find signs published in the first half of the 20th century.

The growth of radiological metaphorical signs naming was slow for several decades after the first one was published in 1918. It then increased rapidly until the 1980s encompassing all modalities and subspecialties. Recently the practice has shown a marked and steady decline.

Metaphoric sign naming was a frequently reported contribution to the radiological literature in the second half of the 20th century corresponding with Radiology's growth as a descriptive discipline. Its decline since then may be a consequence of Radiology's evolution into a more analytic, data-driven field of inquiry.