Radiologic and pathologic features of bronchiolitis.

Abstract

The purpose of this article is to describe and illustrate the clinical, pathologic, and imaging features of the inflammatory and fibrotic forms of bronchiolitis. The CT features presented in this article represent the typical features associated with each entity. Direct signs of bronchiolitis include centrilobular nodules and tree-in-bud pattern. Indirect signs include mosaic attenuation and air trapping. Although classic examples of each entity exist, there can be substantial overlap in the appearances, and distinguishing among these entities is not always possible. When high-resolution CT features overlap, clinical details will usually help to narrow the differential diagnosis.