Diffuse cystic lung disease at high-resolution CT.

OBJECTIVE This article will illustrate and describe the spectrum of diseases associated with air cysts at high-resolution CT (HRCT). CONCLUSION HRCT is an important modality in the evaluation of interstitial lung disease to include cystic lung disease. Although most commonly associated with lymphangioleiomyomatosis or Langerhans cell histiocytosis, cystic lung disease is increasingly being recognized as a feature of other entities. Awareness of the spectrum of HRCT findings associated with these diseases may help the trained observer narrow the differential diagnosis.