What is sub pleural reticulation?

Reticulation refers to a pattern seen on a chest x-ray or lung CT scan. A reticular pattern means there is thickening of some of the lung tissues that surround the alveoli (air sacs) in the lungs. The thickening can be due to fluid accumulation, inflammation or scarring. Subpleural reticulation means the thickening is located in outermost part of the lungs. It is usually seen in people with interstitial lung disease.