Medial degeneration Aortic elastic fiber thinning 2018-10-14T14:57:36Z Aortic elastic fibre thinning A thinning out of elastic fibers of the media of the aorta that creates widening of intralamellar spaces, as identified on a stain for elastic fibers. A healthy aorta has dense elastic fibers comprising each lamella. This term describes the elastic network as being thinned at each lamella with narrower and more frayed apart elastic fibers. This entity may be associated with an increase in extracellular matrix material in the lamellar unit. The use of an elastic stain is essential to identify this lesion.