Electron microscopy (EM): Most prominent feature was the large number of slender long-spacing collagen fibers dividing the tissue in many compartments (A). Fibrous long-spacing collagen the period length of which was in the order of 200 nm in this case (B), is not described in the literature to be specific for any disease, but has been found in a variety of normal and pathological tissues. Well-formed desmosomes or Birbeck granules were not found in this case.
Schraven et al. Diagnostic Pathology 2011 6:94 doi:10.1186/1746-1596-6-94