Fig. 2

Histopathological findings (a-c) and immunoreactivity for Ki67 (d-f) in the excised pterygium-like tissue. a The head of the excised tissue was covered by stratified squamous metaplasia (yellow circle). Dense collagenous tissue was located beneath the epithelium (white arrows), where a collection of degenerated elastic fibers (white circle) was intermingled. Some goblet cells were contained in the epithelium (insert). A bar indicated 50 μm. Hematoxylin and eosin (H&E) stain. b The body of the excised tissue was rich in dilated blood vessels (white asterisks). A peripheral nerve was found in the subepithelial stroma (yellow arrows). H&E stain. c The body of the excised tissue also contained mature adipose cells (black asterisks) and collagen fibers in the subepithelial stroma. H&E stain. d A number of Ki67-immunopositive cells were located in the pterygial epithelium (yellow arrows). A bar indicated 50 μm. e Ki67 was immunoreactive in several endothelial cells in the neovessels (yellow arrows) but not in the peripheral nerve (asterisks). A bar indicated 50 μm. f Immunoreactivity for Ki67 was not detected in the adipose and collagen tissues