Clinical and histochemical data are presented in the case of a young man who had bilateral "oily" globules that were centrally located in the superficial corneal stroma. There was no associated corneal disease; however, epithelial involvement was noted to occur after several years.
The material may have been a mixture of compounds but was basically protein, which appeared to be a product of degenerating corneal stroma itself and not an epithelial product as had been suggested in the past.
Christensen GR. Proteinaceous Corneal DegenerationA Histochemical Study. Arch Ophthalmol. 1973;89(1):30-32. doi:10.1001/archopht.1973.01000040032008