Electron Microscopic Evaluation of Intrastromal Corneal Rings Explanted From Nonfunctional Human Eyes

Intrastromal corneal rings (ICRs) often exhibit small deposits in association with their suture holes. We assessed the morphology of four such deposits.Four ICRs, explanted from nonfunctional human eyes, were examined by scanning electron microscopy and transmission electron microscopy.The surface of the suture hole deposits consisted of a disorganized convolution of collagenous lamellae. Within individual lamellae, however, the collagen fibrils tended to orientate parallel with one another. The deposits consisted of an amorphous material interspersed with curved cellular processes, collagen fibrils of variable diameter, and proteoglycan macromolecules.We propose that the mechanism which regulates stromal remodeling is amended in the region of the ICR suture holes. Due to their location, suture hole deposits have no optical significance; however, evaluation of their morphology provides insights into the wound-healing properties of the corneal stroma following ICR insertion.