Implantation of PHEMA keratoprostheses after alkali burns in rabbit eyes.
OBJECTIVE
We have previously examined histologically the healing of a PHEMA core-and-skirt keratoprosthesis (the Chirila KPro) as a full-thickness implant in healthy animal corneas. The present study was carried out to determine whether a diseased cornea could also generate biocolonization of the skirt region of a KPro.


METHODS
Ten KPros were placed as full-thickness corneal implants under conjunctival flaps in 10 alkali-burned rabbit corneas. Histological findings at intervals from 2 weeks to 6 months postoperatively were compared with earlier findings in 10 rabbits that had received identical KPros without prior alkali injury.


RESULTS
Despite severe corneal injury and the reduced keratocyte population present, there were no clinically detected complications in 60%. Histological findings established that, compared with healthy host tissue, skirt biocolonization and KPro-cornea healing after an alkali burn were impaired, with evidence of epithelial downgrowth in 40%. One animal required euthanasia earlier than the planned end point, but no KPro extrusions occurred.


CONCLUSIONS
Biocolonization of a KPro skirt is reduced but not prevented in an alkali-induced corneal inflammation model. Although no extrusions occurred, close follow-up and anticollagenolytic medication would be required to minimize the complication rate.
Hicks
C R
CR
Lions Eye Institute, Nedlands, Western Australia, Australia.
Vijayasekaran
S
S
Chirila
T V
TV
Platten
S T
ST
Crawford
G J
GJ
Constable
I J
IJ
D000818:Animals; D001672:Biocompatible Materials; D002057:Burns, Chemical / Q000473:pathology / Q000601:surgery*; D002455:Cell Division; D003228:Conjunctiva / Q000601:surgery; D003315:Cornea / Q000473:pathology / Q000601:surgery*; D065306:Corneal Injuries; D005126:Eye Burns / Q000139:chemically induced* / Q000473:pathology / Q000601:surgery; D005500:Follow-Up Studies; D011102:Polyhydroxyethyl Methacrylate; D011474:Prosthesis Design; D019919:Prosthesis Implantation; D011817:Rabbits; D012972:Sodium Hydroxide / Q000009:adverse effects; D013524:Surgical Flaps; D014945:Wound Healing
D001672:Biocompatible Materials; D011102:Polyhydroxyethyl Methacrylate; D012972:Sodium Hydroxide