Abstract
Purpose :
The conjunctival repair is a crucial part of ocular surface reconstruction. Due to limitations of currently used substitute tissues e.g. amniotic membrane (AM), there is a need for the development of new scaffolds of consistent quality for conjunctival reconstruction. This study explored the biocompatibility and surgical usability of plastic compressed collagen (PCC) as an alternative conjunctival substitute.
Methods :
PCC gels were produced by neutralizing and polymerization of rat tail collagen type I following plastic compression using RAFT absorbers. Conjunctival defects were trepanned in New Zealand White rabbits and grafted using PCC or AM or remained ungrafted (n=12 per group). Number of sutures, defect size, conjunctival hyperemia and fornix depth were assessed at day 0, 3, 10, 14 and 28. Granulocytic infiltration, epithelialization, goblet cell (GC) amount and collagen fiber alignment were examined histologically (Hematoxylin/Eosin; Periodic acid-Schiff/Alizarin reaction; Masson-Goldner Trichrome) after euthanasia at day 10 or 28 (n=6).
Results :
Suture-loss, defect size, hyperemia and fornix depth of the PCC group were not significant altered compared to AM at day 3, 10, 14 and 28. Histologically, granulocytic infiltration revealed mild inflammation at day 10 but did not differ between PCC and AM group at day 10 (PCC: 336.0±101.9 granulocytes per mm2; AM: 504.8±90.0 granulocytes per mm2, p=0.165) or day 28 (PCC: 27.3±5.9 granulocytes per mm2, AM: 29.71±14.72 granulocytes per mm2, p>0.99). PCC was well integrated into the recipient conjunctiva with partial epithelialization after 10 days (69.42±9.24%). After 28 days, all groups revealed a closed, multilayered epithelium with equal amount of GC (PCC: 11.06±0.77 GC/mm2; AM: 11.04±0.61 GC/mm2, control: 10.76±0.66 GC/mm2) and an underlying conjunctival stroma with randomly aligned collagen fibers and no indication for conjunctival scarring.
Conclusions :
PCC gels offer an easily available scaffold for conjunctival reconstruction which can be produced in a standardized fashion. The present study demonstrates a good surgical applicability and ocular surface biocompatibility of PCC gels with minor host reaction and no indication for a consecutive conjunctival scarring. However, future studies are necessary to further evaluate their use for fornix reconstruction.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.