Purpose:
This study aims to report the long-term survival of corneal allografts in eyes undergoing autologus cultivated limbal epithelial transplantation (CLET) and penetrating keratoplasty (PK).
Methods:
This was a retrospective interventional case series that included 43 eyes of 43 patients with unilateral limbal stem cell deficiency (LSCD) due to ocular burns; 10 eyes underwent simultaneous (single-stage) and 33 eyes underwent consecutive (two-stage with minimum interval of 6 weeks) autologous CLET and PK. The medical record of each patient was reviewed for demographics, primary etiology, previous surgical procedures, preoperative and postoperative best corrected visual acuity (BCVA), clinical findings and complications. The primary outcome measure was corneal allograft failure, defined clinically as irreversible loss of central graft clarity. The survival of the corneal allograft was estimated using Kaplan Meier survival analysis. Risk factors of graft failure were analyzed using Cox proportional hazards model. The secondary outcome measures were post-operative best corrected visual acuity (BCVA) and complications.
Results:
Most patients were young (median age: 18 years) males (76%) with LSCD due to alkali burns (79%) and a mean follow-up of 4.38 ± 1.84 (range 1 to 8) years. The overall corneal allograft survival was 55.81 ± 7.57% at 1 year (median survival of 2.5 years); the corneal allograft survival after two-stage CLET and PK was 66.67 ± 8.13% at 1 year (median survival of 3.3 years). Single-stage CLET and PK had a greater risk of both corneal allograft failure (hazards ratio 4.5, P=0.006) and recurrence of LSCD (60%, P= 0.02), as compared to two-stage surgery. Failure occurred in 25 eyes due to graft rejection (36%), graft infiltrate (28%), recurrence of LSCD (8%) or combination of causes (28%). One third of the eyes achieved a BCVA of 20/60 or better. The commonest cause for low vision in spite of a clear graft was amblyopia.
Conclusions:
The risk of corneal allograft failure in these eyes is high and survival decreases with time; avoiding simultaneous limbal and corneal transplantation and adopting measures to prevent the causes of corneal allograft failure are needed to improve outcomes.
Keywords: transplantation • cornea: clinical science