The surgical outcomes of limbal allograft transplantation in eyes having limbal stem cell deficiency

Purpose: To report the limbal allograft transplantation and penetrating keratoplasty (PK) results in limbal stem cell deficiency (LSCD)-developed eyes because of chemical or thermal injury. Methods: Medical records of 18 eyes of 14 patients who had undergone keratolimbal allograft (KLAL) or living-related conjunctival limbal allograft (lr-CLAL) with or without PK and followed up at least 1 year postoperatively were evaluated retrospectively. The preoperative LSCD grade was noted in all patients. Rejection incidents, recurrence of LSCD, and corneal graft clarity along with a visual improvement during the follow-up were noted. The complications rate due to surgery or injury itself, for instance, glaucoma and cataract, were evaluated. The limbal allograft tissue survival analysis and corneal allograft survival analysis were done to reveal the differences in both the procedures. The existence of normal corneal epithelium and improvement in visual acuity were accepted as the surgical success criteria. Results: In the limbal allograft transplantation group, the survival rates of the allograft tissue were 65 ± 10.7% at 1 year and 36.6 ± 11.4% at 3 years in lr-CLAL and 66.7 ± 15.7% at 12 months and 53.3 ± 17.3% at 18 months in KLAL-transplanted eyes. The survival rate of corneal allograft at the 5 postoperative year was lower in the simultaneous procedure compared to the staged procedure, but it was not statistically significant (25.7 ± 25.8% vs. 62.5 ± 17.1%, P = 0.75). The ambulatory vision was achieved in 10 eyes (56%) after a mean follow-up time of 93.8 ± 37.8 months. The visual acuity level has increased in 12 eyes (67%) in which the limbal allograft transplantation was applied. The ambulatory visual acuity level was achieved (≤1.0 logMar [20/200]) in 10 eyes (56%). In addition, two or more Snellen lines' gain in the best corrected visual acuity was observed in 12 eyes of 18 (67%) at the last follow-up, and there was not any significant difference between the KLAL and lr-CLAL. Conclusions: Ocular surface integrity was longer in KLAL than in lr-CLAL transplantation, but it was not statistically significant. The staged procedure was more convenient than the simultaneous procedure in terms of corneal allograft clarity maintenance in limbal allograft-employed eyes.