Outcome of keratolimbal allograft transplantation with deep anterior lamellar keratoplasty for bilateral limbal stem cell deficiency

Abstract

Objectives: To evaluate and compare the outcome of keratolimbal allograft (KLAL) transplantation with or without deep anterior lamellar keratoplasty (DALK) for bilateral severe limbal stem cell deficiency (LSCD).

Methods: This retrospective review included 49 eyes of 46 patients who underwent KLAL transplantation at the Department of Ophthalmology of Chinese PLA general hospital, 2009-2020, for bilateral severe LSCD were examined for corneal clarity and corneal scarring to determine whether to combine DALK with KLAL transplantation. Preoperative information, surgical decision tree, surgical procedures, and postoperative data were collected for each eye.

Results: All patients had preoperative severe or total LSCD. Twenty-four eyes underwent KLAL transplantation only, 25 KLAL transplantation plus DALK. The mean follow-up was 46.80 ± 31.22 months (18-158 months). Overall KLAL survival (with or without DALK) was 71.43% at the final follow-up (KLAL-only 66.67%, KLAL-DALK 76%). Kaplan-Meier survival analysis showed that the 3-year survival probability of all grafts was 70.53 ± 10.89% (KLAL-only 64.86 ± 10.11%, KLAL-DALK 75.79 ± 8.62%). The proportion of BCVA ≥ 20/200 eyes among all KLAL transplantations increased from 11 eyes (22.45%) preoperatively to 25 eyes (51.02%) after 1 year and 24 eyes (48.98%) at the last follow-up (P = 0.01). The proportion of BCVA ≥ 20/200 eyes in the KLAL-DALK group increased significantly (P = 0.04), from 16.0% at baseline to 48.0% after 1 year to 44.0% at the last follow-up. Seventeen eyes (34.69%) had postoperative complications.

Conclusion: KLAL-DALK is an effective option to restore a stable ocular surface and visual acuity rapidly in patients with bilateral, late-stage, severe LSCD.

Keywords: cornea; deep anterior lamellar keratoplasty; keratolimbal allograft; limbal stem cell deficiency; limbus; survival analysis; visual acuity.

FIGURE 1

(A) Postoperative outcomes of KLAL transplantation in patients with severe bilateral limbal stem cell deficiency caused by chemical burns. Clinical photographs of the right eye of a 57-year-old male before KLAL-only transplantation (a), 12 months after KLAL-only transplantation (b) and the left eye of a 40-year-old female before KLAL transplantation combined with DALK (KLAL-DALK) (c), 12 months after KLAL-DALK (d). (B,C) The positioning of the graft in relation to angle structures. Keratolimbal allograft transplantation (B). Keratolimbal allograft transplantation combined with deep anterior lamellar keratoplasty (C). KLAL, keratolimbal allograft; DALK, deep anterior lamellar keratoplasty.

FIGURE 2

Kaplan–Meier survival analysis of graft survival with a stable corneal surface after KLAL transplantation. Survival analysis of grafts for all treated eyes (n = 14). Three years after surgery, 71.43% of eyes had a stable and improved corneal surface (A). Grafts in eyes that underwent KLAL transplantation only (n = 24) had a similar survival curve as grafts in eyes that underwent KLAL transplantation with DALK (n = 25). Three years after surgery, the corneal surface was stable in 66.7% of eyes in the KLAL-only group and 76% of eyes in the KLAL-DALK group (B). Survival analysis of grafts on the basis of preoperative etiology (C), whether ocular surface reconstruction (D) was performed before KLAL transplantation, which showed no significant difference (log-rank test, P > 0.05). KLAL, keratolimbal allograft; DALK, deep anterior lamellar keratoplasty; LSCD, limbal stem cell deficiency.

FIGURE 3

BCVA preoperatively and at the 1-year and final follow-up after KLAL transplantation in all eyes. In the whole patient cohort (n = 49), the BCVA at 1 year postoperation (P = 0.002) and at the final follow-up (P = 0.01) was significantly improved compared with that preoperation (A). For the KLAL-only group (n = 24), the BCVA improved postoperatively but was not significantly different from that preoperatively (P = 0.06, 0.17) (B). For the KLAL-DALK group (n = 25), the BCVA at 1 year postoperation (P = 0.02) and at the final follow-up (P = 0.03) was significantly improved compared with that preoperation (C). The number of eyes with a BCVA ≥ 20/200 preoperatively, postoperatively, 1 year postoperatively and at the final follow-up (D). Data are presented in dot plots including all individual points (*p < 0.05, **p < 0.01). A Wilcoxon matched-pairs signed rank test was used to compare the postoperative and preoperative BCVA values. BCVA, best corrected visual acuity; KLAL, keratolimbal allograft; DALK, deep anterior lamellar keratoplasty.