For patients with severe cases of limbal stem cell deficiency who need to undergo ocular surface stem cell transplants, living-related conjunctival limbal allograft (lr-CLAL) may have better outcomes—including decreased rejection rates—compared with keratolimbal allograft (KLAL), according to a new study in Cornea. The investigation also found lr-CLAL showed improved graft survival and better best-corrected visual acuity (BCVA) results than KLAL.

Historically, the KLAL procedure has been favored worldwide because it does not rely on a living donor, may be easier for surgeons and doesn’t burden the recipient’s family during the donor selection process, the researchers noted. “Despite the additional time and resources that may be necessary for successful lr-CLAL, we suspected that lr-CLAL had better outcomes,” the researchers wrote in their paper.

The study enrolled patients with bilateral total limbal stem cell deficiency who underwent surgical treatment with either a KLAL or lr-CLAL procedure. Participants also received systemic immunosuppression.

The study’s main outcome measures were ocular surface stability, BCVA and postoperative complications at the last follow-up.

The investigation included 224 KLAL eyes and 63 lr-CLAL eyes with an approximate follow-up of about seven years. For lr-CLAL eyes, 82.5% maintained a stable ocular surface compared with 64.7% of KLAL eyes at the last follow-up. Only 6.3% of lr-CLAL eyes showed a failed ocular surface compared with 15.6% of KLAL eyes. The approximate BCVA was 20/158 for KLAL eyes compared with 20/100 for lr-CLAL eyes at the last follow-up.

A smaller proportion of lr-CLAL eyes (30.2% vs. 43.3%) developed an episode of acute rejection, and a higher proportion of these episodes resolved with treatment in the lr-CLAL group (79% compared with 53.6%).

lr-CLAL is the preferred choice of ocular surface stem cell transplantation if a compatible donor is available, the researchers said.  “We now make every effort to find a potential donor and take the time to educate both patient and family that lr-CLAL is the best procedure,” they wrote in their paper.

Both careful preoperative donor selection and triple-agent systemic immunosuppression are critical to optimize ocular surface stem cell transplant outcomes, they added.

Cheung AY, Eslani M, Kurji KH, et al. Long-term outcomes of living-related conjunctival limbal allograft compared with keratolimbal allograft in patients with limbal stem cell deficiency. Cornea. April 6, 2020. [Epub ahead of print].