Long-term Clinical Course of Amniotic Membrane after Permanent Amniotic Membrane Transplantation

Abstract

Purpose: To investigate the long-term clinical outcomes of transplanted amniotic membrane in patients who underwent permanent amniotic membrane transplantation (P-AMT) on cornea.Methods: From April 2014 to March 2021, medical records and digital photographs of 68 patients (72 eyes) who underwent P-AMT were analyzed retrospectively. The duration of complete re-epithelization of cornea and wearing therapeutic contact lense (T-lens) after surgery were investigated, the size of preserved amniotic membrane (AM) excluding the melted portion was analyzed using the Image J program every year up to 6 years after surgery, and it was compared by dividing into a single-layer group and a double-layer group. In addition, when the AM melts, the cause, time, and related factors of melting were analyzed.Results: The average duration to complete re-epithelialization after surgery was 12.2 ± 11.0 days, and T-lens were worn on average up to 8.7 ± 8.5 months after surgery. In total group, the average ratio of preserved AM annually up to 6 years after surgery was 94.9%, 94.3%, 97.8%, 96.4%, 95.8%, 91.6% respectively, and there was no significant difference between the single-layer group and the double-layer group. AM melting appeared in 38.9% (28 eyes) of the total group, and melting was first observed on average 16.4 ± 17.2 months after surgery. The formation and rupture of bullae was the most common cause of melting at 71.4% (20 eyes), and there were no statistically significant related factors involved in the formation of bullae.Conclusions: In the case of P-AMT performed in various diseases of the cornea, the transplanted AM is partially melt but considered to be well preserved up to 6 years after surgery to form a stable ocular surface.