A controlled study of the role of cryopreserved amniotic membrane transplant during strabismus reoperations

Purpose To evaluate the effects of using cryopreserved human amniotic membrane (AM) transplant during strabismus reoperations. Methods A total of 30 patients with persistent strabismus were included in this prospective study. Patients were divided into two groups of 15 patients each. The AM group underwent strabismus reoperation with wrapping of the muscles with cryopreserved amniotic membrane. Controls underwent strabismus reoperation without an AM wrap. Final follow-up visit was scheduled between 3 and 12 months postoperatively. Surgical success was defined as 0 Δ -10 Δ of horizontal tropia and 0 Δ -4 Δ of vertical tropia, with no limitation of ductions exceeding −1. A cosmetically acceptable outcome was defined as a tropia of 0 Δ -15 Δ . Results Three patients were excluded in the AM group due to incomplete follow-up. A successful outcome was achieved in 7 patients in each group (58% and 47% in groups AM and C, resp.; P  = 0.63). A cosmetically acceptable outcome was achieved in 10 patients in the AM group (83.3%) and 12 (80%) in the control group ( P  = 0.48). The mean ocular deviation angles improved to 8.7 Δ ± 12 Δ in the AM group and 12.3 Δ ± 17.4 Δ in the control group ( P  = 0.63). Ductions improved in 66.7% and 36.4% of the muscles with limited motility in groups AM and C, respectively ( P  = 0.019). Conclusions Wrapping the extraocular muscles with cryopreserved AM during strabismus reoperations was of limited clinical benefit. We attributed this to the small segment of AM used and to the presence of other causes of failure rather than adhesions.