Effect of lyophilized amniotic membrane on the development of adhesions and fibrosis after extraocular muscle surgery in rabbits.

PURPOSE

To histopathologically evaluate the influence of lyophilized human amniotic membrane transplant on the development of postoperative adhesions and fibrosis after extraocular muscle surgery.

METHODS

Ten albino rabbits were used. The superior rectus muscle was resected 4 mm in both eyes. In right eyes, the superior rectus muscle was wrapped with lyophilized (air-dried, freeze-dried) human amniotic membrane (group AM). In left eyes, the superior rectus muscle was not wrapped with amniotic membrane, and served as a control group (group C). The rabbits were sacrificed and the eyes were enucleated 6 weeks after surgery to perform histopathological examination.

RESULTS

Two rabbits died 1 week after surgery and were excluded. Histopathological evaluation of both eyes of the remaining 8 rabbits was done. The amniotic membrane was not seen in all eyes. On comparing eye pairs of each rabbit, right eyes showed significantly less conjunctival inflammation (p = 0.034), but insignificantly less foreign body inflammation (p = 0.625), adhesions between sclera and muscle (p = 0.206), muscle fibrosis (p = 1.000), and conjunctival hyperemia (p = 0.059) as compared to left eyes.

CONCLUSIONS

Lyophilized amniotic membrane insignificantly reduces postoperative adhesions and fibrosis, when used to wrap the operated upon extraocular muscles, limiting the benefit of this membrane in strabismus surgery.