Effect of cryopreserved amniotic membrane on the development of adhesions and fibrosis after extraocular muscle surgery in rabbits.
OBJECTIVE
To histopathologically evaluate the effect of cryopreserved human amniotic membrane (AM) transplant on preventing the development of postoperative adhesions after extraocular muscle surgery.


METHODS
Ten albino rabbits were used. The superior rectus muscles were bilaterally resected. In right eyes, the muscle was wrapped with cryopreserved human AM (group AM). In left eyes, the muscle was not wrapped with AM and served as a control group (group C). The rabbits were killed, and the eyes were enucleated 6 weeks after surgery to perform histopathological examination.


RESULTS
On histopathological examination, the AM was present in eight eyes, surrounded by periamniotic inflammation, with no adhesions detected between rectus muscle and sclera, conjunctiva and Tenon's capsule in the segment where the AM was present, but detected elsewhere. Adhesions were detected in the other two eyes of group AM, in which the AM was absent, and in all group C eyes. When comparing eye pairs of each rabbit, AM eyes showed significantly less adhesions between the muscle and sclera (p = 0.009) and between the muscle and Tenon's capsule and conjunctiva (p = 0.008), in the region of AM application, and significantly more foreign body inflammation (p = 0.031), than C eyes. The differences between AM and C eye pairs, in terms of conjunctival inflammation and vascularity and muscle fibrosis, were insignificant (p > 0.05).


CONCLUSIONS
Cryopreserved AM is effective in reducing postoperative extraocular muscle adhesions. Its application is, therefore, recommended during strabismus reoperations.
Ophthalmology Department, Cairo University, Egypt Pathology Department, Cairo University, Egypt. rehabrkassem@hotmail.com
Rehab R
RR
Kassem
Mostafa M
MM
Khodeir
Mostafa
M
Salem
Mohammed A
MA
Abdel-Hamid
Randa M Abdel-Moneim
RM
El-Mofty
Ahmed M
AM
Kamal
Hala M
HM
Elhilali
D000650:Amnion / Q000637:transplantation*; D000818:Animals; D015925:Cryopreservation; D005355:Fibrosis / Q000517:prevention & control; D006801:Humans; D009801:Oculomotor Muscles / Q000473:pathology / Q000601:surgery*; D011183:Postoperative Complications / Q000517:prevention & control*; D011817:Rabbits; D013285:Strabismus / Q000601:surgery; D000267:Tissue Adhesions / Q000209:etiology / Q000517:prevention & control*; D014021:Tissue Preservation; D014183:Transplantation, Heterologous; D014945:Wound Healing / Q000502:physiology