Single versus Double Layer Amniotic Membrane Transplantation in Management of Resistant Infective Corneal Ulcer

Background: Infectious keratitis is an important and preventable cause of monocular blindness. It is caused by bacteria, fungi, viruses, or parasites, It is a potentially sight-threatening disease of the eye as a result of corneal opacities, persistent epithelial defects, thinning or corneal melting.2

This urgent ophthalmic condition needs to be treated with appropriate antimicrobial agents. However, some ulcers do not respond to conventional antimicrobial treatments and need further intervention 4.

Amniotic membrane transplantation (AMT) may be a tool to suppress inflammation in infectious keratitis and promote epithelial regeneration after sufficient antibiotic eye medications, thus improving the situation of the eye for subsequent surgeries, such as penetrating keratoplasty (PK).2

Aim of the Study: This prospective, comparative, interventional and randomized study aimed to compare efficacy and safety of single versus double layer amniotic membrane transplantation (AMT) in treatment of resistant infectious keratitis.

Patients and Methods: The study was carried out on 40 eyes with resistant infectious keratitis not respond to specific antimicrobials for two weeks (20 eyes treated by single layer of amniotic membrane (group A) and 20 eyes treated by double layer amniotic membrane (group B) .

Results: The mean age of group (A) was (54.250 ± 12.561) years while in group (B) was (52.250 ± 14.722) years. The gender distribution of group (A) was 13 male and 7 female , group (B) was 14 male and 6 female .According to corneal cultures there were 6 cases (30%) fungal , 3 cases (15%) bacterial and 11 cases (55%) mixed bacterial and fungal infection in group (A),While in group (B) there were 7 cases (35%) fungal and 13 cases (65%) mixed bacterial and fungal infection. The healing time ranged from 3 to 8 weeks with mean 5.214 ± 1.888 weeks in group (A), While in group (B) ranged from 3 to 6 weeks with mean 4.412 ± 0.712 weeks. The study revealed no significant difference in pre-operative and post-operative best correctd visual acuity in both groups as in group A vision improved in 5 cases , remain unchanged in 9 cases and worsened in 6 cases while in group B vision improved in 5 cases, remain unchanged in 12 cases, and worsened in 3 cases. There was significant difference between two groups in healing of sever corneal ulcer as in group A all cases with sever corneal ulcer not achieve successful healing , While in group B successful healing occurred in 83.33% of sever cases.

Conclusion: There is no significant difference between single layer and double layer AMT in management of resistant infectious keratitis especially mild and moderate corneal ulcers .

In sever corneal ulcer it is better to do double layer AMT to restore integrity of corneal stroma and promote healing.