Authors (including presenting author) :
Yeung LMT (1), Li ALW (1), Ho VWM (1), Li KKW (1)
Affiliation :
Department of Ophthalmology, UCH
Introduction :
Amniotic membrane is a useful tool in surgical treatment of a wide variety of ophthalmology diseases. Kowloon East Cluster has harvested amniotic membranes following a stringent protocol in the past years.
Objectives :
In this study we review the procurement process, indications and outcomes of preserved amniotic membrane transplant (AMT) use in the past ten years in Kowloon East Cluster.
Methodology :
This is a retrospective review of electronic records of patients who have received AMT in Kowloon East Cluster from January 2015 to January 2025. The Department of O&G has helped to select potential amniotic membrane donors and arranged for preoperative serological tests for detectable pathogens. The EARLE’s balanced salt solutions, a sterile solution containing antibiotics for rinsing the sample, were prepared by Pharmacy. The Department of Microbiology has worked to ensure timely culture results were available to allow new batch of amniotic membranes to be put into clinical use. Ophthalmology theatre nurses and Procurement team have helped to source and ship storage solutions (Dulbecco modified Eagle medium solution), nitrocellulose paper, and setting up the theatre for AM harvest (basins, suction machines, flat table tops, labeled specimen bottles etc) and transfer the fresh prepared samples to be stored in -80C. Ophthalmologists were to coordinate all of the above, take consent from the donor and perform harvesting within one morning session in the operating theatre. On the day of AM harvest, the placenta was transferred to the ophthalmic theatre for amniotic membrane extraction and processing. Placental swabs for cultures were taken before rinsing of the membranes. The amniotic membranes were then rinsed with antibiotic solutions and flattened on nitrocellulose papers. It was then cut into desired sizes and stored in specimen bottles with Dulbecco modified Eagle medium storage solutions. Storage solutions came in 3 bottles and samples of each were sent separately for culture for bacteria and fungus. Sterile gloves were changed meticulously after touching each of the solutions to ensure there was no cross contamination. Once the culture result came back negative, the new batch of amniotic membranes could be put into clinical use.
Result & Outcome :
In 10 years, amniotic membrane was harvested from 10 pregnant patients who received elective caesarean section surgery under spinal anaesthesia. 234 amniotic membrane transplants have been performed in the past ten years in our cluster. Indications for surgery include steven’s johnson’s syndrome, chemical injuries, corneal perforation, pterygium, conjunctival mass excision and macular hole. With our stringent workflow, we have identified microbiological contamination in one storage solution in 2017 in which 1/3 of the batch of amniotic membranes was discarded. With our careful planning, the remaining 2/3 were safe for clinical use and there was no need to harvest again that year. Collaboration between Departments of Ophthalmology, O&G, Microbiology, Pharmacy, Theatre nurses and Procurement team has ensured there was at least one amniotic membrane donor on harvest day, and all necessary solutions and equipment were ready to allow the harvest to happen smoothly. Our current harvest protocol can safeguard the sterility of our harvested amniotic membranes. This multidisciplinary teamwork has ensured amniotic membrane is available for clinical use in Kowloon East Cluster and this service has benefited hundreds of patients in the past ten years.
