Processing and standardization for post-removal transport of freeze-dried and cryopreserved amniotic membrane in comparative studies for the treatment of ocular surface diseases.

Abstract

Ocular surface diseases (OSD) are one of the most frequent causes of visits to Ophthalmology outpatient clinics. They comprise a heterogeneous group of diseases that have in common the presence of at least one of the following pathophysiological characteristics: change in the composition of the tear film, eyelid changes, destruction of limbal stem cells, inflammatory process and changes in corneal innervation. Examples of potentially serious OSD are: severe dry eye - which includes Stevens-Johnson syndrome (SJS), Sjögren's syndrome and Graft-versus-Host Disease (GVHD), chemical burns and neurotrophic keratitis. The treatment of OSD is still a major challenge. The therapeutic modalities routinely used in clinical practice allow for inflammatory control and supplementation of the tear film, in an attempt to improve healing and patient comfort. However, there are several limitations and associated side effects.The Amniotic Membrane (AM), the inner part of the fetal membranes, is increasingly used for reconstruction of the ocular surface in various ophthalmic diseases. In order to obtain it, the collection of the appropriate placenta, the meticulous preparation and the storage of the amniotic membrane in certified tissue establishments are crucial processes that allow the maintenance of the therapeutic properties of AM necessary for its application in DSO. Among the preservation methods for storing human AM are cryopreservation and lyophilization. Comparative analysis of AM conservation forms, as well as studies on their applicability and effectiveness in DSO in the acute phase, such as chemical burns and Stevens Johnson Syndrome, will allow the expansion of techniques and new treatment protocols.