Scientific and Clinical Support for the Use of Dehydrated Amniotic Membrane in Wound Management

Donald E. Fetterolf, MD; and Robert J. Snyder, DPM, MSc

Disclosures

Wounds. 2012;24(10):299-307. 

In This Article

Abstract and Introduction

Abstract

Amniotic membrane has been employed in the treatment of wounds for almost 100 years, beginning with early application of natural amniotic membrane obtained from labor and delivery to various types of burns and wounds. Amniotic membrane is rich in collagen and various growth factors that support the healing process to both improve wound closure and reduce scar formation. Unique properties of the material include the lack of immunologic markers, conferring an "immune privileged" status on the allografts; antibacterial properties; and the ability to reduce pain on application. The resurgence of interest in the use of amniotic membrane in a number of applications, including wound treatment, has occurred following improved techniques for preserving the natural membrane. Recently, techniques have been developed to dehydrate the material while preserving many of these wound-healing attributes, to produce a temperature-stable allograft. Future research will continue to yield more information on the unique properties of the amniotic membrane allografts.

Introduction

Historically, natural amniotic membranes have been successfully used for wound and reconstructive purposes since the early 20th century. John[1] reviewed the subsequent uses of human amniotic membrane over the 20th century to include a number of other applications during that period. These included reconstructive OB/GYN surgery, dentistry, and neurosurgical and general surgical applications.

Davis[2] reported a comprehensive review of some 550 cases of skin transplantation at the Johns Hopkins University in 1910. Sabella[3] and Stern[4] separately reported on the use of preserved amniotic membranes in skin grafting for burns and ulcers in 1913, although they were familiar with each other's work and collaborated. Amniotic membrane allografts as a wound allograft material have a number of beneficial properties inherent in their makeup. The material provides a natural scaffold for wound healing and contains various important growth factors and biological macromolecules important in wound healing. These molecules have been scientifically found to confer properties that reduce wound pain, suppress infection, suppress scar formation, and provide anti-inflammatory mediators.[1,7–10]

De Roth[5] first used amniotic membrane to repair eye wounds in 1940 after noting other materials used for skin grafting in the eye did not appear to have the inherent healing properties of amniotic membranes. Ophthalmologic use would go on to be one of the most popular applications of the material in the late 20th century.

Now numbering more than 45,000 applications by the ophthalmology community, amniotic membrane has been used for conjunctival reconstruction, burn treatment, pterygium repair, and a number of other similar applications, including use in children.[6]

In the latter half of the 20th century, natural amniotic membrane began to be used as a wound covering, beginning in the 1960s through the end of the century, with treatment for diabetic neurovascular ulcers, venous stasis ulcers, and various types of postsurgical and posttraumatic wound dehiscence.[1,7–11] In these applications, sections of the entire membrane, used in sheet form, were placed on the wound.

However, while the use of amniotic membrane was evidently valuable for the purposes contemplated by the surgeons, it was a somewhat difficult material to incorporate into routine use. While various methods were used to describe how the material might be prepared and preserved,[56–59] the tissue remained relatively difficult to reliably source, process, and handle, for obvious reasons. Transportation and storage similarly were difficult, and the material had limited widespread application.

In 2006, scientists developed methods for cleaning, preparing, and dehydrating human amniotic membranes for surgical use, creating dehydrated sheets of the material that could be cut into sections and stored. In this form, the material was easy to handle, stable at room temperature, and held a shelf-life of up to 5 years, as confirmed via a number of standardized tests. The ophthalmology community quickly adopted the use of this material in eye surgery, where there is now an extensive peer review of the literature, numbering dozens of articles on the subject.[1]

Over the past 5 years, application of this material has been extended to include wounds of other areas, including diabetic neurovascular ulcers, venous stasis ulcers, postoperative or posttraumatic chronic wounds, and postsurgical wound dehiscence. Now also numbering in the tens of thousands of applications, dehydrated amniotic membrane has been extended to other potential uses as a reparative membrane in orthopedics, neurosurgery, periodontology, OB/GYN, general and reconstructive surgery, and a number of other medical fields.[12–17]

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