THE UNIQUENESS OF EYE BANKING: EYE BANKS ENSURE THE SAFE SUPPLY OF CORNEAL TISSUE FOR TRANSPLANTATION, RESEARCH AND EDUCATION
Eye banking represents the dawning of the transplant revolution. The first successful corneal transplant took place in 1906 and the first U.S. eye bank opened in 1944. Eye banks have an illustrious history and have been the stewards of the gift of sight throughout the world for over six decades. Eye banks are unique because they recover, evaluate, and distribute tissue for transplantation, research and education. They alone handle the precious gift of sight from donor to recipient, allowing a comprehensive (from beginning to end) oversight of the process. In 2005 alone, 31,947 corneas were
transplanted in the United States. Additionally, 13,542 corneas were provided for research and 4,541 corneas were distributed for training purposes.
The Eye Bank Association of America (EBAA) is the national association that represents 80 U.S. eye banks and 13 international banks. Since 1961, the EBAA has been dedicated to the restoration of sight through the promotion of eye banking by promulgating medical standards, accrediting eye banks, and certifying technicians. The EBAA also helps to promote collegial relationships among eye banks to assure an adequate supply of corneas for patients in the U.S. These relationships have introduced scheduled surgery for corneal transplants; to date, there has been no need for a registry to list the availability of corneas.
The EBAA was the first national transplant organization to establish medical standards (1980) and ethical codes of conduct. All EBAA member banks voluntarily submit for inspection; following nspection, an EBAA Accreditation Board meets to review the observations and to action to accredit or deny. Accreditation is awarded for up to three (3) years. The Association works closely with banks to provide resources for them to achieve the maximum 3-year status. In conjunction with the American Academy of Ophthalmology (AAO), the EBAA urges all patients, surgeons and health care facilities to work solely with organizations that are EBAA accredited.
As there are marked differences in the medical, technical and practical aspects of organ, eye and tissue donation, the three categories of anatomical gifts have evolved as distinct specialty areas. Organ, eye and tissue donation differ significantly in their medical standards, federal regulatory requirements, timeliness of donor access, numbers of potential donors, costs structures and philanthropic community support. Anatomically, the cornea is uniquely protected from infection, significantly reducing the potential for transmission of systemic infectious disease. Corneas are avascular and are
bathed in clear aqueous humor and tears. Infectious agents that travel in the vascular tree must exit the blood stream and invade and permeate the clear aqueous humor and tears to reach the cornea. Viral adherence to the cornea may be inhibited by the proteins in these clear fluids. If there is gross bacterial contamination, it is often readily evident on slitlamp microscope inspection of the clear cornea. This differs from bone, skin, and other tissues, which by their physical nature cannot be as readily inspected.
Medical literature often refers to the cornea as “privileged’ because of the absence of blood vessels that in other anatomical sites transport antigens and pathogens from donor to recipient. The low rejection rate and relative absence of systemic disease transmitted through transplanted corneas is known to be attributable to the “privileged” nature of corneas. When corneal avascularity is combined with strict donor screening criteria, the opportunity for systemic infectious disease transmission has proven to be virtually nonexistent.
Timeliness is another critical issue that distinguishes eye recovery from organs and tissues. Delicate corneal cells remain viable for only a short period following death. Unlike many tissues that can be stored for years, the cornea can only be preserved for a matter of days. Eye banks must attempt to gather all necessary medical data from multiple sources, interview the next of kin, and receive blood test results in as short a time as possible following the death of a donor.
The information below outlines the thorough process that eye banks undertake to recover corneal tissue and ensure that it is safe for transplantation. At each step, attention to detail and quality is paramount.
EYE BANKING: THE PROCESS FROM DONOR TO RECIPIENT
THE CALL: An eye bank receives a call from a hospital or an organ procurement organization or another “federally designated” third party that an individual has died and has met preliminary criteria for donation. The eye bank has a very short time within which to contact the next of kin, obtain consent and recover the tissue. This generally needs to happen within 12 hours of the time of
death.
THE CONTACT: The eye bank contacts the next of kin, as defined by state law and the Uniform Anatomical Gift Act (UAGA), to obtain consent for the donation of the individual’s corneas.
THE CONSENT: If consent is given, the next of kin is asked to complete a medical-social history. The medical-social history provides the eye bank with information to make a donor eligibility determination.
THE DONOR MEDICAL REVIEW: After consent is given, the eye bank obtains copies of relevant medical records for review from the hospital, a step in the process of creating a complete donor profile. Eye banks pay close attention to the cause of death, any medications that were administered to the individual and if there was any blood loss.
THE PHYSICAL INSPECTION: If there are not any medical “rule outs,” an eye bank technician performs a physical inspection of the donor. This physical inspection contributes to the donor profile, and screens for physical signs of infectious disease or behavior that may have put them at risk, such as intravenous drug use. The technician also draws a sample of blood from the donor to be
tested for HIV I and II, Hepatitis B and C, and Syphilis.
THE RECOVERY: The donor’s eyes are then prepared for the procedure to recover the cornea. The technician dons a sterile gown and gloves, and drapes the donor eye to establish a sterile field. While the technician makes certain that the sterile field is not contaminated, the cornea itself is not considered sterile.
THE STORAGE: After removing the cornea, the tissue is placed in a storage medium. This medium keeps the tissue viable and helps to reduce bacterial growth. The technician then transports the cornea to the eye bank’s laboratory for refrigeration.
THE EVALUATION: Specially trained technicians evaluate the cornea through microscopes to ensure that it meets the eye bank’s strict criteria for transplantation.
THE ELIGIBILITY DETERMINATION: The eye bank’s medical director or his/her designee reviews the records for the donor and makes a final eligibility determination.
THE RELEASE OF TISSUE: If the medical director or his/her designee authorizes release of the tissue, the cornea is then sealed and packed in a container in wet ice (to ensure it remains between 2-8 degrees and does not freeze).
THE TRANSPORT: The cornea is labeled with a unique identification number to allow the eye bank to track the tissue from donor to recipient. It is then shipped to a surgeon or another eye bank for transplant.
Eye banks take their stewardship of the gift of sight very seriously. They train their staff to ensure that tissue recovered is safe for transplantation and is of the highest quality.
The EBAA holds eye banks to a high level of professionalism through the promulgation of medical standards, a stringent accreditation program, examination and certification for technicians, research grants, and continuing education seminars and scientific sessions.
Lions Eye Banks provide educational programs for health care professionals about the importance of offering the opportunity for donation and provide educational programs for Lions Clubs and the general public about the importance of and need for eye donation.