WHAT IS AN EYE BANK?
An eye bank is a non-profit organization that is involved in the donation, procurement, testing, processing, preservation, storage and distribution of human ocular tissues and cells for use in corneal transplantation, ocular surgery, research and education.
The Eye Bank is responsible for all aspects of the process of providing safe, quality tissue to ensure maximum success for the recipients. The Eye Bank operates a comprehensive Quality Assurance system conforming to the highest international standards for safe tissue, and the highest ethical standards for ensuring respect and consideration of the donor's gift.
The donated eyes and the donor's medical and social history are evaluated by the eye bank in accordance with national, European and international laws and regulations. Moreover, the Medical and Technical Standards of the European Eye Bank Association (EEBA), set out in the documents “Minimum Medical Standards” and “Technical Guidelines for ocular tissues” which are reviewed every year, have evolved in order to neatly complement the EU Directives on “setting standards of quality and safety for the donation, procurement, testing, processing, preservation, storage and distribution of human tissues and cells” contained in the three Directives: the parent Directive (2004/23/EC) which provides the framework legislation) and the two technical directives (2006/17/CE and 2006/86/EC). These Directives set out the minimum legal requirements for guaranteeing a European wide level for standards of quality and safety which have to be fulfilled by EU Member States.
With the recipient’s safety in mind, only corneas that have met strict evaluation guidelines set forth by national competent authorities, the EU and EEBA are distributed.
A BRIDGE BETWEEN DONATION AND TRANSPLANT
The activity of eye banking aims to provide ophthalmic surgeons with an efficient and reliable service of retrieval, collection, sorting and distribution of corneas suitable for the purpose of transplantation. The process is designed to ensure the safety, constant monitoring and the highest possible quality of the corneal tissues. Eye banks serve as a bridge or conduit from the donor and their family to the surgeon and their recipient(s)
THE PHASES OF THE PROCESS
- THE CALL: An eye bank receives a call from a hospital or Transplant Coordination/ Procurement Unit or another “officially 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 24 hours of the time of death
- THE CONTACT: The local Transplant Coordination/Procurement Unit, or eye bank personnel, contacts the next of kin, as defined by national law, 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. Sometimes there are different consenting practices for the removal of the whole eye (in some jurisdictions the ocular globe is regarded as an organ) as against the retrieval of only the cornea (considered as a tissue).
- 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 no medical “contraindications” the designated medical staff or 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 behaviour that may have put them at risk, such as intravenous drug use. The operator also draws a sample of blood from the donor to be tested for HIV I and II, Hepatitis B and C, and Syphilis.
- THE RETREIVAL: The donor’s eyes are then prepared for the procedure to retrieve 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. During the retrieval, the donor is always treated with dignity and respect.
- 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 evaluation and short-term or long-term storage depending on whether the individual eye bank practices hypothermic storage at 4°C (maximum storage time: 14 days) or organ culture storage at 31°C (maximum storage time of 5 weeks for selected surgery cases).
- THE EVALUATION: Specially trained technicians evaluate the cornea through microscopes to ensure that it meets the eye bank’s strict criteria before release 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 (for hypothermic preserved corneas) or in a special validated container designed to maintain the cornea at room temperature (for organ cultured corneas).
- THE TRANSPORT: The cornea is labelled 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 in response to a specific tissue request for a scheduled surgery date.
- THE FOLLOW-UP: Correspondence with, and support of, donor families and recipients is important. Support is available to families of eye donors before, during and after donation. Although the identity of recipients cannot be revealed, a donor family can request to know how many people have been helped through transplantation and how they are progressing. By the same token, corneal recipients are monitored in order to raise the alert if there is any unexpected complication, serious adverse reaction or event which may put their help at risk, or that of other recipients who may have received tissue from the same donor source.
Eye banks take their responsibility for the gift of donation very seriously. They train their staff to ensure that the eye tissue that they recover is safe for transplantation and is of the highest quality. The EEBA holds eye banks to a high level of professionalism through the promulgation of medical standards and continuing education seminars and scientific sessions.
WHAT TISSUES DOES THE EYE BANK PROVIDE?
Donated eyes provide corneas for sight restoration, where the cloudy or diseased cornea is replaced by a clear, healthy donor cornea. In particular, eye banks are sometimes able to specially selected and/or prepared tissues for specific transplant procedures such as:
- Cornea for Penetrating Keratoplasty (PKP)
- HLA-Typed Cornea for Penetrating Keratoplasty (typed PKP)
- Cornea for Tectonic Penetrating Keratoplasty (tect.graft)
- Cornea for Keratolimbal Allograft (KLAL)
- Cornea for Endothelial Keratoplasty (EK)
- Pre-cut Cornea (Lenticule) for Endothelial Keratoplasty (DSEK/DSAEK)
- Cornea prepared for Descemet Membrane Endothelial Keratoplasty (DMEK)
- Cornea for Anterior Lamellar Keratoplasty (ALK/DALK)
- Lenticule for Anterior Lamellar Keratoplasty (ALK/DALK)
Sclera (the tough 'white' part of the eye) is used for reconstructive surgery following trauma or tumour removal.
Amniotic membrane derived from the placenta can be used to provide a 'living bandage' for ocular surface disorders following infection, injury or disease process.
Additionally, if authorised by their competent regulatory authorities, eye banks are often able to provide tissues (unsuitable for therapeutic purposes) for research, training and educational purposes.