Eye Banking and Corneal Donation

Introduction

Corneal disease is the major cause of blindness in India. The other causes include cataracts, glaucoma, diabetic retinopathy, macular degeneration, and loss of vision due to an accident. The donation of an eye will give eyesight to someone who has lost their vision. The cornea is the most commonly donated eye tissue. A corneal transplant is done widely to bring back the vision. Anyone who chooses to donate their eyes after death can do so through a variety of organizations, eye banks, and hospitals.

What Is Eye Banking?

In India, a three-tier community-eye banking system has been proposed. It consists of

1. Eye donation centers.

2. Eye banks.

3. Eye bank training centers.

Eye Donation Centers:

• Creating awareness about voluntary eye donation.

• Individuals interested in voluntary donations can register at eye donation centers.

• Eye donation centers coordinate with the donor families and motivate them to donate.

• The main work of eye donation centers is making arrangements for the collection of the eye after the death of the donor. Also, blood is collected for serology examination.

• Careful processing, packing, and transportation of the collected donor tissue to the attached eye bank.

Eye Banks:

• Eye banks are organizations that regulate the process of collecting corneas, storing them properly, finding qualified donors, and giving support for corneal transplants.

• It is the middle tier that comprises a strong network of 45 eye banks.

• Eye banks are closely linked to 2000 eye donation centers, and the suggested ratio is 1 to 50.

Eye Bank Training Center:

• This is the top tier of five eye banking training centers.

• They are responsible for tissue harvesting, processing, and distribution.

• Creating awareness.

• Training and skill upgrade of eye banking personnel.

What Are the Major Steps of Eye Donation?

• Donor selection.

• Tissue retrieval.

• Corneal examination.

• Tissue transportation.

• Storage of corneal tissue.

• Distribution.

How to Select a Donor?

Cornea used for transplants can be taken from any person, and there is no influence of age on the transplant outcome. Certain criteria where the cornea is not used if

• The person died from an unknown cause.

• The person had previous eye disease, eye surgery, and certain diseases that can pass from one person to another.

• People who had infectious diseases like hepatitis B, AIDS (acquired immunodeficiency syndrome), or septicemia.

• A person died due to blood cancer.

What Is Corneal Harvesting?

It is the surgical removal of the cornea from a deceased person. It can be either complete eye removal, called enucleation, or the cornea only, called in situ corneal excision. All these procedures are carried out by properly trained professionals like eye bank technicians, ophthalmology residents, ophthalmologists, and general practitioners.

It is a small procedure completed within half an hour and can be performed at hospitals, homes, and funeral grounds.

What Are the Procedures Before Corneal Harvest?

The cornea can be collected from the donor up to 12 hours after death. The ideal time is within six hours after death.

• Before corneal collection, informed consent is obtained from the close family or relatives of the donor.

• If the deceased person is a registered eye donor, the eye bank can proceed immediately with the corneal collection.

• Properly review the donor's medical and social history to match the eligibility criteria.

• If needed, relevant documents are taken from the hospital to know the cause of death.

• The eye bank has a list of criteria to match before proceeding to the collection of corneal tissue.

• Any information related to blood loss and blood transfusion is taken.

What Are the Procedures for Corneal Harvesting?

For corneal harvesting, a sterile field is maintained. The standard protocols include:

• Examination of the eye for any foreign objects or other defects using a pen torch.

• Preparing the face and eyes of the donor with povidone-iodine.

• Ascetic technique for cornea collection.

• Immediate preservation of the donor tissue in a suitable preservation medium.

• Also, blood or serum is drawn from the donor to screen for any infectious diseases.

• Blood tests for HIV (human immunodeficiency virus), syphilis, and hepatitis B are carried out.

How Is the Donor Tissue Stored?

• The eyes are stored in a moist chamber at two to eight degrees Celsius, which is a simple and inexpensive way for storing whole eyes. This is to be done within 48 hours after donor tissue is collected. These methods of storage are suitable for eye banks with limited resources.

• The collected donor tissue can be stored in a preservation medium like McCary Kaufman medium (MK medium) or Optisol, both maintained at four degrees Celsius.

• The cornea can be stored for up to 96 hours in MK medium and stored for 10 days in Optisol medium.

• The use of these preservation mediums helps for the long storage of viable cornea.

How Is an Examination of Donor Tissue Carried Out?

• When the cornea reaches the eye bank, proper examination of corneal tissue using a slit lamp is done.

• The endothelial cells are examined under a microscope. The number of endothelial cells present in the donor tissue is an important factor to consider because low endothelial cells may fail transplant surgery.

• Corneal surgeons evaluate the suitability of the cornea for transplantation.

• After proper examination, the viable cornea suitable for transplantation is sealed, packed, and transported to the hospital.

• The vial containing the cornea is labeled properly with the eye bank name and other details about the donor, the preservative medium, and the expiry date.

• After a successful corneal transplantation, the eye bank shares a letter of gratitude with the donor's family, and the donor's sacrifice is honored.

What Are the Challenges Faced in the Working of Eye Banking?

• Eye banking facilities in India are evolving, and major challenges include a lack of an organized eye banking system, unregulated working, and non-supportive legislature.

• Even with the help of eye banks, it is difficult to find enough people willing to donate their cornea. Family consent is also important before removing eyes or cornea.

• The lack of properly trained professionals and accredited systems makes the working of eye banking systems more difficult.

• Other areas of concern are a need for more public awareness and a lack of motivation among health professionals.

• The demand for quality donor corneas increases, and there is a gap between demand and supply.

• The awareness and willingness for eye donation vary in rural and urban populations. The close relatives and family members of the deceased person are not willing to give consent for eye donation.

• The majority of the people refused to discuss eye donation, raising legal problems and religious beliefs.

Conclusion

Proper working of the eye banking system in a country will help to reduce the social burden of blindness. Creating awareness about eye donation and registering themselves as voluntary donors is a major step towards overcoming the shortage of corneal tissue. People must realize that voluntary eye donation can be seen as one's social responsibility toward eliminating blindness.