Modern Eye Banking and Donor Selection
The EBAA and the US Food and Drug Administration track all donor tissue, monitoring for infection to minimize the chance of transmission. Screening of the donor medical record for potentially transmissible diseases is mandatory and is performed by an eye bank technician. Medical criteria that render a potential donor unsuitable for tissue recovery are listed in Table 15-3, and diseases that can be transmitted from donor corneas are listed in Table 15-4.
The eye bank technician also rigorously inspects the cadaver to rule out signs of high-risk behavior or other possible sources of potentially transmissible infectious diseases. Features like bluish-red cutaneous nodules (Kaposi sarcoma), needle marks, and recent tattoos can make the potential donor ineligible. If the cadaver passes inspection, blood samples are taken to rule out infectious diseases such as hepatitis B, hepatitis C, human immunodeficiency virus (HIV) infection, and syphilis.
Most eye banks accept corneal tissue from donors 2 to 75 years of age, but eye donation at any age is to be encouraged. Donor tissue from a person younger than 2 years is typically not used for transplant because it is extremely steep and flaccid, which makes the tissue difficult to handle and poses challenges in creating a watertight closure and achieving a predictable refractive outcome. The corneas of donors who have undergone cataract surgery are acceptable as long as they exceed the minimum acceptable cell count outlined in the eye bank’s policy (typically 2000 cells/mm2). Corneas with lower endothelial cell counts and clear stroma may be suitable for anterior lamellar procedures. Conversely, corneas with anterior stromal opacities but high cell counts may be used for EK. Patients who have undergone keratorefractive surgery are not suitable donors for PK, but if all other parameters are satisfactory, their corneas may be used for EK. Responsibility for determining whether a donor cornea is suitable for transplantation ultimately rests with the transplant surgeon.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.