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Combine the final generosity of a passing life with the skill of a cornea surgeon and the dedication of tissue banks and you have a commanding success in modern medicine.
For nearly 50 years, the nation’s eye banks have worked quietly and tirelessly to supply vision-saving corneal tissue to cornea surgeons and their grateful patients. It hasn’t been easy: Growing demand, enhanced government regulation, reimbursement concerns and emerging competition from for-profit eye banks are making the provision of donor tissue more complicated for both the medical-provider and tissue-banking communities.
But despite these challenges, eye banking remains a huge success story—one made possible by the sight-giving gifts of thousands of donors, and by Eye M.D.s working with the nation’s tissue banking network.
A vision for collaboration. The partnership enjoyed by eye surgeons and eye banks in the United States was forged largely by the Eye Bank Association of America (EBAA) in Washington, D.C. “The EBAA has always been a unique group in that it has both MDs and eye bankers actively involved,” said Woodford S. Van Meter, MD, medical director for Lions Eye Bank of Lexington–Vision Share and professor of ophthalmology at the University of Kentucky. “This means you have the endpoint users—the cornea surgeons—at the same meeting discussing the process with the procurers—the eye bankers who will retrieve the cornea, then evaluate and distribute it. Eye bankers and cornea surgeons work together on both the medical advisory board and the accreditation board. The EBAA now also has a seat at the Academy Council.”
Further evidence of the collegiality of the two groups includes collaboration on educational symposia as well as the recent decision of the journal Cornea to publish abstracts from the EBAA’s Scientific Sessions.
Quality corneas—hot off the globe. Cornea surgeon Marian S. Macsai, MD, the incoming chair of the EBAA, said, “The EBAA member banks have done a great job in meeting the needs of patients and surgeons. Through our accreditation process, we have made corneal transplantation one of the safest forms of transplantation today. In fact, surgeons and patients are usually able to schedule their surgery, order tissue cut to the surgeon’s specific needs and have it arrive at the appointed time. This high level of service has created the mistaken perception among some people that corneal tissue is as easy to order as an IOL. Some younger surgeons, in fact, may not be aware of all that is involved in the procurement, processing and distribution of this precious tissue.” Dr. Macsai is chief of ophthalmology at NorthShore University Health System in northern Illinois and professor of ophthalmology at the University of Chicago. “One of my challenges as chair of the EBAA is to increase surgeon involvement in the association.”
FOUR TURNING POINTS FOR EYE BANKING
The effectiveness of the current system was several decades in the making, according to Donald E. Ward, vice president of the National Eye Bank Center in Memphis, Tenn. Mr. Ward has been involved in eye banking for more than 35 years. During that time, the profession underwent numerous changes, he said, at least four of which made eye banking a significantly better enterprise.
- Supply met demand. The supply of human corneas was once an issue but not anymore. “Before 1975, eye banks stored corneal tissue in the form of whole eyes by refrigeration in a moist chamber,” Mr. Ward said. “In 1975, the development of corneal storage media revolutionized cornea transplantation. Instead of having to make a cornea available within 24 hours, you could keep the cornea in a tissue culture medium-type storage for approximately two weeks. The utilization of corneal tissue became much more effective, and the number of eye banks in the United States increased rapidly.”
Gerald J. Cole, president and CEO of Tissue Banks International (TBI), which is based in Baltimore and is an EBAA member organization, agreed and noted that in the early years of eye banking, “There was a lot more need than there were corneas available. But we made some improvements in corneal preservation. By the late 1980s and early ’90s, patient waiting lists were a thing of the past. This was a great accomplishment, one that is unique in all of transplantation. We now have a cornea for everyone in the United States who needs one.”
- Anatomy got specific. The second major change was the advent of lamellar transplants. “Demand for corneal tissue rapidly increased as surgeons came to strongly prefer deep lamellar transplants,” Mr. Ward said. “Eye banks had to take up this challenge and learn how to prepare the tissue. This development has really revolutionized the way eye banks operate.”
Mr. Cole agreed. “When endothelial grafting came along, first with DLEK and then DSEK, eye banking broadened its scope in order to prepare the tissue in the way that surgeons wanted and needed for their patients. Within about two or three years, eye banks adjusted well to providing pre-cut tissue.”
- The cut could be imaged. High-tech imaging also contributed to successful harvesting of corneas. Optical coherence tomography has been especially helpful. “When we do pre-cut corneas, we need to assess our work,” Mr. Ward said. “OCT allows us to verify that we have achieved the consistency of the cut we had anticipated.” It also clearly shows whether a donor had undergone refractive surgery, a rule-out for full-thickness cornea transplantation because the weakened tissue can disintegrate in a surgeon’s hands. Dr. Van Meter noted that when LASIK is performed by a particularly skillful surgeon, the scar can be nearly impossible to detect without OCT. With more than 1 million LASIK procedures performed each year in the United States, OCT can play an important role in screening those corneas out of the transplant pool, he said. “A LASIK donor cornea, if not detected, can split into two lamellae and make suturing very difficult for a penetrating graft, compromising the integrity of the patient’s eye on the operating table.”
- The cut got cleaner. An even more recent advance in eye banking is TBI’s VisionGraft Sterile Cornea, an irradiated cornea designed for use in tectonic transplant procedures. According to TBI officials, the new product offers a dramatic reduction in the risk of disease transmission, is shelf-stable for at least one year and is ready to use at room temperature, making it obviously useful for trauma procedures when even a one-day wait for donor tissue is unacceptable. “The VisionGraft Sterile Cornea encapsulates important features and benefits from the donor side and the recipient side,” said David Pennington, TBI’s vice president for ocular operations. “From the donor side, corneas oftentimes cannot be used for various reasons, including low endothelial cell count. Some of these corneas can be used for research, but others must be discarded. The VisionGraft program, however, takes a lot of that tissue and converts it in a way that increases the pool of available donor tissue.”
These corneas are sent through a rigorous irradiation process and can be specially cut for certain procedures, Mr. Pennington added. They are used as glaucoma patch grafts in which a tube shunt or some sort of valve may have been placed and the irradiated tissue is used to cover those devices. These are clear tissues that have certain advantages over other tissues, like sclera, and they also can be used for emergency patch grafts for penetrating traumas. Mr. Pennington noted that TBI is exploring the possibility of using the VisionGraft Sterile Cornea for both deep anterior and superficial anterior lamellar keratoplasties. “We haven’t released it for these indications, but we are in the research phase and have gotten some pretty good results so far.”
In addition to corneas, TBI stores limbal cells and scleral tissue—and even pericardium and fascia lata for use by glaucoma surgeons. And although TBI started out as an eye bank, it now manages tissues for many other transplantation contingencies, including skin, saphenous veins, heart valves, Achilles tendon and bone, such as humerus, iliac crest, femur, tibia and fibula.
DEFINING THE BURDENS ON BANKS
Donald Tan, MD, medical director and head of the cornea service at Singapore National Eye Center, foresees more demands being placed on eye banks as corneal transplant procedures expand and evolve. He outlined the impact of the following four procedures on eye banking resources.
Anterior lamellar keratoplasty—OK for donor quality to vary. Dr. Tan noted that at Singapore National Eye Center, 30 percent of the transplants performed last year were ALK procedures. “ALK does not strictly require healthy endothelial tissue, meaning that far more corneas can be utilized. However, since very few surgeons currently have converted to ALK surgery, at present this difference is not significant.”
Dr. Tan noted that the current cornea utilization rate at the Singapore Eye Bank is 93 percent. “ALK deserves a revolution, but at present it has not fully taken off, mainly because it’s a difficult and challenging surgery and prior studies have suggested poorer visual outcomes,” Dr. Tan said. He added, however, that studies are emerging to show that ALK surgery for keratoconus, corneal scars and stromal dystrophies can now match and even surpass the visual results obtained with PK. “ALK will always remain highly attractive because endothelial rejection is totally obviated.”
Endothelial keratoplasty—precipitous learning curve. “EK has the opposite effect,” Dr. Tan said. “Because more and more surgeons are learning EK surgery, there will be more need for corneas until the primary graft failure rates drop. These failures are mainly due to the surgeon learning curve. Moreover, the idea of one cornea being used for two patients—that is, that the anterior cap can be used for an ALK case—is logistically impractical and rarely possible.”
Dr. Tan added that early cases of Fuchs dystrophy are now being treated with EK because of its visual success, further increasing the demand on eye banks. Other pressures include surgeons’ requests for higher-quality endothelial tissue for EK procedures compared with PK procedures and the occasional problem of tissue wastage in the processing of pre-cut corneas.
Descemet membrane endothelial keratoplasty poses troubles. Dr. Tan said that the advent of more challenging procedures like DMEK might further increase the demand for corneal tissue. DMEK’s learning curve, he said, results in much higher rates of donor loss, inverted donor tissue and postoperative endothelial cell loss.
Descemet stripping endothelial keratoplasty may become easier. In the short term, Dr. Tan expects the new donor inserters for DSEK to have a major impact on better graft survival and endothelial cell-loss rates. Currently, many surgeons are seeking an alternative to the conventional “taco” folding technique, which generally has a cell loss rate of about 30 to 40 percent at six to 12 months. Ideally, he said, cell loss rates may possibly be halved with some of these inserters, and this should also make the DSEK procedure much easier and more predictable. “Our clinical trials with the Tan EndoGlide device (Angiotech Pharmaceuticals) suggest that endothelial cell loss rates at six and 12 months are in the region of 15 percent,” Dr. Tan said. “Other promising insertion devices include the Neusidl Corneal Inserter (NCI, Fischer Surgical) and the EndoSaver Corneal Endothelium Delivery Instrument (Ocular Systems).”
THE ECONOMIC ARRANGEMENTS
Since EBAA’s inception, all of its member banks have been required to be not-for-profit 501(c)(3) charitable organizations. In the last several years, however, some for-profit eye banks have emerged, stirring competition among eye banks for the first time.
Patricia Aiken-O’Neill, Esq., president and CEO of the EBAA, said, “We don’t receive direct reports on the quality systems within nonmember eye banks, but by all available reports, cornea tissue provided for transplantation is safe, whether it is being provided by EBAA member eye banks or not.” The EBAA, which represents 100 percent of the not-for-profit eye banks in the United States, is discussing the possibility of allowing commercial eye banks to join the organization. Any proposal to bring for-profit organizations into the fold would need to be voted upon by the membership.
Questions for the private sector . . . Though reserving judgment about the advent of commercial eye banks, Dr. Van Meter does have concerns about introducing the profit motive into eye banking if those facilities operate outside the umbrella of EBAA medical standards. “I am concerned about the proliferation of for-profit banks,” he said. It’s important, he continued, “that surgeons know that they should be using tissue from an EBAA-certified eye bank because the EBAA accreditation process reviews and validates its procurement procedures.”
. . . and the public sector, too. Another recent development is the emergence of competition even among the nonprofit EBAA-affiliated eye banks. “The eye banking community has always been a very collegial community,” said Ms. Aiken-O’Neill. “But the economic pressures that are affecting the medical profession are also affecting the eye banking profession. Our member banks range from the very small, almost mom-and-pop eye banks, to the very large. There has already been, and will continue to be, some consolidation. Because all member eye banks have to adhere to the same quality standards, that consolidation should not affect the quality of the donor tissue. But it may well affect the ability to meet the needs of the cornea surgeon.”
Consolidation: one example. In 2005, TBI established the National Eye Bank Center, a centralized cornea processing center in Memphis, Tenn. The facility is the distribution site for approximately 25 TBI tissue-recovery sites around the country. “The rationale for the center was that some of the equipment involved in eye banking today is quite expensive—the femtosecond laser at several hundred thousand dollars, OCT at about $60,000 and microkeratome systems at about $50,000 each,” Mr. Ward said. “Plus, the expectations placed on eye banks have increased—primarily in terms of FDA regulations—and very specialized training is required to do the pre-cutting. Having a center of excellence streamlines the process and spares the recovery centers from many of the regulatory issues, the extensive training required and the cost of providing tissues in the new and more specialized configurations.”
ENGAGING A NEW GENERATION OF SURGEONS
One of the biggest challenges for eye banking and corneal transplantation is maintaining the interest of cornea surgeons, said Dr. Van Meter. Namely, he has noticed a “graying” of the surgeons who have had a longtime involvement in the EBAA. “In the 1990s there was a substantial influx of young cornea surgeons, but that influx stopped about 10 years ago,” he said. “Although some younger surgeons participate now, the number of young cornea surgeons involved in EBAA committees is probably down 50 percent in the first decade of this millennium compared with the 1990s. Involvement with local eye banks and participation in EBAA committee service is a good way to fast-track one’s corneal career and get involved in research activities.”
Calling all volunteers. Consequently, involving more young volunteer surgeons in eye banking is a major goal of the EBAA. “Part of the strength of eye banking has been the historical and ongoing partnership between cornea surgeons and the eye banking community. One of the cornerstones of our organization is the medical advisory board, which promulgates standards for the recovery and distribution of corneal tissue, and this is composed of volunteers,” Ms. Aiken-O’Neill said. “The majority of people who sit on this board are eminent cornea surgeons who volunteer their time. The same is true with accreditation. We have a very active accreditation program through which we send two inspectors out to inspect eye banks, and one of the two inspectors is a cornea surgeon.”
As EBAA chair, Dr. Macsai said her vision for the association encompasses these challenges. “The relationship between cornea surgeons and eye banks is symbiotic,” she said. “Neither can serve patients and restore vision without the other. Together, eye banks and surgeons create a strong force to represent the needs of our patients.”
A Rocky Road for Donor Corneas
Although cornea donations have risen slightly each of the last several years, Dr. Van Meter explained how quickly a potentially large number of donors can be whittled down to a relatively modest number. In Kentucky, for example, where about 35,000 people die annually, he estimated that:
- Around 40 percent die at home, in hospice care or at the scene of an accident. Those individuals are not automatically referred for tissue donation, so, realistically, only the 21,000 deaths that occur in hospitals generate a call to a tissue bank.
- Of those, 85 percent are too young or too old or have infections, leaving about 3,150 donors.
- Of those, 80 percent of families do not give permission for organ donation, leaving about 600 donors.
- Of those, medical record review or further exam of the body make about 15 percent unsuitable for cornea retrieval, leaving about 500 donors.
- Of those corneas harvested and evaluated microscopically, 20 percent are rejected for cell counts or defects, leaving 400 donors, or 800 corneas, available.
“The eye bank will rule out a cornea if there is something in the history that increases the risk for infectious disease, such as hepatitis, imprisonment or IV drug abuse, or if there is any problem noted on slit-lamp exam or specular microscopy,” Dr. Van Meter said. “Other disqualifications with which people may be less familiar include living in the United Kingdom or on a military base in Europe between 1980 and 1996, or living in Europe for a total of five years or more cumulatively between 1980 and the present.” Dr. Van Meter explained that these disqualifications address the risk of prion disease, also known as ‘mad cow’ disease. Potential donors who have had tattoos in the past year that were not professionally administered are also eliminated because of the risk of HIV transmission. Even if they test negative for HIV, they may seroconvert up to a year later, he said. “Eye banks want to provide corneas of the best quality, and the FDA and the EBAA have developed strict medical standards to ascertain that no infectious diseases are transmitted, and that if any ever are transmitted, they can be tracked.”
The current fees charged for a donor cornea vary depending on a number of criteria, Ms. Aiken-O’Neill said.
Each individual bank sets its fee, which may range up to $3,500 or more. The fee includes the cost of procurement and processing, serologic testing (HIV 1 and 2, hepatitis B and C, and usually syphilis and HTLV), eye-bank staff availability around the clock and overnight shipment of tissue to the cornea surgeon.
To learn how to consent to be a tissue donor, physicians or patients can start the simple process by visiting www.tbionline.org/become-a-donor.php and clicking on “Donate Life America.”
Meet The Experts
PATRICIA AIKEN-O’NEILL, ESQ. President and chief executive officer of the Eye Bank Association of America in Washington, D.C. Financial disclosure: No interests beyond employment by the EBAA.
GERALD J. COLE President and chief executive officer of Tissue Banks International in Baltimore. Financial disclosure: No interests beyond employment by TBI.
MARIAN S. MACSAI, MD Chief of ophthalmology at NorthShore University Health System in northern Illinois and professor of ophthalmology at the University of Chicago; incoming chair of the Eye Bank Association of America. Financial disclosure: None
DAVID PENNINGTON Vice president for ocular operations at Tissue Banks International in Baltimore. Financial disclosure: No interests beyond employment by TBI.
DONALD TAN, MD Medical director and head of the cornea service at the National Eye Center of Singapore. Financial disclosure: None.
WOODFORD S. VAN METER, MD Medical director for Lions Eye Bank of Lexington, Ky., and professor of ophthalmology at the University of Kentucky in Lexington. Financial disclosure: None.
DONALD E. WARD Vice president of the National Eye Bank Center in Memphis. Financial disclosure: No interests beyond employment by TBI.