Cornea Transplant Database

The Foundation maintains the largest cornea transplant database in the Western Hemisphere. This database contains up to 15 years of information on over 5000 grafts. The data has been analyzed to document long-term graft survival rates and identify risk factors for graft failure.

  The patients in this study all received their transplants at Price Vision Group in Indianapolis, IN.
These patients had an outstanding 80% graft survival rate 10-years after their transplant. This is among the highest long-term survival rate reported in any of the studies conducted around the world, and is only equaled by the 10-year survival rate reported by the Mayo Clinic in Rochester, Minnesota.

   The graft survival rate was twice as high for first-time grafts as it was for regrafts. This shows how important it is to identify risk factors in order to anticipate and prevent failure of first time grafts.

   We found that the risk of graft failure is highest in the first year after transplant, and drops to a low but steady rate over longer time periods. We now know that for the first six months after receiving a transplant, the major risk is ocular surface disease, such as infection or ulcer. There is also a continuing risk over the long term that patients might reject their graft. Fortunately, medications are available to treat either ocular surface disease or rejection. Therefore patients should receive frequent follow-up, and they need to come in immediately for a checkup if they notice any problems developing with their graft.

   We found that another major cause of graft failure is endothelial cell failure. The endothelial cells line the inner surface of the cornea and continuously pump fluid to keep the cornea clear. There are a finite number of these cells and they do not get replaced. If the endothelial cells become diseased or damaged or if there are too few of the cells to keep up with the job, the cornea becomes cloudy. Our analysis identified several risk factors for endothelial failure, including small graft size, as well as pre-existing conditions such as diabetes.

   One of our most significant findings was that glaucoma increased the risk of all three major types of graft failure, including endothelial failure, rejection, and ocular surface disease. Glaucoma is a leading cause of blindness in the United States. Glaucoma affects nearly 1 out of 20 Americans and it targets any age group, even newborns. Scientific literature had previously recognized that elevated intraocular eye pressures associated with glaucoma could cause endothelial cell damage. However, it was surprising to find that glaucoma also increased the risk of rejection and ocular surface disease. This is likely due to the preservatives in the glaucoma eye drops. This finding is important because it may help doctors to more effectively manage their glaucoma patients and the glaucoma medications they prescribe.

  The Foundation's corneal transplant database helps us learn more and more each day about how to more effectively treat and manage patients who have lost their vision. As listed below, our findings have been published in leading ophthalmology journals so that doctors and patients worldwide can benefit from our research.

References:

1. Price MO, Thompson RW, Price FW. Risk factors for various causes of failure in initial corneal grafts. Archives of Ophthalmology 2003 121(8).

2. Thompson RW, Price MO, Bowers PJ, Price FW. Long-term graft survival following penetrating keratoplasty. Ophthalmology, 2003 110(7).

3. Dobbins K, Price FW, Whitson WE. Trends in the Indications for Penetrating Keratoplasty in the Midwestern United States. Cornea 2000 19(6): 813-816.

4. Price FW, Whitson WE, Johns SK, Gonzales JS. Risk factors for corneal graft failure. J Refract Surg 1996;12:133-146.

5. Price FW, Whitson WE, Collins KS. Five-year corneal graft survival. A large single-center patient cohort. Arch Ophthalmol 1993;111:799-805.

6. Price FW, Whitson WE. Graft survival in four common groups of patients undergoing penetrating keratoplasty. Ophthalmology 1991;98:322-328.

7. Price FW, Whitson WE. Progression of visual acuity after penetrating keratoplasty. Ophthalmology 1991;98:1177-1185.