4 Things to Tell Keratocones About Corneal Transplants

Question: I am a 41-year-old, long-time keratoconus patient and may require a corneal transplant. What can you tell me about the transplant and the risks?

Answer: First off, only about one in 10 keratocones need to seriously consider transplants. Patients might consider this option if they can’t wear spectacles and contact lenses but really want better vision, says Stephen E. Pascucci, M.D., of Scranton, Pa. A second, though less frequent, reason: Clouding or scarring of the corneal apex or scarring due to hydrops, in which the patient would experience glare and distorted vision.

“In the ’70s, if someone couldn’t be fit with a contact lens, then their only recourse was a penetrating keratoplasty,” says Wilmington, Del., ophthalmologist Rob Abel. With improved fitting techniques, however, you may do well enough with RGPs. Preliminary data from the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) study indicates that three out of four patients with moderate to severe keratoconus wear RGPs reasonably comfortably.

Some 5% of the patients (73 eyes of 63 patients) who entered the CLEK study with no corneal transplant have undergone penetrating keratoplasty in one or both eyes in 48 months (as of November 31, 1999).  “Certainly in the CLEK study they’re not flocking to transplant in droves, but it is a viable option for patients who need it,” says study chairman Karla Zadnik, O.D., Ph.D., of Ohio State University College of Optometry. “The primary indications for corneal transplantation in keratoconus remain poor vision and/or contact lens intolerance.”

Other factors patients should consider before having a transplant:

• Transplants on keratocones have a 95% or greater success rate. Other than the diseased cornea, these patients often don’t have additional eye health problems such as retinal disease that would limit their visual potential. Even though the graft may have an irregular surface, the post-op cornea is often easier to fit with contact lenses than the keratoconic one.
• The procedure is not risk-free. The biggest risk involved in the surgery is sight-threatening infection, which occurs in about 1 in 2,000 cases, Dr. Pascucci says. Other problems associated with the procedure: retinal detachment, bleeding and cataract, but these occur even less frequently. Another more common complication following penetrating keratoplasty is glaucoma, which may occur in 15-20% of phakic eyes. Severe bouts of rejection resulting in graft failure are rare, occurring in probably 1-2% of patients.

Additionally, Dr. Abel says there’s a 1% chance of obtaining poor tissue, a 5-7% chance of corneal graft rejection, and the inconvenience of an ocular wound and sutures. Some 10-20% of keratocones who undergo penetrating keratoplasty experience a homograft reaction.
Dr. Zadnik cautions that it’s too soon for CLEK researchers to draw conclusions about risk factors since few patients in the study have already undergone transplants. Her advice to patients: Discuss the benefits and risks with the surgeon, and even seek a second opinion.
• Patients must have realistic expectations. Patients will need to be on immunosuppressant drops for at least a year, maybe longer. Also, they may still need to wear contact lenses post-op.

Vision recovers gradually, and may take anywhere from 3-12 months. This will depend on the patient’s healing response, the surgeon’s choice of sutures and how long the patient uses an anti-inflammatory agent, Dr. Abel says.

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Dr. Joseph P. Shovlin 
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