CORNEAL SURGERY OVERVIEW
The cornea is the specialized dome-shaped front surface of the eye. Most of the refractive and focusing power of the eye is in the cornea. A corneal transplant is sometimes necessary when the corneal tissue becomes damaged due to injury, infection, or disease.
Corneal Transplants
During a corneal transplant, the damaged tissue is replaced with healthy tissue donated from a local eye bank. Traditionally, a penetrating keratoplasty (PKP) would be the type of corneal transplant required to treat many corneal problems. Increasingly, the cornea has been the focus of advanced laser and surgical procedures to correct vision for those with medical ocular problems as well as those requesting a reduction in the need for glasses. The Descemet’s Stripping Endothelial Keratoplasty (DSEK) and Deep Anterior Lamellar Keratoplasty (DALK) procedures are examples of these new advances in surgical procedures.
Gary Barth, MD, is the corneal and external disease specialist at ECI. Corneal transplants are the most common type of transplants done in the world with a success rate well over 90%. In America, there is generally no shortage of corneas due to the excellent eye banks around the country. For seven years, Dr. Barth was the Medical Director of the Eye Bank of Sonoma. Eye banks are now supplying increasingly sophisticated pre-cut tissue for treating problems with either the front of the cornea or the posterior part of the cornea.
Conditions Most Likely to Require Corneal Transplants
Since the cornea is the foremost part of the eye, the cornea is often a target for injury. The following conditions are a partial list of traumatic corneal problems that might require eventual corneal transplant surgeries:
- Foreign bodies in the visual axis
- Chemical injuries
- Penetrating injuries, such as industrial accidents
- Corneal lacerations from blunt trauma
- Corneal drying from injuries that prevent the eyelids from closing
Traditional and new types of corneal transplants are often needed for the following medical conditions:
- Corneal endothelial dystrophy
- Bacterial and viral corneal infections
- Persistent corneal swelling after cataract surgery
The cornea has remarkable healing properties and copes very well with minor injuries or abrasions. Deeper scratches or injuries can result in scarring; and when this occurs in the visual axis, the vision may be affected, even to the point of blindness. Corneas with partial thickness scars can be treated with traditional penetrating corneal transplants or, in some cases, with deep lamellar or partial corneal transplant. The deep anterior lamellar transplants (DALK) have a quicker recovery. Patients with either scarring from keratoconus or have become unable to wear contacts to correct their keratoconus are often suitable for this meticulous and technically challenging type of corneal transplant.