Cornea Transplant (Penetrating Keratoplasty)
A corneal transplant surgery may restore vision in otherwise blind eyes. The most
common indication for this procedure is corneal decompensation following
cataract surgery.
Other common indications include: corneal ulceration, corneal scars, keratoconus,
herpes simplex and varicella zoster viral opacifications, Fuchs’ Endothelial Dystrophy,
and congenital abnormalities of the cornea.
The Corneal Transplantation Procedure
A complete preoperative evaluation is required prior to surgery. Every attempt to
confirm retinal and optic nerve function is made prior to the procedure, so as to
avoid unnecessary surgery.
The majority of adult patients have surgery under local anesthesia. General anesthesia
is often required for children, anxious, or uncooperative patients. After the anesthetic
is given, the
surgeon
may sew a ring to the ocular surface to support the eye. The
donor cornea is prepared using a punch or corneal trephine to create the corneal
“button.” The corneal button becomes the transplanted cornea. The diseased, or scarred,
cornea is then removed using a corneal trephine, creating a “recipient site” for
the transplanted tissue. Finally, the donor cornea is gently sewn into place with
ultra-fine sutures (approximately one-third the thickness of human hair).
Corneal transplantation may be combined with other procedures, particularly cataract
extraction with intraocular lens implantation.
Postoperatively, patients should expect a very gradual recovery of vision. In fact,
the best vision may not be obtained for six to 12 months or more following surgery.
Vision may, however, be improved immediately after surgery. The surgeon will occasionally
remove some sutures from the cornea within a few months after surgery. In general,
sutures are removed to help alleviate
astigmatism
once the cornea shows signs of being securely healed into place.
