The cornea is the clear, domed section covering the front part of the eye and is essential for our vision. This is because the cornea changes shape to help us focus, and refracts light as it enters the eye, enabling us to see what is in front of us. Most people have healthy corneas, but some people will experience injury, infection, or other conditions like keratoconus, which affect the cornea and prevent it from working as it should.
Corneal transplants are recommended for patients who have problems with their eyesight caused by issues with their cornea. A corneal transplant is a surgical procedure, the purpose of which is to remove all or part of a damaged cornea and to replace it with healthy donor tissue. There are two types of corneal transplants – full and partial thickness. The type that you are offered will depend on the parts of the cornea that you need to have replaced.
A full-thickness corneal transplant is also known as penetrating keratoplasty or PK procedure. These are also the most common type of corneal transplants.
During a full-thickness corneal transplant, your eye doctor at Santa Barbara Eyecare will surgically remove a circular piece of the damaged cornea from the center of your cornea. This is usually done using a small, circular cutting instrument called a trephine. Once it has been removed, it is replaced with some donated corneal tissue which is held in place using tiny stitches.
Full-thickness corneal transplants can be done using a local anesthetic, or in some cases, a general anesthetic may be required. The entire process should take less than an hour, but you’ll usually have to stay in overnight for one night following your procedure.
A partial-thickness corneal transplant is a more recent technique that has been developed and allows for only parts of the cornea to be transplanted – usually either the front or the back. This enables more targeted treatment for patients that require it.
Some of the techniques that could be used in a partial-thickness transplant could include:
Anterior lamellar keratoplasty (ALK) removes and replaces the outer front layers of the cornea.
Deep anterior lamellar keratoplasty (DALK) is used to remove and replace the outer and middle layers of the cornea only.
Descemet’s stripping endothelial keratoplasty (DSEK) replaces the inner lining of the cornea with around 20% of the corneal stroma (supporting tissue).
Descemet’s membrane endothelial keratoplasty (DMEK) replaces only the inner layer of cells of the cornea.
The benefits of partial-thickness corneal transplants are that patients can usually recover from them more quickly, with their sight being restored much more rapidly. There is also a lower risk of complications. Like full-thickness corneal transplants, the procedures can be performed using either local or general anesthetic, and usually take under an hour.
All corneal tissue is carefully screened for disease and infection before it is transplanted into the recipient, meaning that it is extremely safe to be used. The risk of complications from donated corneal tissue is exceptionally low.
After you are discharged home following your corneal transplant, your eye doctor at Santa Barbara Eyecare will give you a specific set of instructions to follow which relate to how to best care for your eyes. It is essential to follow these since they will help to minimize your risk of complications, improve your rate of healing and ensure the best possible outcome from your procedure.
These instructions will include information about:
Taking time off of work
Bathing and showering and the importance of protecting your eyes
Sensitivity to light
Wearing your dressing
Taking prescribed eyedrops or medications
Attending your follow-up appointments
The time it takes for your vision to return to normal can also vary, from anywhere from a few weeks to a year. You’ll probably also need to use glasses or contact lenses to ensure your vision is as clear as possible.
For more information about corneal transplants, call Santa Barbara Eyecare in Santa Barbara or Goleta, California at (805) 967-9990 with any questions or to schedule an appointment today.