A corneal transplant may be needed when the cornea is permanently scarred, or the corneal shape is very abnormal (as in keratoconus) or when the endothelial pumping cells at the back of the cornea are not functioning well (as in Fuchs’ dystrophy).  

Learn more about keratoconus   

Learn more about Fuchs' dystrophy   

There are two principal types of corneal transplant: Partial thickness or lamellar transplants (e.g. DALK, DSAEK, DMEK) and full thickness transplants (e.g. PK). Your surgeon will advise you of the type of transplant best suited to your condition.

DMEK and DSAEK

Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK) are two types of lamellar corneal transplants where the diseased inner corneal layer (the endothelium) is replaced with that of a healthy donor endothelium. DMEK and DSAEK are new transplant surgical techniques which have substantially replaced full thickness transplants for management of Fuchs’ dystrophy and corneal decompensation.

The benefits of DSAEK or DMEK are a smaller operation for the eye compared to a penetrating graft, as surgery is carried out through a microscopic keyhole incision, and requires only a few stitches to close the wound. This leaves the eye much stronger than after a penetrating graft, and also eliminates the problems of regular and irregular astigmatism that accompany all penetrating grafts. Following DSAEK or DMEK surgery, most patients achieve driving standard vision within a few weeks of surgery.

DALK

Deep anterior lamellar keratoplasty (DALK) is another type of lamellar corneal transplant where the diseased outer corneal layers (the stroma) is replaced with that of a healthy donor cornea. It is a challenging corneal transplant procedure that is most often performed for keratoconus and dense corneal scars.

PK

Penetrating keratoplasty (PK) involves replacement of the diseased cornea with a full-thickness healthy corneal donor tissue. It is the most established and commonly performed corneal transplant operation world-wide. Whilst it still has a role to play in management of advanced keratoconus or conditions that affect all layers of the cornea, it has been largely replaced with lamellar techniques discussed above, and is no longer recommended for Fuchs’ endothelial dystrophy.

The main risks associated with DMEK or DSAEK are:

1. Dislocation of the transplant, necessitating a second operation to re-attach the graft, or repeat surgery
   
2. Corneal graft rejection
   
3. Infection
   
4. Primary donor transplant failure

Having one week off work will help your eye recover. Walking and light aerobic exercise will not harm the eye. Avoid accidental direct trauma to the eye. Contact sports and gardening can be associated with accidental direct trauma to the eye. Ensure that you wear appropriate eye protection for these activities, if they cannot be avoided.

Direct trauma to the eye poses a lifelong risk of incurring permanent damage to any eye that has had a penetrating graft (PK). The risk associated with direct trauma to the eye is much reduced after lamellar grafts (DALK, DMEK, DSAEK).

A pad will be placed on your eye after the surgery. This pad can be removed the following morning when the eye drops are commenced. Two different eye drops are used postoperatively: one is an antibiotic to prevent infection, the other is a steroid drop to reduce inflammation. You will be given a plastic shield to protect your eye at bedtime. Use this every night for one week.

You will be reviewed at 6-weekly to 3-monthly intervals for the first 12 months after corneal transplant surgery, unless conditions arise that require more frequent review. You will have blurred vision for some time postoperatively. The recovery period for good vision is very prolonged (at least 12 months, usually 18-24 months) for PK and DALK, although most patients will notice an improvement within a few days of surgery. Vision recovers more rapidly after DMEK and DSAEK, usually by 1-3 months.

There is a lifelong risk of corneal transplant rejection. This is reduced with diligent use of steroid drops as instructed postoperatively. The corneal transplant needs to be checked urgently in an emergency, or if the eye becomes red, sore, and irritated, or the vision worsens.

Patients receiving a corneal transplant may need cataract surgery, glaucoma surgery or a repeat corneal transplant many years later. In some cases, the corneal transplant may last more than 30 years.