Corneal Graft

Corneal graft, corneal transplant,


Corneal Grafts are available at the following centres:

BMI Mount Alvernia Hospital
Manchester Royal Eye Hospital


Corneal graft operations are performed to replace damaged, diseased or scarred corneas with health cornea tissue. The cornea is the curved window at the front of the eye that must be clear and regular to see. It is in front of the iris [the coloured part of the eye] and the pupil. The photo above (main) shows a corneal graft. The stitching is visible as the multiple black lines. A corneal graft is also known as a corneal transplant or a keratoplasty. Conditions that could potentially lead to a graft include Fuchs Endothelial Dystrophy, Herpes Simplex Viral Disease, but more commonly, Keratoconus.

When keratoconus becomes very advanced and fitted contact lenses no longer provide adequate vision, the only solution to improving vision may be with a corneal graft. Corneal grafts have been one of the major transplant success stories and have been used in ophthalmology ever since the first successful transplant in 1905.

LaserVision’s Dr Arun Brahma is a keratoconus specialist who has introduced several new techniques over the years to the region, including collagen cross linking, Kera-rings, INTACs and topographic guided laser. He has also pioneered numerous corneal transplant techniques in Manchester and is regularly referred patients from across the country and overseas. Keratoconus treatments are suggested based on individual circumstances taking into account the stage of progression, age and patient lifestyle amongst many other factors.

Corneal grafts for keratoconus can be performed either as a full thickness transplant (Penetrating Keratoplasty) or a partial thickness transplant (Deep Anterior Lamellar Keratoplasty). Both variations can be performed either by hand or with the use of the IntraLASE™ femtosecond laser.


Your LaserVision consultant surgeon can expertly guide you through the best treatments for you. Each treatment is personalised to achieve the best results.


 

Learn more about corneal graft surgery below:

 

Partial Thickness Surgery

Deep Anterior Lamellar Keratoplasty (DALK)

In modern corneal graft surgery we aim to preserve the layers of the patients cornea that still work well. In many corneal problems, for example keratoconus, the inner layer of the cornea, the “endothelium” does work normally. In a partial thickness corneal graft operation or “deep lamellar keratoplasty”, we leave this thin layer of endothelium behind, and stitch the donor corneal graft on top. We do this because a lamellar graft carries a much reduced rejection risk, and preserves your healthy endothelium – and both of these mean improved graft survival. In some cases it is not possible to preserve the inner layer, a small number of operations will need to be converted to a full-thickness graft, because of perforation of the inner layer.

Femtosecond Laser Assisted Deep Anterior Lamellar Keratoplasty (FsDALK)

Latest laser technology now allows the ultimate in precision to prepare the donor and the patient for corneal transplantation. This allows the surgeon the more accurately place the graft. The laser is accurate to within microns so the donor and recipient can be extremely accurately matched for shape and size. The benefits are in a more rapid rehabilitation, with less astigmatism and a stronger wound structure. At LaserVision, laser assisted corneal transplants (FsDALK) are now routinely offered to all suitable patients.

 

Full Thickness Surgery

Penetrating Keratoplasty (PK)

Occasionally it is not possible to perform a DALK. This may be due to technical reasons during surgery, or because the disease in the cornea is too deep and involves the inner layers of the cornea. In these cases a PK or full thickness corneal transplant will be performed. These have been performed for over 100 hundred years, and also offer excellent visual potential.

Femtosecond Laser Assisted Penetrating Keratoplasty (FsPK)

At LaserVision, Femtosecond Laser Assisted Penetrating Keratoplasty is now also available. It offers the same advantages as laser assisted DALK. The graft is more accurately positioned, and the size and wound construction can be matched within microns, providing more rapid healing stronger wounds and reduced astigmatism.

 

 

Surgery FAQs

 

What actually takes place during the operation?
Corneal transplant surgery for keratoconus is usually performed under general anaesthetic (the patient is asleep) but can be performed whilst the patient is awake. A central disc of cornea (approximately 7 to 8mm across) is carefully removed from the patients eye. It is replaced with a matching disc of tissue is taken from the donor cornea (this is the corneal graft), and stitched into place with very fine nylon stitches.

 

How long does the operation take?
A full thickness corneal graft or “penetrating keratoplasty” takes about an hour. Partial thickness or “deep lamellar keratoplasty” takes one-and-a-half to two-and-a-half hours. If any other surgery is planned, such as cataract surgery, then it will take longer.

For laser assisted surgery,the surgery is performed in two stages on the same day. The laser incisions are performed in the laser suite. This only takes a few minutes and is performed under local anaesthetic. The patient is transferred to the operating theatre where the rest of the operation is performed under general anaesthetic.

 

How long will I be in hospital?
Usually you will come in on the day of surgery with the operation scheduled for first on the operating list. You will almost always be able to go home later that same day.

 

What will it feel like after surgery?
Your eye will feel irritable and gritty and probably still blurred in the first week or two, and it might be slightly painful. If you are working we advise at least two weeks off work. After the first 24 hours severe pain should not occur – if it does you should contact the eye clinic.

The improvement in vision will depend on what the vision was like before the graft. Many eyes undergoing corneal graft are very blurred, and so there is often a slight to moderate improvement even after the first few days. However, as the cornea heals relatively slowly, it may take a few months before the vision improves significantly, so patients have to be patient.

 

Will I need drops after the operation?
Yes. Initially an antibiotic drop four times a day for about 2 weeks, and also a steroid drop four times a day. Steroid eye drops are very important to prevent rejection of the graft and they are used for a year or more. However by the end of the year they are only put in once a day. It is vitally important not to run out of steroid drops.

 

How often will I need to be seen after the operation?
You will be seen a day or two after the day after the operation. Your next visit is usually one or two weeks later. We then increase the period between visits, often to four weeks, then three months etc. This will depend on each individual.

You can expect to be seen at least six times in the first year. It is likely that you will need to be seen once or twice a year for the first few years.

 

Is there anything I should avoid after the operation?
You can do most things, but try not to bump the eye. Swimming pools are an infection risk, so avoid swimming for a month. It is safe to fly, unless you have been told that air has been used inside the eye during the operation.

 

Could I catch any disease from the transplant?
The medical history of the donor is checked to exclude the following conditions: rabies, Creutzfeldt-Jakob disease [CJD] and diseases of the nervous system of unknown cause. Blood is taken from all donors to exclude hepatitis B, hepatitis C and HIV. While the cornea is in the Eye Bank in Bristol it is very carefully examined to reduce the risk of infection with bacteria and fungi; as a result of these checks the risk is tiny (much less than 1%). However, because of this tiny risk, once you have had a corneal transplant you will not be able to be a blood or organ donor.

 

How well will I see?
Visual recovery is slow and varies from patient to patient. The eye can be shortsighted, longsighted, or have significant astigmatism leaving the vision blurred. Vision can be corrected using glasses, or sometimes even a contact lens. The majority of patients over 80% of patients will obtain legal driving vision in the eye after the transplant.

Alternatively patients can undergo further smaller procedures such as refractive laser surgery to improve the vision if required.

 

Why and how are the corneal stitches removed?
The stitches used do not dissolve, as this would lead to them disappearing too soon. If left in forever they will eventually become loose and irritate. Depending on how the eye is settling the sutures are usually removed between 6 months and 2 years. They are usually removed in the operating theatre, but it is a simple procedure. It takes about 20 minutes, with the eye anaesthetised simply with drops.

Occasionally a stich comes loose before this time, it will feel irritating, and is best removed as soon as possible in the clinic.

 

How long will the graft last?
Deep Anterior Lamellar Graft (DALK)

One of the great benefits of a DALK is that it will usually last for the patients life time.

Penetrating Keratoplasty (PK)

Penetrating keratoplasty (PK) may not last as long but usually last 10 to 20 years. But if a PK fails it is quite possible to repeat the procedure. If a penetrating keratoplasty fails it will become cloudy giving misty vision. The most common cause for failiure of the cornea is loss of the endothelilal cells on the inner surface of the cornea. These can be lost naturally and slowly over time or more rapidly in the case of corneal graft rejection. If this leads to loss of a critical number of cells the graft will fail and vision will become misty. Some eyes carry more risk than others. For example, an eye grafted for keratoconus has a better prognosis than one grafted for herpes simplex keratitis scarring. The 5 and 10-year survival for a full-thickness graft for keratoconus is 97% and 92% respectively. For all full-thickness corneal grafts it is 90% and 80%. The figures are much better for deep lamellar grafts.

 

Trauma risk
A grafted cornea remains structurally weaker forever. A graft can be ruptured from a blow to the eye. Therefore contact sports such as football are very risky indeed, and even less risky sports like tennis, squash should not be played without good eye protection. A ruptured graft can be disastrous for the eye and lead to blindness.

 

What problems should I seek advice about?
Graft rejection is the main concern (much less common in lamellar grafts). This rejection results from your immune system recognising the graft as being “foreign”. The eye becomes red, sore, sensitive to light, and the vision becomes blurred. This is very treatable, but if not treated early, can lead to permanent graft failure with blurred vision. Sometimes a stitch becomes loose and it feels like something is in the eye. This also needs to be dealt with quickly as a loose stitch can provoke rejection.

 

If you experience any of these symptoms please contact the clinic where you are looked after. DO NOT WAIT UNTIL YOUR NEXT APPOINTMENT.

Because each patient is different the above information is a general guide only. A corneal graft can be very successful in restoring reduced vision, but should not be undertaken lightly, and involves a great deal of responsibility from both the patient and the doctor.

 


Your LaserVision consultant surgeon can expertly guide you through the best treatments for you. Each treatment is personalised to achieve the best results.



In association with:
Sheffield Teaching Hospital NHS Foundation Trust, Greater Manchester University Hospitals NHS Foundation Trust