Are newer types of cornea transplants like Descemet Membrane Endothelial Keratoplasty or DMEK a safe and successful surgery?

The first question that comes to your mind as a patient is about this newer type of corneal transplant procedure and its benefits. Is this right procedure for you and what happens if it does not work?

So, to start addressing your concerns lets explain what type of transplant it is, its advantages and indications and the follow-up timeline.

DMEK as this procedure is popularly abbreviated and known is a relatively a new type of corneal transplant, which has gained the world’s attention for its excellent results and faster recovery as well as a significantly decreased risk of transplant related rejection.

The cornea has 5 layers, out of which the inner most layer is responsible for clarity of the cornea permitting an individual to see clearly. The cornea is the front layer of the eye and a clear cornea acts like a clear window or windshield. So, imagine if you were driving and looking at the road through a clear versus a hazy or cloudy windshield and that view would be the difference between a clear and not so healthy or clear cornea. Your view of what you can see could be severely compromised should the cornea become hazy as a result of disease. When the deepest layer inside the cornea gets damaged or gets compromised the cornea becomes hazy or cloudy and hence a. patient experiences a decrease in sight and vision is disturbed.

In DMEK, only the deeper layer of the cornea which is responsible for keeping the cornea clear is replaced. This inner lining of the cornea gets replaced with the same “endothelial” tissue which has been procured from a donated eye and pre checked for health, viability and is tested and found to be free of infection.

The main indications of DMEK are Fuchs Corneal Dystrophy (a hereditary disease of inner layer of the cornea) as well as Pseudophakic Bullous Keratopathy(corneal damage or decompensation usually after complicated cataract surgery or after other eye surgeries that may cause gradual deterioration or compromise of this inner layer of cells). Other common indications are for patient who previously had traditional full thickness corneal transplants that may have rejected or failed and any additional condition which affects the function of inner lining of corneal tissue.

DMEK Procedure and Follow-up 

DMEK is relatively quicker procedure, done under local anaesthesia. Operating time is roughly 45 minutes only. After completion of surgery, you need to lie flat on your back with a pillow under your neck to make you comfortable for approximately 2 hours and you will be seen approximately 60- or 90-minutes following surgery by the operating surgeon to ensure corneal graft attachment. Once the surgeon is confident of the desired position and placement of the corneal graft, you would still need to lie flat or looking up at ceiling while seated upright for usually another 30 to 45 minutes per hour for next day or so.

No stitches are placed or needed as we rely on achieving graft attachment using a bubble. Sometimes a stitch does need to be placed which is not felt by the patient and does not hurt and often is removed in clinic in a week’s time.

Patient cooperation is as important as the surgeon’s skill in performing the surgery and we encourage our patient to understand the procedure and follow post-operative instructions giving us as a team the best chance of recovery without needing further procedures.

About 10% of patients needs re-injection of air if the bubble placed at the time of surgery absorbs more quickly than expected leading to part of the graft not remaining fully attached. However, this is not serious and can easily be managed and requires a very simple procedure of injecting more air in the eye, depending on the size and location of graft detachment. This can be done in clinic or at theatre under anaesthetic drops and takes only 15 minutes.

DMEK is a very successful type of corneal transplant where 97% of the cases do very well   After recovery, you are expected to see better, and your vision can be improved to legal driving limits as early as 2 weeks after the procedure.

An important point to remember is this. Because the endothelial tissue is a donated corneal tissue, your body can sometimes fail to accept it which can lead to graft failure, or your body defence mechanism can overact and lead to graft rejection. However, even in the unlikely case that this should occur you do not need to be disheartened as many additional options exist. You can always have new donated tissue implanted and your sight can be restored to its maximum potential. 

Apart from risk of rejection or failure, rare chances of rise in intraocular pressure or swelling the back of eye known as the macula can result. These remain manageable and treatable.

Let us discuss post-operative visits or follow up visits.

After surgery you will need to be seen on the first day after surgery, then a week later, 3 weeks later. After this you will be re-examines at 1 month, 3 months, 6 months, 9 months and then finally once a year for at least 5 years.

Always remember, you are in safe and trained hands, and we thank you for your trust and aim to provide the best possible medical and surgical eye care for you.

Dr Muhammad Hamza is a consultant ophthalmologist and cornea & anterior segment surgery specialist at The Eye Center – Dr. Mahnaz Naveed Shah & Associates and South City Hospital, Karachi. Dr. Hamza holds an FRCS from the UK and has formal additional sub speciality fellowship training in the most modern techniques of cornea transplantation and all types of cataract, corneal and refractive surgery.

Dr. Hamza completed his MBBS in Karachi, following which he completed his ophthalmology training from Aga Khan University Hospital, Karachi. He was awarded M.R.C.S (Ed) and F.R.C.S (Ed) and later F.R.C.S (Glasgow).  He has trained at the prestigious corneal fellowship programs in the UK. Additionally, prior to returning to Pakistan, Dr. Hamza served first as senior corneal fellow in Southampton and Colchester and then, in recognition of his skill and expertise, served as a consultant at the world- renowned Kings College Hospital in London. Dr. Hamza continues to serve as a member of the Surgical Skills Faculty of the Royal College of Ophthalmologists, London, where he remains actively involved in the surgical training of ophthalmologists.

Dr. Hamza has been managing patients suffering from complex corneal disease, and regularly performs surgeries including, but not limited to, routine and complex cataracts, corneal grafts, and anterior segment reconstruction, including post trauma repair. He provides regular training and supervision to junior trainees within clinic as well as in the operating room.
Dr Hamza has lectured widely internationally and regularly participates and lectures at national and international meetings.  He has also authored several research papers for journals in multiple countries and is a contributing reviewer for Eye, the academic journal of the Royal College of Ophthalmologists, U.K. 

Dr. Hamza brings his experience of partial thickness corneal transplant to Pakistan and is extremely skilled in performing Descemet Membrane Endothelial Keratoplasty (DMEK) and amongst the only few who can perform Deep Anterior Lamellar Keratoplasty (DALK), Descement Stripping Automated Endothelial Keratoplasty (DSAEK) in addition to all routine corneal procedures.

Dr. Hamza is a great addition to our team of nine ophthalmologists at The Eye Center who are highly qualified and skilled eye specialists and eye surgeons and are considered as key thought leaders in their areas of expertise. His expertise is a most welcome addition for colleagues and patients alike.

For Appointments with Dr. Muhammad Hamza please contact us at  0304 1110302 829 1799, 0300  893 3377  1977, 0300 082 2218

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