05.10.2018 change 05.10.2018

Polish ophthalmologists performed the most corneal repair procedures with an innovative method

Photo: Fotolia Photo: Fotolia

Polish ophthalmologists performed the highest number of damaged cornea repair procedures with a method that uses the patient`s own stem cells, experts said during the "Autumn Ophthalmic Workshop 2018" in Jachranka near Warsaw.

Stem cell transplants of corneal limbus are performed as part of a clinical trial by the team led by Prof. Edward Wylęgała, head of the Clinical Ophthalmology Department of the Medical University of Silesia in Katowice. The professor himself emphasised that so far they had been performed in 10 patients, including one child. "It`s the highest number in Europe (for now, the method is used only in European countries - PAP). Among these 10 patients we have one failure, but we can repeat the procedure" - the specialist said during the meeting, which ended last weekend.

He explained that transplantation of corneal limbal stem cells is a method used to restore vision in patients who have corneal epithelial damage in their eyes, most often due to chemical burns (for example contact with lime) or thermal burns. They are patients, in whom the corneal epithelium cannot regenerate spontaneously due to damage to the corneal limbal stem cells (corneal limbal stem cell failure). In this situation, the cornea loses transparency and the patient - the ability to see. Other indications for the use of this method include congenital eye diseases, such as congenital absence of the iris (aniridia) or sclerocornea.

If one eye is damaged, stem cells can be taken from the healthy eye. But even if the damage affects both eyes, a small portion of preserved healthy corneal limbus will suffice to use the innovative treatment method. The method itself was developed by Italian scientists led by Prof. Grazielli Pellegrini from the University of Modena and Reggio Emilia (Universita degli Studi di Modena e Reggio Emilia). It involves taking 1-2 mm2 of a healthy corneal limbus. The cells present in it are then transported by land (air transport is not possible because it could harm the cells) to the laboratory in Modena, Italy, where they are cultured for about six months. The goal is that about 3 percent of the cultured cells should be stem cells of the corneal limbus. This guarantees that they will continue to regenerate the corneal epithelium for the entire lifetime of the patient, and the treatment effect will last.

The cell culture is then transported in a special packaging to the centre, in which the patient is to be treated. The cells are transferred to the surface of the eye on a special transparent fibrin (a natural connective tissue protein) medium. Then the eye is closed for four or five days. No topical medicines are used. Enzymes present in tears digest the fibrin matrix and the corneal epithelium settles on the surface of the eye. On the fourth day after the surgery the eye is exposed.

"This is an advanced drug therapy technology. When we think about a drug, we usually imagine a tablet, capsule, ampoule, ointment, drops. Now we have a drug in the form of stem cells, enclosed in a metal packaging. The active substance in this case are stem cells that will regenerate the cornea for the rest of the patient`s life" - explained Prof. Wylęgała.

According to Dr. Dariusz Dobrowolski from the Clinical Ophthalmology Department of the Medical University of Silesia in Katowice, the advantage of this method is that the patient receives his own cells. "In the case of corneal transplants from a deceased donor, some patients require the administration of immunosuppressants, such as cyclosporine, which can damage the kidneys" - said the specialist.

He stressed that the effectiveness of the new method was very high. "One of my patients recently told me that he basically returned to normal activity and his vision improved so much that he even stopped using moisturizing drops. He does not feel pain, burning, there is no fibrosis" - said Dr. Dobrowolski.

He noted that the cost of treatment with the new method was high. It is estimated at about 92,000 euros for one patient. In Poland, there is a need for about 50 such treatments per year.

National ophthalmology consultant Prof. Marek Rękas told PAP that he wrote a letter to the Minister of Health regarding reimbursement of this therapy. "We would very much like to be able to use this method in patients with corneal stem-cell deficiency" - he said. He also noted that this therapy was very expensive. Its use, however, can be justified from an economic point of view, because a patient who regains the ability to see well can function normally in society and return to work, he said.

Dr. Dobrowolski told PAP that further patients are now qualified for the procedure, for example a girl struck with a pencil in the eye by her brother. This caused a corneal puncture and damage to the lens. An artificial lens was implanted in Wrocław, but the girl has a large corneal scar. "She qualifies for this method and will have a transplant done within a month" - he said.

Experts noted that there were several contraindications for corneal limbal stem cell transplantation. According to Prof. Wylęgała, that they include a lack of corneal sensation associated with damage to the innervation of the cornea. This makes the treatment rather unlikely to have a beneficial effect in the form of regaining vision. Similarly, when there is damage to the optic nerve.

Professor Wylęgała emphasized that Italian authors of the innovative method of corneal epithelium repair were already planning a new study. Patients with bilateral eye injury and corneal stem-cell deficiency will be eligible. In their case, the stem cells to rebuild the corneal epithelium will be extracted from the oral mucosa. The study will be conducted in Milan and in Poland by Prof. Wylęgała`s team.

The pioneer of this method is Dr. Dariusz Dobrowolski. "We were the first in the world to publish a scientific paper on the subject. But we still have a problem with the implementation of innovative methods in Poland" - emphasised Prof. Wylęgała.

PAP - Nauka w Polsce, Joanna Morga

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