The most common malignant tumour in the eye is melanoma of the choroid. In Hungary, the Ophthalmology Clinic of the University of Debrecen Clinical Centre has been a national centre for the diagnosis and treatment of these tumours. It was and is the only place in the country where it was and is still possible to treat choroidal melanoma with the retention of the eyeball using an applicator containing the beta radiation isotope Ruthenium-106, referred to as brachytherapy.
The new, complex treatment, which requires targeted radiosurgery and special surgery, was first performed last December at the Ophthalmology Clinic of the University of Debrecen Clinical Centre. The radiosurgery is performed the week before the surgery, after special imaging and planning.
- First the tumour is destroyed using external radiation. After a CT scan and MR scan for planning, a computer program is used by the radiotherapist and physicist to plan how the linear accelerator can best deliver the right dose of radiation to destroy the tumour tissue but minimise radiation exposure to surrounding tissues. Because cell death would trigger an inflammatory response that would effectively destroy the eyeball itself, to avoid this, the tumour tissue is removed from the inside of the eyeball by the retina surgeon the day after the radiation treatment," Mariann Fodor, Director of the Ophthalmology Clinic explained.
During retinal surgery, the tumour tissue from the choroid is removed along with the overlying nerve membrane.
- These tumours are about fifteen millimetres in diameter, while the diameter of the whole eyeball is about twenty-four millimetres, which means that there is a fairly large gap in the retina and choroid compared to the eye. Under these circumstances, it is a challenge to re-install the neural membrane, which has been completely detached by the tumour and the radiotherapy, in such a way that it remains permanently in place. Although pre-operative radiation significantly reduces the occurrence of bleeding, the removal of a tissue mass always results in bleeding, which impairs visibility during surgery. We try to avoid this by keeping blood pressure low during anaesthesia and by increasing intraocular pressure during surgery," said the director of the clinic.
The surgery is performed to avoid removing the eyeball, mainly so that the patient does not have to wear a prosthesis. The procedure requires considerable retinal expertise.
- This procedure was initially performed without radiation worldwide but it was discovered that the small size of the eyeball meant that the safety zone used to remove tumours was very small, and tumours often recurred after surgery. Without radiation, a very small number of such operations have already been performed in Hungary. Today this type of surgery is recommended to be performed in combination with radiation. This combined form was first introduced in Hungary at the Ophthalmology Clinic of the University of Debrecen Clinical Centre in December 2023 with the aim of reducing the number of patients who have to experience eyeball loss in the future," said Mariann Fodor.
The introduced combined therapy is complex and requires complex organisation between the clinics, therefore the therapeutic steps are carried out by Professor Ervin Berényi, Director of the Medical Imaging Clinic, Professor Árpád Kovács, Head of the Oncological Clinic and Mariann Fodor, Associate Professor, Head of the Intraocular Tumour Department of the Ophthalmology Clinic, in collaboration with Éva Surányi, Clinical Specialist. The eye-preserving combined therapy of large ocular tumours in the eye is supported by the Ophthalmology Section of the College of Ophthalmology.
In order to learn radiotherapy and eye surgery, the specialists participated in a study visit to the University of Essen in the autumn of 2023, where around two thirds of eye tumours in Germany are treated.
Press Centre - CzA