What does it involve?
Brachytherapy is radiotherapy treatment at close range. It involves placing a radioactive source in contact with the surface of the eyeball with ruthenium-106 or iodine-125, which are radioactive isotopes.
When is it carried out?
The treatment is used for malignant intraocular tumours, such as choroidal melanomas, retinoblastomas and intraocular metastasis. Brachytherapy can also be indicated for cases of vascular tumours, such as retinal capillary angiomas and cavernous angiomas.
In the case of choroidal melanoma treatment, it is very important to find out the condition of the liver, because, if metastasis occurs, 90% of cases affect the liver. Liver function is checked by means of tests and a liver ultrasound. A CT scan should also be carried out to detect for tumours throughout the body. The scan uses a contrast technique to detect for tumours that are larger than 5 mm.
Before the surgery
In the case of choroidal melanoma treatment, it is very important to perform a comprehensive examination of the condition of the liver.
During the procedure, the conjunctiva is dissected and, by means of transillumination or marking systems while observing the fundus, the tumour can be precisely located and the radioactive ruthenium or iodine plaque, which is prepared exclusively for the patient, can be positioned. These plaques are covered by a layer of silver or gold to ensure that the radiation is applied to the interior of the eyeball, preventing it from spreading outwards. The plaque is implanted with a certain dose of radiation that lethally damages the tumour cells, which, over the following months, atrophy and leave tumour-free scar tissue.
There are no significant risks to take into account.