Abstract
Abstract: :
Purpose:Evaluation of the results of Ruthenium 106 brachytherapy of iris and irido-ciliar melanomas using a new diagram for calculation of the radiation dose. Methods:A new designed anterior segment diagram was developed to perform a more precise calculation of the brachytherapy radiation dose for irido- ciliar melanomas with less anterior segment complications but still sufficient tumour reduction The melanomas in 20 eyes of 20 patients were divided in iris, irido-cilair and ciliar melanomas and analysed by biomicroscopical and ultrabiomicroscopical (UBM) measurements. From the twenty cases 6 iris, 9 iridociliar and 5 anterior ciliar melanomas were treated. In two patients (10%) 800 Gy, in twelve (60%) 500- 600 Gy, and six(30%) 400 Gy was prescribed. Results:After a follow-up of 6 to 60 months tumour reduction was seen in all cases as well clinical as with UBM. In one case the iris tumour vanished completely but after 16 months 180 degrees of the irradiated field a new melanoma of the iris was found and enucleation performed. Severe eye complications were found in the two cases treated with 800 Gy. In contrary the patients treated with 400-600 Gy demonstrated only minor complications. Cataract developed in 5 cases, in two cases however after phacoemulsification uveitis and cystoid macular oedema arised. Conclusion:Based on our anterior eye segment model local tumour control was achieved in iris and iridociliar melanomas with 400-500 Gy with less complications than in doses of 800 Gy. Ruthenium106 brachytherapy seems an alternative for enucleation or complicated iridocyclectomies with preservation of the eye and visual function.
Keywords: 464 melanoma • 538 radiation therapy • 447 iris