Photothrombosis in choroidal melanoma mediated by indocyanine green

Introduction
To assess the distant results of choroidal melanoma treatment with indocyanine green induced photothrombosis (iMP).

Material and methods
The study comprised 57 patients (57 eyes) at the age 39 to 68 yrs (mean age: 57.4 yrs), with choroidal melanoma. In all cases basic ophthalmic examination with ultrasonography and indocyanine green angiography (ICGA) were performed. IMP was performed with diode laser at 810 nm wave length 15 minutes after intravenous indocyanine dye injection as a bolus (50 mg/ 5ml). The main criteria for assessment of treatment efficacy included changes in tumor thickness measured by ultrasonography and microcirculation changes in ICGA. The follow-up period ranged from 37 to 59 months (mean: 45.5 month).

Results
Before iMP plaque therapy with 106Ru was performed in 18 eyes, and with 125I in 5, transpupillary thermotherapy (TTT) or xenon arc photocoagulation was used in 5 eyes and „sandwich method” (106Ru + TTT) in 16 eyes. Only in 13 eyes the primary treatment consisted of iMP. IMP was performed twice in 4 patients and three times in 2. After iMP the total regression of tumor microcirculation was observed in 36 cases, in 14 the partial regression was noted and in 7 the inner microcirculation remained unchanged. Ultrasonography showed the mean reduction of tumor thickness by 47.3% in 37 eyes, among which the flat scar was present in 12. Stabilization was observed in 15 cases while in 5 the further progression of the tumor was detected in spite of performed therapies. The additional treatment was performed in 20 cases. Six eyes was enucleated; in one case because of neovascular glaucoma, and in 5 because of no positive reaction to performed conservative treatment.

Conclusions
IMP can be an effective method of therapy in some cases of small choroidal melanoma. In medium size and in large melanomas iMP can serve only as the additional method adjunctive to plaque therapy and TTT.