Iatrogenic choroidal neovascularisation following argon laser photocoagulation for choroidal malignant melanoma

Choroidal neovascularisation is known to occur following photocoagulation for choroidal melanomas. Its occurrence rate, possible causes and clinical impact were studied.

Post-treatment fluorescein angiograms were reviewed from 18 patients who had received argon laser photocoagulation as sole treatment of their small choroidal melanomas, to look for choroidal neovascularisation. Where it was found an assessment of its clinical impact was made.

choroidal neovascularisation was found in 50% of cases. Choroidoretinal neovascularisation, found in five patients, caused vitreous haemorrhage in one patient but was otherwise benign. Choroidovitreal neovascularisation was found in four patients. It occurred early and altered their clinical management. Three of these patients had a vitreous haemorrhage, one of whom also suffered a retinal detachment. The three diabetic patients in the series all developed aggressive choroidovitreal neovascularisation. Tumour size, tumours location and number of treatment sessions did not appear to affect the occurrence of choroidal reovascularisation, nor did other medical or ocular conditions except for diabetes.

Choroidal neovascularisation occurs commonly after melanoma photocoagulation. Although sometimes benign, it can be aggressive, particularly in diabetic patients, in whom it might be better to consider different forms of tumour treatment.