Objectives: (1) To summarize the protocol used for grading features of postradiation abnormalities from fundus photographs and fluorescein angiograms of patients enrolled in the Collaborative Ocular Melanoma Study (COMS); (2) to document the prevalence of features of interest in the posterior pole of these eyes during 8 years of follow-up; and (3) to investigate baseline patient, tumor, and treatment characteristics associated with posterior pole features.
Design: Observational case series within a randomized, multicenter clinical trial.
Participants: We evaluated 650 patients who were assigned to and received iodine-125 brachytherapy in the COMS for medium-sized tumors.
Methods: Color fundus photographs and fluorescein angiograms were taken at baseline and 2, 5, and 8 years; 30 features were graded according to a standard protocol.
Main outcome measures: Prevalence at selected time intervals of fundus photographic features associated with retinopathy and optic neuropathy.
Results: The percentage of patients with >/=1 feature of interest was 49.2% at baseline, 84.4% at 2 years, 91.2% at 5 years, and 90.7% at 8 years. The most frequent findings across all follow-up examinations were macular microaneurysms (75.6% of examinations), macular angiographic leakage (75.1%), and optic disc hyperfluorescence (62.8%). The median number of features present increased significantly with each follow-up to a maximum of 7 features at 8 years. The prevalence of neovascularization of the disc at 5 years was 5.2%. The prevalence of optic neuropathy at 5 years was 27.4%. Prognostic factors for more prevalent and severe posterior pole abnormalities were diabetes, tumor location close to both optic nerve and foveal avascular zone, and greater dose of radiation to the foveola and optic nerve head.
Conclusions: The amount and severity of retinopathy and optic neuropathy after iodine-125 brachytherapy increased through 8 years of follow-up. Assessment of photographs and angiograms taken in accord with a standard protocol provided reliable estimates of rates of development of features of retinopathy and optic neuropathy in eyes treated using the COMS brachytherapy protocol. Our findings support earlier reports that tumor factors in addition to radiation treatment may contribute to posterior pole abnormalities.
Financial disclosure(s): The authors have no proprietary or commercial interest in any materials discussed in this article.
Trial registration: ClinicalTrials.gov NCT00000124.