Purpose

Non-invasive tests to detect early symptoms of radiation maculopathy (RM) are of primary concern of recent research. This will allow identification of a group of patients who are particularly at risk of vision loss due to developing complications as well as treatment evaluation. The aim of the study was to retrospectively evaluate the early optical coherence tomography (OCT) biomarkers of RM and review the final VA outcomes at 5-year follow-up post-ruthenium brachytherapy for uveal melanoma (UM).

Material and methods

Medical charts of 135 UM patients who underwent brachytherapy between 2013 and 2019 were reviewed. Central retinal thickness (CRT), presence of intraretinal cysts, biggest cyst diameter, and presence of hyperreflective foci (HRF) were verified on OCT scans retrospectively at 6, 12, 18, 24, 36, and 60 months post-treatment.

Results

There were 135 patients: 78 women and 57 men, with a median age of 61 years. The median follow-up was 55 months (range, 7-123 months). RM occurred in 63 patients (46.67%) in a median time of 24 months post-treatment. The occurrence of RM correlated with radiation dose to the sclera and tumor apex, tumor size, and distance from the fovea (p < 0.05). The presence of cysts and HRF, both inflammatory and exudative types, correlated with RM over time (p < 0.05), and were the strongest biomarkers of radiation damage. The mean final VA on Snellen chart at 5 years post-treatment was 0.48.

Conclusions

The most important risk factors for RM are tumor size, plaque dosimetry, and distance to fovea. The presence of HRF and cysts is of the greatest diagnostic value, as they are the first OCT signs of RM.