Abstract
Purpose :
Radiation retinopathy is a frequent cause of vision loss after iodine-125 (125I) plaque brachytherapy in the treatment of uveal melanoma. Vitrectomy with silicone oil (SO) 1000 centistokes placement has been shown to decrease radiation retinopathy in large uveal melanoma due to radiation attenuation of SO. We analyzed the outcome of 125I brachytherapy with vitrectomy and SO placement in the treatment of small uveal melanoma with apical height <3 mm.
Methods :
This was a retrospective case-control study including 36 patients treated with 125I plaque brachytherapy and vitrectomy with SO placement and 29 control patients treated with 125I plaque alone. Patients received routine post-op ocular and systemic surveillance including dilated fundus exam, B-scan, and Optos widefield fluorescein angiography to assess for radiation retinopathy at 6, 12, 24, and 36 months. Radiation retinopathy severity was graded based on evidence of foveal and peripheral leakage, non-perfusion, and retinal neovascularization using a validated 4-point scale. The impact of SO placement on radiation retinopathy, visual acuity and metastasis was reviewed at 3 years post plaque treatment.
Results :
Twenty-seven case patients (mean age 61, 59% female) and 15 control patients (mean age 61, 40% female) were available for analysis at 3 years post plaque. Mean tumor height was 2.23 mm in controls and 2.43 mm in cases (P=0.08). The final logMAR VA was 0.86 in cases and 0.38 in controls (P = 0.03); the change from pre-treatment to final logMAR was 0.76 in cases and 0.2 in controls (P = 0.006). The proportion of eyes with each grade of retinopathy was similar between groups (P = 0.99). All 42 eyes achieved local tumor control without distant metastasis.
Conclusions :
125I brachytherapy for small uveal melanoma is effective in achieving local tumor control. In contrast to treatment of large uveal melanoma, combining brachytherapy with vitrectomy and SO for radiation attenuation did not significantly improve vision over the use of plaque alone. SO placement for 125I radiation attenuation in small tumors may not yield additional visual or angiographic benefit at 3 years post brachytherapy.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.