Custom-made "Nag" eye plaques for 125I brachytherapy

Area of Science:

• Ophthalmology
• Radiation Oncology
• Medical Physics

Background:

• Ocular melanoma treatment requires precise radiation delivery.
• Custom eye plaques offer tailored radiation therapy for intraocular tumors.
• The "Nag" plaque is a specific design for brachytherapy.

Purpose of the Study:

• To evaluate the efficacy of custom-made "Nag" eye plaques for treating medium-size ocular melanomas.
• To assess survival rates, visual acuity, and complications associated with this treatment modality.
• To determine the optimal margin size for plaque placement.

Main Methods:

• Seventy-eight patients with medium-size ocular melanomas were treated using custom 18k gold "Nag" plaques.
• Plaques were designed to cover the tumor base with a 1-mm margin and secured with sutures.
• Iodine-125 ((125)I) delivered 100 Gy (pre-TG-43) or 85 Gy (post-TG-43) over 4 days, prescribed to the tumor apex periphery.

Main Results:

• At a median follow-up of 49 months, 5-year progression-free survival was 93%, overall survival 86%, and disease-specific survival 97%.
• Useful visual acuity (≥20/200) was retained in 64% of patients.
• Retinopathy or papillopathy occurred in 40% of patients, with higher rates (54%) and poorer visual outcomes in those with tumors ≤2 mm from the optic disc or macula.

Conclusions:

• Custom-made "Nag" plaque brachytherapy demonstrates effective local control for medium-size choroidal melanomas.
• A 1-mm margin appears sufficient with this technique, potentially reducing the need for larger margins.
• Tumor proximity to the optic disc or macula significantly correlates with adverse visual outcomes and complications.