Assessment of central vision and macular structure in patients undergoing iodine-125 brachytherapy for ciliochoroidal melanoma.

ABSTRACT

OBJECTIVES: To prospectively report standardized visual function and macular structural assessment in patients undergoing iodine-125 brachytherapy for choroidal and ciliary body melanoma. MATERIALS AND METHODS: Patients were enrolled for pretreatment and annual posttreatment assessment. Evaluations included ophthalmic history; standardized refraction; visual acuity, contrast sensitivity, and color vision measurement; comprehensive ophthalmic examination; fundus photography; fluorescein angiography; optical coherence tomography; and ultrasonography. Radiation doses to the foveola and optic disc margin were calculated. RESULTS: Forty-two patients were enrolled. Melanoma location included 3 in the ciliary body, 7 anterior, 11 equatorial, 13 posterior, and 8 macular tumors. Mean apical tumor height was 4.45 mm (range 1.79-9.83 mm) and mean longitudinal tumor diameter was 9.41 mm (range 4.52-4.73 mm). Pretreatment mean best-corrected Ferris-Bailey early treatment diabetic retinopathy study visual acuity was 50 (standard deviation +/- 15) letters (Snellen equivalent 20/32, range 20/15 to hand motions). The mean Pelli-Robson contrast threshold percentage was 4.1% (+/- 2.5%). The mean Hardy-Rand-Rittler color vision score was 13/14 (+/- 2.7). Mean distances from the posterior edge of the tumor to the foveola and the optic disc margin were 6.99 mm (+/- 6.22 mm) and 7.28 mm (+/- 5.98 mm), respectively. At the foveola, median total radiation dose was 36.2 Gy (+/-50.6 Gy) and median dose rate was 31.6 cGy/h (+/- 39.8 cGy/h). At the optic nerve, median total radiation dose was 42.8 Gy (+/- 30.8 Gy) and median dose rate was 36.2 cGy/h (+/- 21.4 cGy/h). CONCLUSION: This prospective assessment of macular structure and function will provide more complete understanding of the ocular effects of radiation therapy for ocular melanoma.