Abstract
Purpose: :
To assess patient visual and survival outcomes following the treatment of juxtapapillary choroidal melanomas with notched Iodine 125 radioactive plaques.
Methods: :
This retrospective review examined the clinical outcomes of 7 consecutive patients (7 eyes) with choroidal melanomas that were located within 1 mm of the optic disc and were treated with a notched radioactive plaque at the University of South Florida Eye Institute.
Results: :
The average length of follow-up was 47 months (range: 24-78). In each patient, the tumor height decreased throughout the length of follow-up, as documented by clinical examination and B-scan ultrasound. No patients experienced local tumor recurrences, displayed evidence of metastatic disease, or died throughout the length of follow-up. The visual acuity severely declined in 3 eyes (43%), remained excellent in 3 eyes (43%), and maintained vision at the counting fingers level in 1 eye (14%). Evidence of radiation retinopathy occurred in all eyes (100%), an average of 1.7 years after treatment. Radiation optic neuropathy occurred in 5 eyes (71%), an average of 2.7 years after treatment. Eyes that did not experience radiation optic neuropathy had tumors located further from the optic disc and had been administered one half of the average dose of radiation to the optic nerve compared to those eyes that developed radiation optic neuropathy. Visual acuity severely decreased (> 6 lines) in three eyes (43%) throughout the length of follow-up, which was directly attributed to radiation optic neuropathy.
Conclusions: :
The use of notched radioactive plaques to treat juxtapapillary choroidal melanomas continues to be an effective method of local tumor control. However, the proximity of the radiation treatment to the macula and optic nerve places the patient at very high risk for severe vision loss due to radiation side effects. The risk of radiation optic neuropathy was greatest for eyes with tumors directly in contact with the optic disc and those receiving large doses of radiation. The risk of losing vision, as well as the time frame in which the vision will likely decline, must be thoroughly discussed with patients prior to utilizing this eye conserving treatment strategy for melanomas near the optic disc.
Keywords: choroid • melanoma • radiation therapy