Abstract
Purpose::
To evaluate the anatomic and visual outcomes in patients undergoing photocoagulation treatment for proliferative radiation retinopathy (PRR) and clinically significant radiation macular edema (CSRME).Background: Radiation retinopathy (RR) is a sight-threatening complication of radiotherapy for diseases of the eye, ocular adnexa, sinuses, and brain. RR can manifest a variety of features resembling diabetic retinopathy (DR) for which photocoagulation treatment has been shown to be beneficial, both anatomically and visually.
Methods::
Retrospective chart, fundus photograph, and fluorescein angiogram review of 16 patients (22 eyes) who underwent panretinal photocoagulation (PRP) for PRR or focal laser treatment for CSRME. Inclusion criteria were history of radiotherapy around the eye and retinal findings of RR (retinal microaneurysms, hemorrhages, exudates, nerve fiber layer infarcts, macular edema and/or neovascularization), findings which are also present in DR. Examination methods included best-corrected visual acuity, anterior segment and fundus biomicroscopy, fundus photography, and fluorescein angiography. Indications for laser photocoagulation were the same as those for DR and included high risk characteristic(s) for severe vision loss (e.g., neovascularization of the optic disk plus vitreous hemorrhage) and macular edema involving or threatening the center of the macula (e.g., hard exudates at or within 500 microns of the center of the macula if associated with thickening of the adjacent retina).
Results::
Sixteen patients (22 eyes) were treated with photocoagulation. One patient (2 eyes) was treated with PRP, 5 patients (8 eyes) received PRP as well as focal laser treatment, and 10 patients (12 eyes) were treated with focal treatment only.Median visual acuities were 20/100 (with a range from 20/30 to LP) before treatment, 20/200 at the initial assessment, and 20/235 at the last follow up. The initial assessment occurred at 4 months (median) with a range from 2 to 7 months. Patients were followed for 2 to 251 months (median 78 months) after the procedure. Seven eyes were legally blind (20/200 or worse) prior to photocoagulation treatment, 5 additional eyes became legally blind despite the treatment, and only one eye had improved vision. Most treated eyes had responded anatomically with partial or complete regression of new vessels and decreased or resolved CSRME.
Conclusions::
Vision loss is a frequent complication of PRR and CSRME. Photocoagulation treatment is effective in decreasing neovascularization and macular edema due to radiotherapy but seldom results in improved vision. More effective prevention and treatment methods are needed to decrease vision loss from RR.
Keywords: radiation therapy • retina