Abstract
Purpose:
Radiation maculopathy is a common, vision threatening complication of plaque radiotherapy in the management of uveal melanoma. It is reported that intravitreal bevacizumab (IVB) injections might be effective in the management of radiation maculopathy. However, the treatment regimen and long term results are not known. In this study, we evaluated long-term effects of IVB in the management of radiation maculopathy.
Methods:
A retrospective review of patients who received IVB for radiation maculopathy from October 2010 through October 2012 was performed. The patients received monthly injections for 3 months, followed by injection intervals adjusted to every 2 or 3 months depending on patient response. Patients were evaluated by visual acuity (VA), status of radiation maculopathy, and macular thickness on optical coherence tomography (OCT). Student's t-tests were used to compare observations.
Results:
A total of 17 patients were included into the study. An mean of 4.25 injections were given per patient over a mean of 195 days. All patients experienced vision loss documented on Snellen chart prior to therapy. The mean VA on the day of first injection was 0.78 logMAR. Following injection, vision loss was stabilized with no significant change in VA on first follow up (VA=0.77, 41 days after 1st injection), second follow up (VA=0.80, 86 days), or third follow up (VA=0.78, 186 days) (all p-values < 0.05). When injections were spaced longer than two months apart, VA was negatively affected. Patients who received repeat injections within eight weeks of the previous injection (n=44) demonstrated a mild improvement in visual acuity when compared to vision at time of the last injection (-0.02 change in logMAR) while patients who received the repeat injections longer than eight weeks (n=40) had significantly more vision loss (+0.12 logMAR, p=0.01). The mean central macular thickness obtained from OCT at initial IVB treatment was 377 μm. Follow up OCTs were obtained an average of 71 days after first IVB injection and showed a significantly decreased mean macular thickness of 310 μm (p=0.048).
Conclusions:
IVB seems to be effective in the management of radiation maculopathy by preventing further visual loss. Eight-week intervals between injections seems to give the best visual acuity result. Identifying factors that lead to treatment success will be essential for future therapy.
Keywords: 671 radiation therapy •
589 melanoma •
585 macula/fovea