Radiotherapy for recurrent choroidal neovascularisation complicating age related macular degeneration
- 1Department of Ophthalmology, Medical College of Georgia, Augusta, GA, USA
- 2Department of Radiology, Section of Radiation Oncology, Medical College of Georgia, Augusta, GA, USA
- 3Office of Biostatistics, Medical College of Georgia, Augusta, GA, USA
- 4Department of Ophthalmology, University of Pennsylvania Health Systems, Philadelphia, PA, USA
- 5Ocala Eye Surgeons, Ocala, FL, USA
- Correspondence to: Dennis Marcus, MD Medical College of Georgia, 1120 15th Street, Augusta, GA 30912, USA; dmarcusmail.mcg.edu
- Accepted 1 August 2003
Abstract
Aims: To report the safety and visual outcome data of external beam irradiation for recurrent choroidal neovascularisation complicating age related macular degeneration.
Methods: Eighteen consecutive eyes received external beam irradiation with seven fractions of 2 Gy (total dose 14 Gy). The next 16 consecutive eyes received external beam irradiation with five fractions of 3 Gy (total dose 15 Gy). Main outcome measure was change in visual acuity. Secondary outcome variables were contrast sensitivity and fundus photographic/fluorescein angiographic progression.
Results: The 3 Gy fraction group lost fewer lines of distance visual acuity at the three and six month follow up. At one year follow up, this difference was not maintained with 2 Gy fraction and 3 Gy fraction eyes. At one year follow up a decrease in visual acuity of three or more lines (moderate visual loss) occurred in 58% of 2 Gy and 42% of 3 Gy fraction eyes (p<0.36). At one year follow up a decrease in visual acuity of six or more lines (severe visual loss) occurred in 41% of 2 Gy eyes and 17% of 3 Gy eyes (p<0.23). At three months follow up, 3 Gy eyes were less likely (0%) than 2 Gy eyes (47%) to show moderate visual loss (p<0.003). However, Kaplan Meier curves estimate a significantly lower rate of severe visual loss in the 3 Gy group (p = 0.02). There were no significant differences in contrast sensitivity loss or fluorescein angiographic stabilisation rates. No evidence of radiation toxicity was observed.
Conclusion: Our results are consistent with trends for a palliative benefit with higher fraction sizes and doses. The radiobiologic differences between low and high fraction size groups in this study are modest and correlate with the modest and short term difference in visual outcomes. These trends support further investigation of radiotherapy using fraction sizes of 4 Gy or higher.
- choroidal neovascularisation
- age related macular degeneration
- radiotherapy
- external beam irradiation







