Original article
Radiotherapy for subfoveal choroidal neovascularization in age-related macular degeneration: a randomized clinical trial

https://doi.org/10.1016/S0002-9394(02)01336-3Get rights and content

Abstract

PURPOSE: To report results of 18-month follow up of external beam radiation therapy with photons for subfoveal classic or occult choroidal neovascularization (CNV) in age-related macular degeneration (ARMD).

DESIGN: Randomized clinical trial.

METHODS: A total of 161 patients with subfoveal CNV in ARMD were recruited in a prospective double-masked study. The posterior pole of the afflicted eye was given 1 Gy (4 × 0.25 Gy) in the control group and 8 Gy (4 × 2 Gy) or 16 Gy (4 × 4 Gy) in the treatment groups. At the time of treatment, and 6, 12, and 18 months post treatment, best-corrected visual acuity (BCVA), reading ability, and CNV size were measured.

RESULTS: At the completion of the study 150 (93.2%), 139 (86.3%), and 137 (85.1%) patients were followed for 6, 12, and 18 months, respectively. The mean number of lines lost in the BCVA was −1.69, −2.2, and −3.23 in the 1 Gy group; −0.94, −1.25, and −1.73 in the 8 Gy group; −0.51, −0.67, and −1.93 in the 16 Gy group. The difference was significant after 12 months (P = .016 for 8 Gy vs. 1 Gy; P = .006 for 16 Gy vs. 1 Gy), and 18 months (P = .011 for 8 Gy vs. 1 Gy; P = .05 for 16 Gy vs. 1 Gy). The patients with classic CNV, or with an initial distance visual acuity ≥20/100, benefited more from treatment. A significant difference was not found between control group and treatment groups in the reading ability and in the CNV size. No radiation-associated side effects were reported thus far.

CONCLUSION: The number of lines lost in the BCVA was less in the 8 Gy and 16 Gy treatment groups than in the control group during the complete follow up examination. Radiation therapy with 8 Gy and 16 Gy, without showing any difference in efficacy, resulted in a near stabilization of the BCVA in patients with subfoveal classic or occult CNV in ARMD. Further studies are necessary to determine the significance of repeated radiotherapy series with a dose of 8 Gy to improve the effect on the CNV size and thereby to prolong stabilization of distance visual acuity.

Section snippets

Study design

The aim of our study was to report the results of an 18-month follow up of external beam radiation therapy with photons for subfoveal classic or occult CNV in ARMD.

The protocol for this prospective randomized double-masked study was approved by the Ethical Committee of the Kantonsspital St Gallen. The patients were informed in detail about their disease, the available therapeutic possibilities, and the study protocol of our investigation. Informed consent was obtained from each patient before

Patients and demographic data

A total of 161 patients were recruited. Classic CNV was diagnosed in 92 cases (57.1%), and occult CNV in 69 cases (42.9%). A total of 52 patients were randomly allocated to the control group with 1 Gy, 57 patients to the 8 Gy group, and 52 patients to the 16 Gy group. The main baseline characteristics of the patients are summarized in Table 1. Among the three groups no significant differences were present in the age and the gender of the patients, smoking habits, duration of the symptoms before

Best-corrected visual acuity

During the complete follow up, the mean number of lines lost was still less in the 8 Gy and 16 Gy groups than in the 1 Gy group. After 6 months, a positive trend was present in favor of 8 Gy and 16 Gy groups; a significant difference was present after 12 and18 months (Table 3). No significant difference in the number of lines lost was present between the 8 Gy group and the 16 Gy group during the complete follow-up examination (P = .800 after 6 months, P = .612 after 12 months, P = .461 after 18

Discussion

External beam radiation therapy in age-related macular degeneration has a long history in St Gallen and was previously performed by Bangerter and Hohl in the 1950s.33 After having treated, in a pilot study, the afflicted posterior eye of 40 patients with subfoveal classic or occult CNV with doses of 5 Gy (4 × 1.25 Gy) or 8 Gy (4 × 2 Gy),34 we started this prospective randomized double-masked study in 1994 and compared the efficacy of 8 Gy (4 × 2 Gy) and 16 Gy (4 × 4 Gy) with a control group of

References (45)

  • Photodynamic therapy of subfoveal choroidal neovascularization in age-related macular degeneration with Verteporfin. Two-year results of 2 randomized clinical trials—TAP report 2

    Arch Ophthalmol

    (2001)
  • Verteporfin therapy of subfoveal choroidal neovascularization in age-related macular degenerationtwo-year results of a randomized clinical trial including lesions with occult with no classic choroidal neovascularization—Verteporfin in photodynamic therapy report 2

    Am J Ophthalmol

    (2001)
  • Submacular surgery trials randomized pilot trial of laser photocoagulation versus surgery for recurrent choroidal neovascularization secondary to age-related macular degeneration

    Am J Ophthalmol

    (2000)
  • S Wolf et al.

    Macular translocation for surgical management of subfoveal choroidal neovascularizations in patients with AMDfirst results

    Graefes Arch Clin Exp Ophthalmol

    (1999)
  • P Algvere et al.

    Transplantation of fetal pigment epithelium in age-related macular degeneration with subfoveal neovascularization

    Graefes Arch Clin Exp Ophthalmol

    (1994)
  • R Du Bosar

    Age-related macular degenerationnew treatment shows promise

    J Ophthalmic Nurs Technol

    (1999)
  • R Newsom et al.

    Transpupillary thermotherapy (TTT) for the treatment of choroidal neovascularization

    Br J Opthalmol

    (2001)
  • A Haas et al.

    Gamma knife treatment of subfoveal classic neovascularization in age-related macular degenerationa pilot study

    J Neurosurg

    (2000)
  • M Raicu et al.

    Radiation damage to endothelial cells in vitro, as judged by the micronucleus assay

    Mutagenesis

    (1993)
  • H Schilling et al.

    Long-term results after low dose ocular irradiation for choroidal haemangiomas

    Br J Ophthalmol

    (1997)
  • J Archambeau et al.

    What is the role of radiation in the treatment of subfoveal membranesreview of radiobiologic, pathologic, and other considerations to initiate a multimodality discussion

    Int J Radiat Oncol Biol Phys

    (1988)
  • U Chakravarthy et al.

    Treatment of age-related subfoveal neovascular membranes by teletherapya pilot study

    Br J Ophthalmol

    (1993)
  • Cited by (51)

    • Radiation therapy for neovascular age-related macular degeneration

      2013, International Journal of Radiation Oncology Biology Physics
      Citation Excerpt :

      These promising results led to 11 phase 3, randomized controlled trials (Table 2) (51-61). Several studies found statistically significant benefits in patients treated with EBRT (52, 53, 55, 56, 61), whereas others found no lasting benefit (51, 54, 57-60). Notably, some studies found significant improvements only for VA and not in terms of CNV membrane size (52, 53, 61), whereas others did not find improvements in VA overall but did find significant benefits in classic CNV regression or contrast sensitivity preservation (59, 60).

    View all citing articles on Scopus
    View full text