Low-energy Stereotactic Radiotherapy for Treatment of Exudative Age-related Macular Degeneration Adjunctive to Anti-VEGF Therapy

Abstract

The number of cases of patients with exudative age-related macular degeneration (wet AMD) is increasing, partly due to an ageing population and lifestyle risk factors, such as smoking. The treatment of wet AMD has been revolutionised by the advent of anti-vascular endothelial growth factor (anti-VEGF) agents, though it is an important aim to reduce the treatment burden for patients with the need for highly frequent treatment. Previously, combinations of anti-VEGF with Verteporfin PhotoDynamic Therapy and radiation therapy were used to achieve this aim. More recently, stereotactic radiotherapy (SRT) has been shown in the IRay Plus Anti-VEGF Treatment For Patients With Wet AMD (INTREPID) study to preserve vision while sparing injections of anti-VEGF. Using a highly collimated, narrow X-ray beam, the dose of radiation is delivered in three closely spaced applications within a single session through different entry points in the inferior pars plana of the affected eye. The total application time is usually less than 60 minutes. Centred on the fovea, the sequential beams converge on the retina to deliver a 16 Gy dose to an area of 4 mm in diameter. In this opinion-based article, the practical application of SRT adjunctive to anti-VEGF therapy is discussed and illustrated with a series of case studies. KeywordsStereotactic radiotherapy (SRT),radiosurgery (SRS), radiotherapy, ionising radiation, neovascular age-related macular degeneration (wet AMD), anti-vascular endothelial growth factor (anti-VEGF) Disclosure: Katja Hatz has received fees for lectures and congress travel expenses from Alcon, Allergan, Bayer Switzerland, Novartis, Oraya and Roche and advisory board fees from