ANTI-VEGF

The inhibition of vascular endothelial growth factor provides a substantial long-term benefit in patients with macular oedema secondary to branch retinal vein occlusion, Sandra Rezar MD told delegates attending the 2013 Congress of the Society of European Ophthalmology (SOE). “Our study with a mean follow-up of five years found good long-term functional and anatomical outcomes using anti-VEGF treatment in patients with branch retinal vein occlusion, with an average gain of 15 letters of visual acuity, significantly reduced retinal thickness and improved retinal sensitivity,” she reported.

She added that early intervention and rigorous follow-up with anti-VEGF agents such as bevacizumab or ranibizumab are important to ensure optimal patient outcomes, and advised using 200-degree wide-field angiography for the evaluation of the peripheral retina. Dr Rezar, Medical University of Vienna, Austria, said that retinal vein occlusion (RVO) is a sight-threatening retinal vascular disorder associated with macular oedema and neovascularisation that affects an estimated 16.4 million people worldwide. Branch retinal vein occlusion is the most common type (13.9 million) compared to central retinal vein occlusion (2.5 million).

While the exact pathogenesis of the occlusion is not well understood, various local and systemic factors appear to play a role in the pathological closure of the retinal veins. Patients with retinal vein occlusion can additionally suffer from cardiovascular disease or stroke, said Dr Rezar. In the event of macular oedema occurring secondary to the RVO, the standard treatment is now to use anti- VEGF injections or corticosteroids such as dexamethasone or triamcinolone.

“While a number of studies have demonstrated the short-term safety and efficacy of anti-VEGF treatments for RVO, there really is not a lot of data available concerning the long-term outcome of these patients,” said Dr Rezar. The study conducted by the Macula Study Group of Vienna evaluated an initial cohort of 54 patients treated for macula oedema secondary to branch retinal vein occlusion. Twenty-five patients received intravitreal ranibizumab injections and the remaining 29 patients were treated with bevacizumab. After a mean follow-up of five years, 28 of the patients were included in the crosssectional study. Main outcome measures included mean change in best-corrected visual acuity (BCVA) from baseline, change in central retinal thickness (CRT) and retinal sensitivity (CRS). Follow-up at a mean of six years was slightly longer for the bevacizumab patients compared to four years for those treated with ranibizumab.

Mean time

The mean time between onset of RVO and initial treatment was 188 days (±141) for the 14 patients in the bevacizumab treated group and 51 days (±31) for the other 14 patients in the ranibizumab group. Patients received an average of nine intravitreal injections for bevacizumab and six for ranibizumab, while another 10 patients received segmental laser coagulation.

Dr Rezar noted that the frequency of injections diminished significantly over time, from an average of 3.82 per patient in the first six months of treatment, to 0.25 in months 37 to 42. In the bevacizumab group, the average visual acuity increased by six letters, which was not, however, statistically significant, CRS improved by 3.1dB and CRT thickness decreased by 162 μm. In the ranibizumab group, visual acuity and CRS also increased significantly (27 letters and 4.6dB) and the CRT decreased 229μm.