Purchase this article with an account.
Andreas Karydis, Emily Han Shao, Maria K Gemenetzi, Simon Richard Taylor; Intravitreal Bevacizumab vs. Dexamethasone implant in Retinal Vein Occlusion: a Crossover Study.. Invest. Ophthalmol. Vis. Sci. 2014;55(13):3911.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Branch and central retinal vein occlusions (RVO) are frequent causes of permanent visual loss for which several intravitreal treatment options have now been developed. However, head-to-head trials between these agents are limited. Local health commissioning changed the available treatment for RVO from bevacizumab to dexamethasone implant in 2011. We used this to perform a retrospective crossover study comparing the response to treatment of both bevacizumab and dexamethasone implant in patients with RVO including visual outcomes and improvements in central macular thickness (CMT).
Nine patients with a diagnosis of RVO who received both intravitreal bevacizumab and dexamethasone implant were retrospectively identified from the clinic database. Visual acuity (EDTRS letters) and Central Macular Thickness (CMT; μm) at baseline prior to treatment and three months after each intervention were recorded. 3 months was chosen as this represents the peak effect of both the dexamethasone implant and 3 loading doses of bevacizumab. Statistical analysis comparing the mean change in visual acuity and CMT between the two interventions was conducted using the paired sample t-test (SPSS version 20).
Intravitreal bevacizumab resulted in an average improvement in distance visual acuity of 18 EDTRS letters, compared to only 2 letters 3 months post intravitreal dexamethasone implant (95% CI = 3.1 - 29.5; p = 0.021), even though the starting visual acuities were similar (52.1 vs 58.6 letters; p = 0.24) (figure 1). Conversely, however, intravitreal dexamethasome resulted in a greater mean reduction in CMT than intravitreal bevacizumab (mean reduction 136 μm vs. 95 μm) although this difference did not reach statistical significance (95% CI= -89.5 - 125.5 μm; p = 0.69) (figure 2).
In this crossover study, intravitreal bevacizumab resulted in significantly greater improvement in visual function in the management of retinal vein occlusion with subsequent cystoid macular oedema at 3 months when compared to intravitreal dexamethasone implant, even though the dexamethasone implant achieved a greater mean reduction in central macular thickness at this timepoint. This suggests that macular thickness is not the only determinant of visual acuity in these patients, but that other factors affected by anti-VEGF therapy such as retinal non-perfusion may also be of importance.
This PDF is available to Subscribers Only