Dexamethasone implant improves anatomic response to anti-VEGF therapy in treatment-resistant Polypoidal Choroidal Vasculopathy

Abstract

Background: A significant proportion of eyes with polypoidal choroidal vasculopathy (PCV) can be resistant to anti-vascular endothelial growth factor (VEGF) injections. We evaluated the efficacy of combination of Dexamethasone intravitreal implant (DXI) and anti-VEGF therapy in eyes resistant to anti-VEGF monotherapy.Materials and Methods: In this retrospective study, polypoidal choroidal vasculopathy (PCV) resistant to anti-VEGF injections were additionally injected with a Dexamethasone implant along with an anti-VEGF agent. Best-corrected visual acuity (BCVA), slit lamp examination, intraocular pressure, fundus evaluation and optical coherence tomography (OCT) data were analyzed. Anatomical response on OCT was the primary outcome measure. Gain in visual acuity, and injection-free interval after the Dexamethasone implant were evaluated as secondary outcome measures.Results: Twelve eyes of 11 patients were included in the study. The mean age of patients was 70.2 ± 11.8 years, and there were 8 females. The mean follow-up duration after DXI was 24.5 ±11 months. The mean number of anti-VEGF injections before DXI was 4.2 ± 1.9. The mean injection-free interval in these patients after DXI was 4.7± 0.6 months, which was significantly greater than the pre-injection mean of 1.6 ± 0.4 months (p<0.001). The median log MAR BCVA immediately prior to DXI was 0.41 (Interquartile Range IQR 0.30-1.02) and after injection was 0.60 (IQR 0.27-1.03), which was not significant (p=0.59). The median OCT thickness after DXI in was 305 microns (IQR 206-417), which was significantly less than the pre-injection OCT thickness of 547 microns (IQR 432-685) (p=0.005). The mean IOP before DXI was 14.7 ± 2.3 mm Hg, and after the injection was 14.3 ± 2.7 mm Hg (p=0.36). Conclusions: Dexamethasone implant combined with anti-VEGF treatment can prolong the treatment-free interval in eyes with PCV resistant to anti-VEGF injection, while maintaining visual acuity.