Detailed optical coherence tomography angiographic short-term response of type 3 neovascularization to combined treatment with photodynamic therapy and intravitreal bevacizumab

Abstract

Purpose: To explore the short-term vascular and structural changes of type 3 neovascularization using optical coherence tomography angiography (OCT-A) when treated with a combination of photodynamic therapy (PDT) and intravitreal bevacizumab (IVB), and to evaluate the course of different sequences of the combined therapies.

Methods: Thirty eyes of 29 treatment-naïve patients with a type 3 neovascularization were included in this prospective observational cohort study. They were all treated with PDT and IVB 2 weeks apart, starting either with PDT (PDT-first group) or IVB (IVB-first group). Optical coherence tomography angiography (OCT-A) imaging was performed at week 0, 2, 4 and 18, and best corrected visual acuity (BCVA) at week 0 and 18. Vascular, structural and functional features were graded and analysed over time.

Results: In all patients, at all follow-up visits, vascular and structural features were significantly more often decreased or resolved than unchanged or increased. Best corrected visual acuity (BCVA) significantly improved at 18 weeks. Vascular, structural and functional outcomes were all slightly better in the PDT-first group compared to the IVB-first group, although not statistically significant.

Conclusion: Combined treatment of PDT and IVB is effective in short-term for type 3 neovascularization based on vascular and structural features. Initial treatment with PDT tended to be more effective than with IVB.

Keywords: anti-VEGF; intraretinal cysts; intraretinal neovascularization; intravitreal bevacizumab; optical coherence tomography angiography; photodynamic therapy; retinal choroidal anastomosis; type 3 neovascularization.