Quantitative analysis of branching neovascular networks in polypoidal choroidal vasculopathy by optical coherence tomography angiography after photodynamic therapy and anti-vascular endothelial growth factor combination therapy.

PURPOSE

To study serial changes in branching neovascular networks (BNN) by using optical coherence tomography angiography (OCTA) in patients with polypoidal choroidal vasculopathy (PCV) who underwent combined photodynamic therapy (PDT) and anti-vascular endothelial growth factor (anti-VEGF) therapy.

METHODS

In this retrospective study of 30 PCV patients who underwent combined therapy, OCTA images obtained at baseline and 1, 3, and 6 months after treatment were collected. The vessel area, vessel percentage area, average vessel length, and presence of polypoidal lesions on OCTA images as well as best-corrected visual acuity (BCVA), central retinal thickness (CRT), and central choroidal thickness (CCT) were recorded at each time point.

RESULTS

The BNN- and polypoidal lesion-detection rates on baseline OCTA images were 100% and 71%, respectively. The vessel area decreased during the first 3 months, and increased 6 months post-treatment, showing significant differences from baseline (p = 0.031). The vessel percentage area also reduced 1 and 3 months post-treatment (p = 0.025) and increased 6 months post-treatment. Continuous polypoidal lesion regression was observed from 1 to 3 and 6 months post-treatment (p = 0.031, p = 0.004, p = 0.002, respectively, in comparison with baseline). Patients with a decreasing vessel area over 6 months showed greater choroidal thickness than those with increasing vessel area (p = 0.004).

CONCLUSIONS

The BNN showed initial regression but were enlarged at 6 months after therapy. Patients showing continuous BNN regression showed a thicker choroid at baseline. This difference should be considered during treatment for PCV, and OCTA could be used for follow-up evaluations of PCV patients.