Response to anti-vascular endothelial growth factor of abnormal retinal vascular net in para foveal telangiectasia group II images on optical coherence tomography-angiography.

Purpose: To identify optical coherence tomography-angiography (OCT-A) findings to predict treatment response during anti-vascular endothelial growth factor (VEGF) therapy in eyes with para foveal telangiectasia (PFT) group II.

Methods: In this retrospective series, Twelve eyes of seven patients diagnosed with PFT group II without evidence of sub-retinal neovascular membrane (SRNVM) clinically or on spectral domain-OCT (SD-OCT) were included. All patients underwent OCT-A on the Topcon DRI OCT Triton with 4.5 mm macula scans. The patients with abnormal vascular nets were further classified into type A and B nets and administered intravitreal anti-VEGF therapy. Visual acuity and size of type A and B nets were evaluated pre- and post-injection. Paired t- test and intraclass correlation were used to analyse data.

Results: Patients with type A net showed significant improvement in visual acuity (logMAR 0.38, P = 0.0047). The size of type A net showed statistically significant decrease (P = 0.0008) on 6 month follow up. Type B net did not show statistically significant difference in visual acuity or size following anti-VEGF therapy.

Conclusion: OCT-A plays an important role in early detection of possible neovascular nets (type A), in the absence of obvious SRNVM. Treatment decisions based on OCT-A may be helpful to achieve better visual outcome.