Abstract
Purpose :
Although anti-VEGF treatment results in improvements in retinal morphology and visual acuity, fibrosis occurs over time in the neovascular lesion and has recently been implicated in failure to effectively preserve visual acuity.To better understand evolution of fibrosis during anti-VEGF treatment, we explored its relationships with CNV subtype, the presence, severity and location of hyperreflective material (HRM) and tear of the retinal pigment epithelium by conducting a revised grading of the image repository in the IVAN trial.
Methods :
In the subset of the IVAN trial (n = 135) participants who had spectral domain optical coherence tomography (SD-OCT) performed, we systematically classified the neovascular AMD lesion using both OCT modality and fluorescein angiographic features into specific nAMD subtypes. These were type 1 (occult), type 2 (classic), type 3 (retinal angiomatous proliferation), type 4 (polypoidal choroidal vasculopathy, PCV). Based on the SD-OCT we sub-classified HRM as subretinal non-fibrotic and fibrotic, subRPE non-fibrotic and fibrotic using both location and reflectivity to assign these characteristics. We measured the area of fibrosis on FA and height and width of the HRM on OCT.
Results :
All patients had color fundus photograph (CFP), fluorescein angiography(FA)and SD-OCT at baseline and final visit at 24 months (M24). Among 135 eyes, the proportions of type 1, type 2, type 3 and type 4 CNV were 28.1% (n=38), 25.9% (n=35), 22.2% (n=30), and 23.0% (n=31), respectively. At baseline and M24, the mean height of HRM on OCT was 107.19± 104.15μm and 73.63±89.78μm. The mean width of HRM was 770.12 ± 845.26μm and 516.64± 686.86μm, respectively. The height and width of HRM were strongly correlated at baseline as well at final visit (Pearson’s r=0.837 and Pearson’s r=0.865, respectively), and the height and width of HRM were significant decreased at final visit 24 month compared to baseline (p=0.007 and p=0.010, respectively). The type 1 and type 4 CNV showed significant reduction in both height and width of HRM, however in type 2 and type 3, there was no reduction of HRM in either height or width.
Conclusions :
In eyes with nAMD undergoing two years’ anti-VEGF treatment and follow up, the reduction of height and width of HRM was observed in various CNV subtypes, except type 2 and type 3.
This is a 2020 ARVO Annual Meeting abstract.