Work

Significant Correlation Between Choroidal Thickness and Decrease in Choroidal Blood Flow After Switching to Brolucizumab for Refractory Neovascular Age-Related Macular Degeneration

Year: 2025

Type: article

Abstract: Anti-vascular endothelial growth factor (VEGF) therapy suppresses neovascularization in neovascular age-related macular degeneration (nAMD) but may reduce ocular blood flow. However, its relationship with choroidal thickness remains unclear. This study evaluated 1-month outcomes after switching from intravitreal aflibercept or ranibizumab to intravitreal brolucizumab (IVBr) in patients with refractory nAMD. This prospective, single-center study included 50 eyes of 50 patients with nAMD. Changes in best-corrected visual acuity (BCVA), central retinal thickness (CRT), subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI), choroidal stromal area (SA), choroidal luminal area (LA), optic nerve head (ONH) mean blur rate (MBR), and choroidal (CHOR) MBR were evaluated before and 1 month after switching to IVBr, with blood flow measured using laser speckle flowgraphy. Univariate analyses were performed to identify potential predictors of changes in CHOR-MBR, and variables with P < 0.1 were entered into a multiple regression model. BCVA was maintained. CRT decreased from 371.6 ± 118.7 to 288.8 ± 89.7 µm (P < 0.001). SFCT decreased from 231.9 ± 118.7 to 196.0 ± 117.4 µm (P < 0.001). CVI showed no significant changes, while SA and LA exhibited significant reductions. ONH-MBR and CHOR-MBR decreased (P = 0.004 and P < 0.001, respectively). The baseline SFCT was the only significant predictor of change in CHOR-MBR. Older age correlated with thinner baseline SFCT and a greater decrease in CHOR-MBR. IVBr is associated with significant reductions in CRT and SFCT and may decrease choroidal blood flow, particularly in older patients and those with thinner SFCTs. UMIN-CTR Registration ID, UMIN000041382. Neovascular age-related macular degeneration (nAMD) is a common cause of vision loss in older adults. It is treated with anti-vascular endothelial growth factor (anti-VEGF) injections to reduce abnormal blood vessel growth and retinal swelling. However, anti-VEGF drugs may also reduce blood flow in the eye, which could be harmful in some patients. This study included 50 patients with nAMD whose disease was not fully controlled by standard anti-VEGF treatments (aflibercept or ranibizumab). All patients were switched to a newer anti-VEGF drug called brolucizumab and were examined before and 1 month after the switch. We measured vision, retinal thickness, choroidal thickness (a layer of blood vessels under the retina), and blood flow using a noninvasive imaging method called laser speckle flowgraphy. One month after switching, retinal swelling and choroidal thickness were reduced, but blood flow in the choroid also decreased, especially in older patients and those with thinner choroids before treatment. These findings suggest that measuring choroidal thickness and blood flow before starting brolucizumab may help identify patients who are more likely to experience reduced eye blood flow. This could help doctors tailor treatment plans to reduce potential risks while still controlling the disease.

Source: Ophthalmology and Therapy

DOI: 10.1007/s40123-025-01279-9