Vascular regeneration and blood flow recovery in glaucoma

The retina and optic nerve rely on a tightly regulated neurovascular unit that sustains the highly dynamic and metabolically demanding neural tissues required for vision. Adequate oxygen and nutrient delivery are essential for maintaining tissue function and cellular survival. Over the past decades, extensive research within and beyond the field of ophthalmology has sought to elucidate the mechanisms that govern neurovascular regulation in health and disease. Growing evidence indicates that neurovascular dysfunction plays an important role in both the initiation and progression of glaucoma, a leading cause of irreversible blindness worldwide. Alterations in vascular architecture and blood flow may compromise the metabolic support required by retinal ganglion cells, increasing their vulnerability to injury and degeneration. While neurons possess limited regenerative capacity, the vascular system retains a remarkable degree of plasticity and is therefore amenable to repair. This vascular plasticity presents an opportunity to develop therapeutic strategies aimed at restoring vascular architecture and improving blood flow, complementing existing approaches focused on intraocular pressure reduction, neuroprotection, axonal regeneration, and/or neuronal transplantation. In this review, we summarize the current understanding of neurovascular function in the healthy eye, discuss mechanisms that contribute to vascular compromise in glaucoma, and highlight emerging avenues for promoting vascular regeneration and blood flow recovery. By identifying key knowledge gaps and future research priorities, we aim to outline promising directions for targeting the ocular neurovasculature to preserve retinal ganglion cell function and slow or stop progressive vision loss.