Modalities of vision restoration in optic neuropathies and retinal disease

Visual impairment affects over 250 million people globally and carries a significant psychosocial and economic burden. In recent years, rapid advancements in biomedical engineering and regenerative medicine have driven the development of innovative therapies aimed at restoring visual function. Here, we first provide an overview of the visual pathway, imaging modalities, and the psychosocial and economic burden of vision loss. Then we review four vision restoration approaches: gene and stem cell therapies, optogenetics, retinal prosthetic devices, and visual pathway electrical stimulation. For each therapeutic approach, the mechanism of action, clinical outcomes, adverse events, and current limitations are discussed. Stem cell transplantation and gene-editing technologies are being explored to repair or replace damaged retinal cells at the molecular level. Retinal prosthetics implanted in various layers of the retina induce visual experiences in patients with degenerative diseases, though challenges in resolution and long-term performance remain. Lastly, electrical stimulation techniques, including transcorneal and transorbital stimulation, have shown potential to enhance residual vision through neuroprotective measures and neuroplastic synchronization of neuronal signaling activity. This article reviews and compares these therapies to give a balanced perspective on treatment modalities for visual impairment in a range of retinal diseases and optic neuropathies.