FDA's role in expediting innovation of bioelectronic implants for vision restoration.

Bioelectronic implants for vision restoration are medical devices regulated in the United States by the Food and Drug Administration (FDA). This paper provides an overview of regulatory pathways and related FDA programs for bioelectronic implants for vision restoration, and identifies some of the gaps in the regulatory science of these devices. The FDA recognizes that additional discussion regarding development in this space is needed to further develop bioelectronic implants and ensure that safe and effective technologies are made available to patients with profound vision loss. FDA regularly participates in the Eye and the Chip World Research Congress meetings and continues to engage with important external stakeholders, including through public workshops such as the recent co-sponsored Expediting Innovation of Bioelectronic Implants for Vision Restoration. By participating in forums for discussion of these devices with all stakeholders, especially patients, FDA seeks to encourage advancement of these devices.

Inflammatory response to intravitreal injection of gold nanorods.

AIM: To evaluate the utility of gold nanorods (AuNRs) as a contrast agent for ocular optical coherence tomography (OCT). METHODS: Mice were intravitreally injected with sterile AuNRs coated with either poly(strenesulfate) (PSS-AuNRs) or anti-CD90.2 antibodies (Ab-AuNRs), and imaged using OCT. After 24 h, eyes were processed for transmission electron microscopy or rendered into single cell suspensions for flow cytometric analysis to determine absolute numbers of CD45(+) leukocytes and subsets (T cells, myeloid cells, macrophages, neutrophils). Generalised estimation equations were used to compare cell counts between groups. RESULTS: PSS-AuNRs and Ab-AuNRs were visualised in the vitreous 30 min and 24 h post-injection with OCT. At 24 h, a statistically significant increase in leukocytes, comprised primarily of neutrophils, was observed in eyes that received either AuNR in comparison to eyes that received saline. The accumulation of leukocytes was equal in eyes given PSS-AuNR or Ab-AuNR. Endotoxin-resistant C3H/HeJ mice also showed ocular inflammation after injection with AuNRs, indicating that the inflammatory response was not due to lipopolysaccharide contamination of AuNRs. CONCLUSIONS: Although AuNRs can be visualised in the eye using OCT, they can induce ocular inflammation, which limits their use as a contrast agent.